// Go support for Protocol Buffers - Google's data interchange format
//
// Copyright 2010 The Go Authors. All rights reserved.
// https://github.com/golang/protobuf
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
/*
The code generator for the plugin for the Google protocol buffer compiler.
It generates Go code from the protocol buffer description files read by the
main routine.
*/
package generator
import (
"bufio"
"bytes"
"compress/gzip"
"crypto/sha256"
"encoding/hex"
"fmt"
"go/ast"
"go/build"
"go/parser"
"go/printer"
"go/token"
"log"
"os"
"path"
"sort"
"strconv"
"strings"
"unicode"
"unicode/utf8"
"github.com/golang/protobuf/proto"
"github.com/golang/protobuf/protoc-gen-go/generator/internal/remap"
"github.com/golang/protobuf/protoc-gen-go/descriptor"
plugin "github.com/golang/protobuf/protoc-gen-go/plugin"
)
// generatedCodeVersion indicates a version of the generated code.
// It is incremented whenever an incompatibility between the generated code and
// proto package is introduced; the generated code references
// a constant, proto.ProtoPackageIsVersionN (where N is generatedCodeVersion).
const generatedCodeVersion = 3
// A Plugin provides functionality to add to the output during Go code generation,
// such as to produce RPC stubs.
type Plugin interface {
// Name identifies the plugin.
Name() string
// Init is called once after data structures are built but before
// code generation begins.
Init(g *Generator)
// Generate produces the code generated by the plugin for this file,
// except for the imports, by calling the generator's methods P, In, and Out.
Generate(file *FileDescriptor)
// GenerateImports produces the import declarations for this file.
// It is called after Generate.
GenerateImports(file *FileDescriptor)
}
var plugins []Plugin
// RegisterPlugin installs a (second-order) plugin to be run when the Go output is generated.
// It is typically called during initialization.
func RegisterPlugin(p Plugin) {
plugins = append(plugins, p)
}
// A GoImportPath is the import path of a Go package. e.g., "google.golang.org/genproto/protobuf".
type GoImportPath string
func (p GoImportPath) String() string { return strconv.Quote(string(p)) }
// A GoPackageName is the name of a Go package. e.g., "protobuf".
type GoPackageName string
// Each type we import as a protocol buffer (other than FileDescriptorProto) needs
// a pointer to the FileDescriptorProto that represents it. These types achieve that
// wrapping by placing each Proto inside a struct with the pointer to its File. The
// structs have the same names as their contents, with "Proto" removed.
// FileDescriptor is used to store the things that it points to.
// The file and package name method are common to messages and enums.
type common struct {
file *FileDescriptor // File this object comes from.
}
// GoImportPath is the import path of the Go package containing the type.
func (c *common) GoImportPath() GoImportPath {
return c.file.importPath
}
func (c *common) File() *FileDescriptor { return c.file }
func fileIsProto3(file *descriptor.FileDescriptorProto) bool {
return file.GetSyntax() == "proto3"
}
func (c *common) proto3() bool { return fileIsProto3(c.file.FileDescriptorProto) }
// Descriptor represents a protocol buffer message.
type Descriptor struct {
common
*descriptor.DescriptorProto
parent *Descriptor // The containing message, if any.
nested []*Descriptor // Inner messages, if any.
enums []*EnumDescriptor // Inner enums, if any.
ext []*ExtensionDescriptor // Extensions, if any.
typename []string // Cached typename vector.
index int // The index into the container, whether the file or another message.
path string // The SourceCodeInfo path as comma-separated integers.
group bool
}
// TypeName returns the elements of the dotted type name.
// The package name is not part of this name.
func (d *Descriptor) TypeName() []string {
if d.typename != nil {
return d.typename
}
n := 0
for parent := d; parent != nil; parent = parent.parent {
n++
}
s := make([]string, n)
for parent := d; parent != nil; parent = parent.parent {
n--
s[n] = parent.GetName()
}
d.typename = s
return s
}
// EnumDescriptor describes an enum. If it's at top level, its parent will be nil.
// Otherwise it will be the descriptor of the message in which it is defined.
type EnumDescriptor struct {
common
*descriptor.EnumDescriptorProto
parent *Descriptor // The containing message, if any.
typename []string // Cached typename vector.
index int // The index into the container, whether the file or a message.
path string // The SourceCodeInfo path as comma-separated integers.
}
// TypeName returns the elements of the dotted type name.
// The package name is not part of this name.
func (e *EnumDescriptor) TypeName() (s []string) {
if e.typename != nil {
return e.typename
}
name := e.GetName()
if e.parent == nil {
s = make([]string, 1)
} else {
pname := e.parent.TypeName()
s = make([]string, len(pname)+1)
copy(s, pname)
}
s[len(s)-1] = name
e.typename = s
return s
}
// Everything but the last element of the full type name, CamelCased.
// The values of type Foo.Bar are call Foo_value1... not Foo_Bar_value1... .
func (e *EnumDescriptor) prefix() string {
if e.parent == nil {
// If the enum is not part of a message, the prefix is just the type name.
return CamelCase(*e.Name) + "_"
}
typeName := e.TypeName()
return CamelCaseSlice(typeName[0:len(typeName)-1]) + "_"
}
// The integer value of the named constant in this enumerated type.
func (e *EnumDescriptor) integerValueAsString(name string) string {
for _, c := range e.Value {
if c.GetName() == name {
return fmt.Sprint(c.GetNumber())
}
}
log.Fatal("cannot find value for enum constant")
return ""
}
// ExtensionDescriptor describes an extension. If it's at top level, its parent will be nil.
// Otherwise it will be the descriptor of the message in which it is defined.
type ExtensionDescriptor struct {
common
*descriptor.FieldDescriptorProto
parent *Descriptor // The containing message, if any.
}
// TypeName returns the elements of the dotted type name.
// The package name is not part of this name.
func (e *ExtensionDescriptor) TypeName() (s []string) {
name := e.GetName()
if e.parent == nil {
// top-level extension
s = make([]string, 1)
} else {
pname := e.parent.TypeName()
s = make([]string, len(pname)+1)
copy(s, pname)
}
s[len(s)-1] = name
return s
}
// DescName returns the variable name used for the generated descriptor.
func (e *ExtensionDescriptor) DescName() string {
// The full type name.
typeName := e.TypeName()
// Each scope of the extension is individually CamelCased, and all are joined with "_" with an "E_" prefix.
for i, s := range typeName {
typeName[i] = CamelCase(s)
}
return "E_" + strings.Join(typeName, "_")
}
// ImportedDescriptor describes a type that has been publicly imported from another file.
type ImportedDescriptor struct {
common
o Object
}
func (id *ImportedDescriptor) TypeName() []string { return id.o.TypeName() }
// FileDescriptor describes an protocol buffer descriptor file (.proto).
// It includes slices of all the messages and enums defined within it.
// Those slices are constructed by WrapTypes.
type FileDescriptor struct {
*descriptor.FileDescriptorProto
desc []*Descriptor // All the messages defined in this file.
enum []*EnumDescriptor // All the enums defined in this file.
ext []*ExtensionDescriptor // All the top-level extensions defined in this file.
imp []*ImportedDescriptor // All types defined in files publicly imported by this file.
// Comments, stored as a map of path (comma-separated integers) to the comment.
comments map[string]*descriptor.SourceCodeInfo_Location
// The full list of symbols that are exported,
// as a map from the exported object to its symbols.
// This is used for supporting public imports.
exported map[Object][]symbol
importPath GoImportPath // Import path of this file's package.
packageName GoPackageName // Name of this file's Go package.
proto3 bool // whether to generate proto3 code for this file
}
// VarName is the variable name we'll use in the generated code to refer
// to the compressed bytes of this descriptor. It is not exported, so
// it is only valid inside the generated package.
func (d *FileDescriptor) VarName() string {
h := sha256.Sum256([]byte(d.GetName()))
return fmt.Sprintf("fileDescriptor_%s", hex.EncodeToString(h[:8]))
}
// goPackageOption interprets the file's go_package option.
// If there is no go_package, it returns ("", "", false).
// If there's a simple name, it returns ("", pkg, true).
// If the option implies an import path, it returns (impPath, pkg, true).
func (d *FileDescriptor) goPackageOption() (impPath GoImportPath, pkg GoPackageName, ok bool) {
opt := d.GetOptions().GetGoPackage()
if opt == "" {
return "", "", false
}
// A semicolon-delimited suffix delimits the import path and package name.
sc := strings.Index(opt, ";")
if sc >= 0 {
return GoImportPath(opt[:sc]), cleanPackageName(opt[sc+1:]), true
}
// The presence of a slash implies there's an import path.
slash := strings.LastIndex(opt, "/")
if slash >= 0 {
return GoImportPath(opt), cleanPackageName(opt[slash+1:]), true
}
return "", cleanPackageName(opt), true
}
// goFileName returns the output name for the generated Go file.
func (d *FileDescriptor) goFileName(pathType pathType) string {
name := *d.Name
if ext := path.Ext(name); ext == ".proto" || ext == ".protodevel" {
name = name[:len(name)-len(ext)]
}
name += ".pb.go"
if pathType == pathTypeSourceRelative {
return name
}
// Does the file have a "go_package" option?
// If it does, it may override the filename.
if impPath, _, ok := d.goPackageOption(); ok && impPath != "" {
// Replace the existing dirname with the declared import path.
_, name = path.Split(name)
name = path.Join(string(impPath), name)
return name
}
return name
}
func (d *FileDescriptor) addExport(obj Object, sym symbol) {
d.exported[obj] = append(d.exported[obj], sym)
}
// symbol is an interface representing an exported Go symbol.
type symbol interface {
// GenerateAlias should generate an appropriate alias
// for the symbol from the named package.
GenerateAlias(g *Generator, filename string, pkg GoPackageName)
}
type messageSymbol struct {
sym string
hasExtensions, isMessageSet bool
oneofTypes []string
}
type getterSymbol struct {
name string
typ string
typeName string // canonical name in proto world; empty for proto.Message and similar
genType bool // whether typ contains a generated type (message/group/enum)
}
func (ms *messageSymbol) GenerateAlias(g *Generator, filename string, pkg GoPackageName) {
g.P("// ", ms.sym, " from public import ", filename)
g.P("type ", ms.sym, " = ", pkg, ".", ms.sym)
for _, name := range ms.oneofTypes {
g.P("type ", name, " = ", pkg, ".", name)
}
}
type enumSymbol struct {
name string
proto3 bool // Whether this came from a proto3 file.
}
func (es enumSymbol) GenerateAlias(g *Generator, filename string, pkg GoPackageName) {
s := es.name
g.P("// ", s, " from public import ", filename)
g.P("type ", s, " = ", pkg, ".", s)
g.P("var ", s, "_name = ", pkg, ".", s, "_name")
g.P("var ", s, "_value = ", pkg, ".", s, "_value")
}
type constOrVarSymbol struct {
sym string
typ string // either "const" or "var"
cast string // if non-empty, a type cast is required (used for enums)
}
func (cs constOrVarSymbol) GenerateAlias(g *Generator, filename string, pkg GoPackageName) {
v := string(pkg) + "." + cs.sym
if cs.cast != "" {
v = cs.cast + "(" + v + ")"
}
g.P(cs.typ, " ", cs.sym, " = ", v)
}
// Object is an interface abstracting the abilities shared by enums, messages, extensions and imported objects.
type Object interface {
GoImportPath() GoImportPath
TypeName() []string
File() *FileDescriptor
}
// Generator is the type whose methods generate the output, stored in the associated response structure.
type Generator struct {
*bytes.Buffer
Request *plugin.CodeGeneratorRequest // The input.
Response *plugin.CodeGeneratorResponse // The output.
Param map[string]string // Command-line parameters.
PackageImportPath string // Go import path of the package we're generating code for
ImportPrefix string // String to prefix to imported package file names.
ImportMap map[string]string // Mapping from .proto file name to import path
Pkg map[string]string // The names under which we import support packages
outputImportPath GoImportPath // Package we're generating code for.
allFiles []*FileDescriptor // All files in the tree
allFilesByName map[string]*FileDescriptor // All files by filename.
genFiles []*FileDescriptor // Those files we will generate output for.
file *FileDescriptor // The file we are compiling now.
packageNames map[GoImportPath]GoPackageName // Imported package names in the current file.
usedPackages map[GoImportPath]bool // Packages used in current file.
usedPackageNames map[GoPackageName]bool // Package names used in the current file.
addedImports map[GoImportPath]bool // Additional imports to emit.
typeNameToObject map[string]Object // Key is a fully-qualified name in input syntax.
init []string // Lines to emit in the init function.
indent string
pathType pathType // How to generate output filenames.
writeOutput bool
annotateCode bool // whether to store annotations
annotations []*descriptor.GeneratedCodeInfo_Annotation // annotations to store
}
type pathType int
const (
pathTypeImport pathType = iota
pathTypeSourceRelative
)
// New creates a new generator and allocates the request and response protobufs.
func New() *Generator {
g := new(Generator)
g.Buffer = new(bytes.Buffer)
g.Request = new(plugin.CodeGeneratorRequest)
g.Response = new(plugin.CodeGeneratorResponse)
return g
}
// Error reports a problem, including an error, and exits the program.
func (g *Generator) Error(err error, msgs ...string) {
s := strings.Join(msgs, " ") + ":" + err.Error()
log.Print("protoc-gen-go: error:", s)
os.Exit(1)
}
// Fail reports a problem and exits the program.
func (g *Generator) Fail(msgs ...string) {
s := strings.Join(msgs, " ")
log.Print("protoc-gen-go: error:", s)
os.Exit(1)
}
// CommandLineParameters breaks the comma-separated list of key=value pairs
// in the parameter (a member of the request protobuf) into a key/value map.
// It then sets file name mappings defined by those entries.
func (g *Generator) CommandLineParameters(parameter string) {
g.Param = make(map[string]string)
for _, p := range strings.Split(parameter, ",") {
if i := strings.Index(p, "="); i < 0 {
g.Param[p] = ""
} else {
g.Param[p[0:i]] = p[i+1:]
}
}
g.ImportMap = make(map[string]string)
pluginList := "none" // Default list of plugin names to enable (empty means all).
for k, v := range g.Param {
switch k {
case "import_prefix":
g.ImportPrefix = v
case "import_path":
g.PackageImportPath = v
case "paths":
switch v {
case "import":
g.pathType = pathTypeImport
case "source_relative":
g.pathType = pathTypeSourceRelative
default:
g.Fail(fmt.Sprintf(`Unknown path type %q: want "import" or "source_relative".`, v))
}
case "plugins":
pluginList = v
case "annotate_code":
if v == "true" {
g.annotateCode = true
}
default:
if len(k) > 0 && k[0] == 'M' {
g.ImportMap[k[1:]] = v
}
}
}
if pluginList != "" {
// Amend the set of plugins.
enabled := make(map[string]bool)
for _, name := range strings.Split(pluginList, "+") {
enabled[name] = true
}
var nplugins []Plugin
for _, p := range plugins {
if enabled[p.Name()] {
nplugins = append(nplugins, p)
}
}
plugins = nplugins
}
}
// DefaultPackageName returns the package name printed for the object.
// If its file is in a different package, it returns the package name we're using for this file, plus ".".
// Otherwise it returns the empty string.
func (g *Generator) DefaultPackageName(obj Object) string {
importPath := obj.GoImportPath()
if importPath == g.outputImportPath {
return ""
}
return string(g.GoPackageName(importPath)) + "."
}
// GoPackageName returns the name used for a package.
func (g *Generator) GoPackageName(importPath GoImportPath) GoPackageName {
if name, ok := g.packageNames[importPath]; ok {
return name
}
name := cleanPackageName(baseName(string(importPath)))
for i, orig := 1, name; g.usedPackageNames[name] || isGoPredeclaredIdentifier[string(name)]; i++ {
name = orig + GoPackageName(strconv.Itoa(i))
}
g.packageNames[importPath] = name
g.usedPackageNames[name] = true
return name
}
// AddImport adds a package to the generated file's import section.
// It returns the name used for the package.
func (g *Generator) AddImport(importPath GoImportPath) GoPackageName {
g.addedImports[importPath] = true
return g.GoPackageName(importPath)
}
var globalPackageNames = map[GoPackageName]bool{
"fmt": true,
"math": true,
"proto": true,
}
// Create and remember a guaranteed unique package name. Pkg is the candidate name.
// The FileDescriptor parameter is unused.
func RegisterUniquePackageName(pkg string, f *FileDescriptor) string {
name := cleanPackageName(pkg)
for i, orig := 1, name; globalPackageNames[name]; i++ {
name = orig + GoPackageName(strconv.Itoa(i))
}
globalPackageNames[name] = true
return string(name)
}
var isGoKeyword = map[string]bool{
"break": true,
"case": true,
"chan": true,
"const": true,
"continue": true,
"default": true,
"else": true,
"defer": true,
"fallthrough": true,
"for": true,
"func": true,
"go": true,
"goto": true,
"if": true,
"import": true,
"interface": true,
"map": true,
"package": true,
"range": true,
"return": true,
"select": true,
"struct": true,
"switch": true,
"type": true,
"var": true,
}
var isGoPredeclaredIdentifier = map[string]bool{
"append": true,
"bool": true,
"byte": true,
"cap": true,
"close": true,
"complex": true,
"complex128": true,
"complex64": true,
"copy": true,
"delete": true,
"error": true,
"false": true,
"float32": true,
"float64": true,
"imag": true,
"int": true,
"int16": true,
"int32": true,
"int64": true,
"int8": true,
"iota": true,
"len": true,
"make": true,
"new": true,
"nil": true,
"panic": true,
"print": true,
"println": true,
"real": true,
"recover": true,
"rune": true,
"string": true,
"true": true,
"uint": true,
"uint16": true,
"uint32": true,
"uint64": true,
"uint8": true,
"uintptr": true,
}
func cleanPackageName(name string) GoPackageName {
name = strings.Map(badToUnderscore, name)
// Identifier must not be keyword or predeclared identifier: insert _.
if isGoKeyword[name] {
name = "_" + name
}
// Identifier must not begin with digit: insert _.
if r, _ := utf8.DecodeRuneInString(name); unicode.IsDigit(r) {
name = "_" + name
}
return GoPackageName(name)
}
// defaultGoPackage returns the package name to use,
// derived from the import path of the package we're building code for.
func (g *Generator) defaultGoPackage() GoPackageName {
p := g.PackageImportPath
if i := strings.LastIndex(p, "/"); i >= 0 {
p = p[i+1:]
}
return cleanPackageName(p)
}
// SetPackageNames sets the package name for this run.
// The package name must agree across all files being generated.
// It also defines unique package names for all imported files.
func (g *Generator) SetPackageNames() {
g.outputImportPath = g.genFiles[0].importPath
defaultPackageNames := make(map[GoImportPath]GoPackageName)
for _, f := range g.genFiles {
if _, p, ok := f.goPackageOption(); ok {
defaultPackageNames[f.importPath] = p
}
}
for _, f := range g.genFiles {
if _, p, ok := f.goPackageOption(); ok {
// Source file: option go_package = "quux/bar";
f.packageName = p
} else if p, ok := defaultPackageNames[f.importPath]; ok {
// A go_package option in another file in the same package.
//
// This is a poor choice in general, since every source file should
// contain a go_package option. Supported mainly for historical
// compatibility.
f.packageName = p
} else if p := g.defaultGoPackage(); p != "" {
// Command-line: import_path=quux/bar.
//
// The import_path flag sets a package name for files which don't
// contain a go_package option.
f.packageName = p
} else if p := f.GetPackage(); p != "" {
// Source file: package quux.bar;
f.packageName = cleanPackageName(p)
} else {
// Source filename.
f.packageName = cleanPackageName(baseName(f.GetName()))
}
}
// Check that all files have a consistent package name and import path.
for _, f := range g.genFiles[1:] {
if a, b := g.genFiles[0].importPath, f.importPath; a != b {
g.Fail(fmt.Sprintf("inconsistent package import paths: %v, %v", a, b))
}
if a, b := g.genFiles[0].packageName, f.packageName; a != b {
g.Fail(fmt.Sprintf("inconsistent package names: %v, %v", a, b))
}
}
// Names of support packages. These never vary (if there are conflicts,
// we rename the conflicting package), so this could be removed someday.
g.Pkg = map[string]string{
"fmt": "fmt",
"math": "math",
"proto": "proto",
}
}
// WrapTypes walks the incoming data, wrapping DescriptorProtos, EnumDescriptorProtos
// and FileDescriptorProtos into file-referenced objects within the Generator.
// It also creates the list of files to generate and so should be called before GenerateAllFiles.
func (g *Generator) WrapTypes() {
g.allFiles = make([]*FileDescriptor, 0, len(g.Request.ProtoFile))
g.allFilesByName = make(map[string]*FileDescriptor, len(g.allFiles))
genFileNames := make(map[string]bool)
for _, n := range g.Request.FileToGenerate {
genFileNames[n] = true
}
for _, f := range g.Request.ProtoFile {
fd := &FileDescriptor{
FileDescriptorProto: f,
exported: make(map[Object][]symbol),
proto3: fileIsProto3(f),
}
// The import path may be set in a number of ways.
if substitution, ok := g.ImportMap[f.GetName()]; ok {
// Command-line: M=foo.proto=quux/bar.
//
// Explicit mapping of source file to import path.
fd.importPath = GoImportPath(substitution)
} else if genFileNames[f.GetName()] && g.PackageImportPath != "" {
// Command-line: import_path=quux/bar.
//
// The import_path flag sets the import path for every file that
// we generate code for.
fd.importPath = GoImportPath(g.PackageImportPath)
} else if p, _, _ := fd.goPackageOption(); p != "" {
// Source file: option go_package = "quux/bar";
//
// The go_package option sets the import path. Most users should use this.
fd.importPath = p
} else {
// Source filename.
//
// Last resort when nothing else is available.
fd.importPath = GoImportPath(path.Dir(f.GetName()))
}
// We must wrap the descriptors before we wrap the enums
fd.desc = wrapDescriptors(fd)
g.buildNestedDescriptors(fd.desc)
fd.enum = wrapEnumDescriptors(fd, fd.desc)
g.buildNestedEnums(fd.desc, fd.enum)
fd.ext = wrapExtensions(fd)
extractComments(fd)
g.allFiles = append(g.allFiles, fd)
g.allFilesByName[f.GetName()] = fd
}
for _, fd := range g.allFiles {
fd.imp = wrapImported(fd, g)
}
g.genFiles = make([]*FileDescriptor, 0, len(g.Request.FileToGenerate))
for _, fileName := range g.Request.FileToGenerate {
fd := g.allFilesByName[fileName]
if fd == nil {
g.Fail("could not find file named", fileName)
}
g.genFiles = append(g.genFiles, fd)
}
}
// Scan the descriptors in this file. For each one, build the slice of nested descriptors
func (g *Generator) buildNestedDescriptors(descs []*Descriptor) {
for _, desc := range descs {
if len(desc.NestedType) != 0 {
for _, nest := range descs {
if nest.parent == desc {
desc.nested = append(desc.nested, nest)
}
}
if len(desc.nested) != len(desc.NestedType) {
g.Fail("internal error: nesting failure for", desc.GetName())
}
}
}
}
func (g *Generator) buildNestedEnums(descs []*Descriptor, enums []*EnumDescriptor) {
for _, desc := range descs {
if len(desc.EnumType) != 0 {
for _, enum := range enums {
if enum.parent == desc {
desc.enums = append(desc.enums, enum)
}
}
if len(desc.enums) != len(desc.EnumType) {
g.Fail("internal error: enum nesting failure for", desc.GetName())
}
}
}
}
// Construct the Descriptor
func newDescriptor(desc *descriptor.DescriptorProto, parent *Descriptor, file *FileDescriptor, index int) *Descriptor {
d := &Descriptor{
common: common{file},
DescriptorProto: desc,
parent: parent,
index: index,
}
if parent == nil {
d.path = fmt.Sprintf("%d,%d", messagePath, index)
} else {
d.path = fmt.Sprintf("%s,%d,%d", parent.path, messageMessagePath, index)
}
// The only way to distinguish a group from a message is whether
// the containing message has a TYPE_GROUP field that matches.
if parent != nil {
parts := d.TypeName()
if file.Package != nil {
parts = append([]string{*file.Package}, parts...)
}
exp := "." + strings.Join(parts, ".")
for _, field := range parent.Field {
if field.GetType() == descriptor.FieldDescriptorProto_TYPE_GROUP && field.GetTypeName() == exp {
d.group = true
break
}
}
}
for _, field := range desc.Extension {
d.ext = append(d.ext, &ExtensionDescriptor{common{file}, field, d})
}
return d
}
// Return a slice of all the Descriptors defined within this file
func wrapDescriptors(file *FileDescriptor) []*Descriptor {
sl := make([]*Descriptor, 0, len(file.MessageType)+10)
for i, desc := range file.MessageType {
sl = wrapThisDescriptor(sl, desc, nil, file, i)
}
return sl
}
// Wrap this Descriptor, recursively
func wrapThisDescriptor(sl []*Descriptor, desc *descriptor.DescriptorProto, parent *Descriptor, file *FileDescriptor, index int) []*Descriptor {
sl = append(sl, newDescriptor(desc, parent, file, index))
me := sl[len(sl)-1]
for i, nested := range desc.NestedType {
sl = wrapThisDescriptor(sl, nested, me, file, i)
}
return sl
}
// Construct the EnumDescriptor
func newEnumDescriptor(desc *descriptor.EnumDescriptorProto, parent *Descriptor, file *FileDescriptor, index int) *EnumDescriptor {
ed := &EnumDescriptor{
common: common{file},
EnumDescriptorProto: desc,
parent: parent,
index: index,
}
if parent == nil {
ed.path = fmt.Sprintf("%d,%d", enumPath, index)
} else {
ed.path = fmt.Sprintf("%s,%d,%d", parent.path, messageEnumPath, index)
}
return ed
}
// Return a slice of all the EnumDescriptors defined within this file
func wrapEnumDescriptors(file *FileDescriptor, descs []*Descriptor) []*EnumDescriptor {
sl := make([]*EnumDescriptor, 0, len(file.EnumType)+10)
// Top-level enums.
for i, enum := range file.EnumType {
sl = append(sl, newEnumDescriptor(enum, nil, file, i))
}
// Enums within messages. Enums within embedded messages appear in the outer-most message.
for _, nested := range descs {
for i, enum := range nested.EnumType {
sl = append(sl, newEnumDescriptor(enum, nested, file, i))
}
}
return sl
}
// Return a slice of all the top-level ExtensionDescriptors defined within this file.
func wrapExtensions(file *FileDescriptor) []*ExtensionDescriptor {
var sl []*ExtensionDescriptor
for _, field := range file.Extension {
sl = append(sl, &ExtensionDescriptor{common{file}, field, nil})
}
return sl
}
// Return a slice of all the types that are publicly imported into this file.
func wrapImported(file *FileDescriptor, g *Generator) (sl []*ImportedDescriptor) {
for _, index := range file.PublicDependency {
df := g.fileByName(file.Dependency[index])
for _, d := range df.desc {
if d.GetOptions().GetMapEntry() {
continue
}
sl = append(sl, &ImportedDescriptor{common{file}, d})
}
for _, e := range df.enum {
sl = append(sl, &ImportedDescriptor{common{file}, e})
}
for _, ext := range df.ext {
sl = append(sl, &ImportedDescriptor{common{file}, ext})
}
}
return
}
func extractComments(file *FileDescriptor) {
file.comments = make(map[string]*descriptor.SourceCodeInfo_Location)
for _, loc := range file.GetSourceCodeInfo().GetLocation() {
if loc.LeadingComments == nil {
continue
}
var p []string
for _, n := range loc.Path {
p = append(p, strconv.Itoa(int(n)))
}
file.comments[strings.Join(p, ",")] = loc
}
}
// BuildTypeNameMap builds the map from fully qualified type names to objects.
// The key names for the map come from the input data, which puts a period at the beginning.
// It should be called after SetPackageNames and before GenerateAllFiles.
func (g *Generator) BuildTypeNameMap() {
g.typeNameToObject = make(map[string]Object)
for _, f := range g.allFiles {
// The names in this loop are defined by the proto world, not us, so the
// package name may be empty. If so, the dotted package name of X will
// be ".X"; otherwise it will be ".pkg.X".
dottedPkg := "." + f.GetPackage()
if dottedPkg != "." {
dottedPkg += "."
}
for _, enum := range f.enum {
name := dottedPkg + dottedSlice(enum.TypeName())
g.typeNameToObject[name] = enum
}
for _, desc := range f.desc {
name := dottedPkg + dottedSlice(desc.TypeName())
g.typeNameToObject[name] = desc
}
}
}
// ObjectNamed, given a fully-qualified input type name as it appears in the input data,
// returns the descriptor for the message or enum with that name.
func (g *Generator) ObjectNamed(typeName string) Object {
o, ok := g.typeNameToObject[typeName]
if !ok {
g.Fail("can't find object with type", typeName)
}
return o
}
// AnnotatedAtoms is a list of atoms (as consumed by P) that records the file name and proto AST path from which they originated.
type AnnotatedAtoms struct {
source string
path string
atoms []interface{}
}
// Annotate records the file name and proto AST path of a list of atoms
// so that a later call to P can emit a link from each atom to its origin.
func Annotate(file *FileDescriptor, path string, atoms ...interface{}) *AnnotatedAtoms {
return &AnnotatedAtoms{source: *file.Name, path: path, atoms: atoms}
}
// printAtom prints the (atomic, non-annotation) argument to the generated output.
func (g *Generator) printAtom(v interface{}) {
switch v := v.(type) {
case string:
g.WriteString(v)
case *string:
g.WriteString(*v)
case bool:
fmt.Fprint(g, v)
case *bool:
fmt.Fprint(g, *v)
case int:
fmt.Fprint(g, v)
case *int32:
fmt.Fprint(g, *v)
case *int64:
fmt.Fprint(g, *v)
case float64:
fmt.Fprint(g, v)
case *float64:
fmt.Fprint(g, *v)
case GoPackageName:
g.WriteString(string(v))
case GoImportPath:
g.WriteString(strconv.Quote(string(v)))
default:
g.Fail(fmt.Sprintf("unknown type in printer: %T", v))
}
}
// P prints the arguments to the generated output. It handles strings and int32s, plus
// handling indirections because they may be *string, etc. Any inputs of type AnnotatedAtoms may emit
// annotations in a .meta file in addition to outputting the atoms themselves (if g.annotateCode
// is true).
func (g *Generator) P(str ...interface{}) {
if !g.writeOutput {
return
}
g.WriteString(g.indent)
for _, v := range str {
switch v := v.(type) {
case *AnnotatedAtoms:
begin := int32(g.Len())
for _, v := range v.atoms {
g.printAtom(v)
}
if g.annotateCode {
end := int32(g.Len())
var path []int32
for _, token := range strings.Split(v.path, ",") {
val, err := strconv.ParseInt(token, 10, 32)
if err != nil {
g.Fail("could not parse proto AST path: ", err.Error())
}
path = append(path, int32(val))
}
g.annotations = append(g.annotations, &descriptor.GeneratedCodeInfo_Annotation{
Path: path,
SourceFile: &v.source,
Begin: &begin,
End: &end,
})
}
default:
g.printAtom(v)
}
}
g.WriteByte('\n')
}
// addInitf stores the given statement to be printed inside the file's init function.
// The statement is given as a format specifier and arguments.
func (g *Generator) addInitf(stmt string, a ...interface{}) {
g.init = append(g.init, fmt.Sprintf(stmt, a...))
}
// In Indents the output one tab stop.
func (g *Generator) In() { g.indent += "\t" }
// Out unindents the output one tab stop.
func (g *Generator) Out() {
if len(g.indent) > 0 {
g.indent = g.indent[1:]
}
}
// GenerateAllFiles generates the output for all the files we're outputting.
func (g *Generator) GenerateAllFiles() {
// Initialize the plugins
for _, p := range plugins {
p.Init(g)
}
// Generate the output. The generator runs for every file, even the files
// that we don't generate output for, so that we can collate the full list
// of exported symbols to support public imports.
genFileMap := make(map[*FileDescriptor]bool, len(g.genFiles))
for _, file := range g.genFiles {
genFileMap[file] = true
}
for _, file := range g.allFiles {
g.Reset()
g.annotations = nil
g.writeOutput = genFileMap[file]
g.generate(file)
if !g.writeOutput {
continue
}
fname := file.goFileName(g.pathType)
g.Response.File = append(g.Response.File, &plugin.CodeGeneratorResponse_File{
Name: proto.String(fname),
Content: proto.String(g.String()),
})
if g.annotateCode {
// Store the generated code annotations in text, as the protoc plugin protocol requires that
// strings contain valid UTF-8.
g.Response.File = append(g.Response.File, &plugin.CodeGeneratorResponse_File{
Name: proto.String(file.goFileName(g.pathType) + ".meta"),
Content: proto.String(proto.CompactTextString(&descriptor.GeneratedCodeInfo{Annotation: g.annotations})),
})
}
}
}
// Run all the plugins associated with the file.
func (g *Generator) runPlugins(file *FileDescriptor) {
for _, p := range plugins {
p.Generate(file)
}
}
// Fill the response protocol buffer with the generated output for all the files we're
// supposed to generate.
func (g *Generator) generate(file *FileDescriptor) {
g.file = file
g.usedPackages = make(map[GoImportPath]bool)
g.packageNames = make(map[GoImportPath]GoPackageName)
g.usedPackageNames = make(map[GoPackageName]bool)
g.addedImports = make(map[GoImportPath]bool)
for name := range globalPackageNames {
g.usedPackageNames[name] = true
}
g.P("// This is a compile-time assertion to ensure that this generated file")
g.P("// is compatible with the proto package it is being compiled against.")
g.P("// A compilation error at this line likely means your copy of the")
g.P("// proto package needs to be updated.")
g.P("const _ = ", g.Pkg["proto"], ".ProtoPackageIsVersion", generatedCodeVersion, " // please upgrade the proto package")
g.P()
for _, td := range g.file.imp {
g.generateImported(td)
}
for _, enum := range g.file.enum {
g.generateEnum(enum)
}
for _, desc := range g.file.desc {
// Don't generate virtual messages for maps.
if desc.GetOptions().GetMapEntry() {
continue
}
g.generateMessage(desc)
}
for _, ext := range g.file.ext {
g.generateExtension(ext)
}
g.generateInitFunction()
g.generateFileDescriptor(file)
// Run the plugins before the imports so we know which imports are necessary.
g.runPlugins(file)
// Generate header and imports last, though they appear first in the output.
rem := g.Buffer
remAnno := g.annotations
g.Buffer = new(bytes.Buffer)
g.annotations = nil
g.generateHeader()
g.generateImports()
if !g.writeOutput {
return
}
// Adjust the offsets for annotations displaced by the header and imports.
for _, anno := range remAnno {
*anno.Begin += int32(g.Len())
*anno.End += int32(g.Len())
g.annotations = append(g.annotations, anno)
}
g.Write(rem.Bytes())
// Reformat generated code and patch annotation locations.
fset := token.NewFileSet()
original := g.Bytes()
if g.annotateCode {
// make a copy independent of g; we'll need it after Reset.
original = append([]byte(nil), original...)
}
fileAST, err := parser.ParseFile(fset, "", original, parser.ParseComments)
if err != nil {
// Print out the bad code with line numbers.
// This should never happen in practice, but it can while changing generated code,
// so consider this a debugging aid.
var src bytes.Buffer
s := bufio.NewScanner(bytes.NewReader(original))
for line := 1; s.Scan(); line++ {
fmt.Fprintf(&src, "%5d\t%s\n", line, s.Bytes())
}
g.Fail("bad Go source code was generated:", err.Error(), "\n"+src.String())
}
ast.SortImports(fset, fileAST)
g.Reset()
err = (&printer.Config{Mode: printer.TabIndent | printer.UseSpaces, Tabwidth: 8}).Fprint(g, fset, fileAST)
if err != nil {
g.Fail("generated Go source code could not be reformatted:", err.Error())
}
if g.annotateCode {
m, err := remap.Compute(original, g.Bytes())
if err != nil {
g.Fail("formatted generated Go source code could not be mapped back to the original code:", err.Error())
}
for _, anno := range g.annotations {
new, ok := m.Find(int(*anno.Begin), int(*anno.End))
if !ok {
g.Fail("span in formatted generated Go source code could not be mapped back to the original code")
}
*anno.Begin = int32(new.Pos)
*anno.End = int32(new.End)
}
}
}
// Generate the header, including package definition
func (g *Generator) generateHeader() {
g.P("// Code generated by protoc-gen-go. DO NOT EDIT.")
if g.file.GetOptions().GetDeprecated() {
g.P("// ", g.file.Name, " is a deprecated file.")
} else {
g.P("// source: ", g.file.Name)
}
g.P()
g.PrintComments(strconv.Itoa(packagePath))
g.P()
g.P("package ", g.file.packageName)
g.P()
}
// deprecationComment is the standard comment added to deprecated
// messages, fields, enums, and enum values.
var deprecationComment = "// Deprecated: Do not use."
// PrintComments prints any comments from the source .proto file.
// The path is a comma-separated list of integers.
// It returns an indication of whether any comments were printed.
// See descriptor.proto for its format.
func (g *Generator) PrintComments(path string) bool {
if !g.writeOutput {
return false
}
if c, ok := g.makeComments(path); ok {
g.P(c)
return true
}
return false
}
// makeComments generates the comment string for the field, no "\n" at the end
func (g *Generator) makeComments(path string) (string, bool) {
loc, ok := g.file.comments[path]
if !ok {
return "", false
}
w := new(bytes.Buffer)
nl := ""
for _, line := range strings.Split(strings.TrimSuffix(loc.GetLeadingComments(), "\n"), "\n") {
fmt.Fprintf(w, "%s//%s", nl, line)
nl = "\n"
}
return w.String(), true
}
func (g *Generator) fileByName(filename string) *FileDescriptor {
return g.allFilesByName[filename]
}
// weak returns whether the ith import of the current file is a weak import.
func (g *Generator) weak(i int32) bool {
for _, j := range g.file.WeakDependency {
if j == i {
return true
}
}
return false
}
// Generate the imports
func (g *Generator) generateImports() {
imports := make(map[GoImportPath]GoPackageName)
for i, s := range g.file.Dependency {
fd := g.fileByName(s)
importPath := fd.importPath
// Do not import our own package.
if importPath == g.file.importPath {
continue
}
// Do not import weak imports.
if g.weak(int32(i)) {
continue
}
// Do not import a package twice.
if _, ok := imports[importPath]; ok {
continue
}
// We need to import all the dependencies, even if we don't reference them,
// because other code and tools depend on having the full transitive closure
// of protocol buffer types in the binary.
packageName := g.GoPackageName(importPath)
if _, ok := g.usedPackages[importPath]; !ok {
packageName = "_"
}
imports[importPath] = packageName
}
for importPath := range g.addedImports {
imports[importPath] = g.GoPackageName(importPath)
}
// We almost always need a proto import. Rather than computing when we
// do, which is tricky when there's a plugin, just import it and
// reference it later. The same argument applies to the fmt and math packages.
g.P("import (")
g.P(g.Pkg["fmt"] + ` "fmt"`)
g.P(g.Pkg["math"] + ` "math"`)
g.P(g.Pkg["proto"]+" ", GoImportPath(g.ImportPrefix)+"github.com/golang/protobuf/proto")
for importPath, packageName := range imports {
g.P(packageName, " ", GoImportPath(g.ImportPrefix)+importPath)
}
g.P(")")
g.P()
// TODO: may need to worry about uniqueness across plugins
for _, p := range plugins {
p.GenerateImports(g.file)
g.P()
}
g.P("// Reference imports to suppress errors if they are not otherwise used.")
g.P("var _ = ", g.Pkg["proto"], ".Marshal")
g.P("var _ = ", g.Pkg["fmt"], ".Errorf")
g.P("var _ = ", g.Pkg["math"], ".Inf")
g.P()
}
func (g *Generator) generateImported(id *ImportedDescriptor) {
df := id.o.File()
filename := *df.Name
if df.importPath == g.file.importPath {
// Don't generate type aliases for files in the same Go package as this one.
return
}
if !supportTypeAliases {
g.Fail(fmt.Sprintf("%s: public imports require at least go1.9", filename))
}
g.usedPackages[df.importPath] = true
for _, sym := range df.exported[id.o] {
sym.GenerateAlias(g, filename, g.GoPackageName(df.importPath))
}
g.P()
}
// Generate the enum definitions for this EnumDescriptor.
func (g *Generator) generateEnum(enum *EnumDescriptor) {
// The full type name
typeName := enum.TypeName()
// The full type name, CamelCased.
ccTypeName := CamelCaseSlice(typeName)
ccPrefix := enum.prefix()
deprecatedEnum := ""
if enum.GetOptions().GetDeprecated() {
deprecatedEnum = deprecationComment
}
g.PrintComments(enum.path)
g.P("type ", Annotate(enum.file, enum.path, ccTypeName), " int32", deprecatedEnum)
g.file.addExport(enum, enumSymbol{ccTypeName, enum.proto3()})
g.P("const (")
for i, e := range enum.Value {
etorPath := fmt.Sprintf("%s,%d,%d", enum.path, enumValuePath, i)
g.PrintComments(etorPath)
deprecatedValue := ""
if e.GetOptions().GetDeprecated() {
deprecatedValue = deprecationComment
}
name := ccPrefix + *e.Name
g.P(Annotate(enum.file, etorPath, name), " ", ccTypeName, " = ", e.Number, " ", deprecatedValue)
g.file.addExport(enum, constOrVarSymbol{name, "const", ccTypeName})
}
g.P(")")
g.P()
g.P("var ", ccTypeName, "_name = map[int32]string{")
generated := make(map[int32]bool) // avoid duplicate values
for _, e := range enum.Value {
duplicate := ""
if _, present := generated[*e.Number]; present {
duplicate = "// Duplicate value: "
}
g.P(duplicate, e.Number, ": ", strconv.Quote(*e.Name), ",")
generated[*e.Number] = true
}
g.P("}")
g.P()
g.P("var ", ccTypeName, "_value = map[string]int32{")
for _, e := range enum.Value {
g.P(strconv.Quote(*e.Name), ": ", e.Number, ",")
}
g.P("}")
g.P()
if !enum.proto3() {
g.P("func (x ", ccTypeName, ") Enum() *", ccTypeName, " {")
g.P("p := new(", ccTypeName, ")")
g.P("*p = x")
g.P("return p")
g.P("}")
g.P()
}
g.P("func (x ", ccTypeName, ") String() string {")
g.P("return ", g.Pkg["proto"], ".EnumName(", ccTypeName, "_name, int32(x))")
g.P("}")
g.P()
if !enum.proto3() {
g.P("func (x *", ccTypeName, ") UnmarshalJSON(data []byte) error {")
g.P("value, err := ", g.Pkg["proto"], ".UnmarshalJSONEnum(", ccTypeName, `_value, data, "`, ccTypeName, `")`)
g.P("if err != nil {")
g.P("return err")
g.P("}")
g.P("*x = ", ccTypeName, "(value)")
g.P("return nil")
g.P("}")
g.P()
}
var indexes []string
for m := enum.parent; m != nil; m = m.parent {
// XXX: skip groups?
indexes = append([]string{strconv.Itoa(m.index)}, indexes...)
}
indexes = append(indexes, strconv.Itoa(enum.index))
g.P("func (", ccTypeName, ") EnumDescriptor() ([]byte, []int) {")
g.P("return ", g.file.VarName(), ", []int{", strings.Join(indexes, ", "), "}")
g.P("}")
g.P()
if enum.file.GetPackage() == "google.protobuf" && enum.GetName() == "NullValue" {
g.P("func (", ccTypeName, `) XXX_WellKnownType() string { return "`, enum.GetName(), `" }`)
g.P()
}
g.generateEnumRegistration(enum)
}
// The tag is a string like "varint,2,opt,name=fieldname,def=7" that
// identifies details of the field for the protocol buffer marshaling and unmarshaling
// code. The fields are:
// wire encoding
// protocol tag number
// opt,req,rep for optional, required, or repeated
// packed whether the encoding is "packed" (optional; repeated primitives only)
// name= the original declared name
// enum= the name of the enum type if it is an enum-typed field.
// proto3 if this field is in a proto3 message
// def= string representation of the default value, if any.
// The default value must be in a representation that can be used at run-time
// to generate the default value. Thus bools become 0 and 1, for instance.
func (g *Generator) goTag(message *Descriptor, field *descriptor.FieldDescriptorProto, wiretype string) string {
optrepreq := ""
switch {
case isOptional(field):
optrepreq = "opt"
case isRequired(field):
optrepreq = "req"
case isRepeated(field):
optrepreq = "rep"
}
var defaultValue string
if dv := field.DefaultValue; dv != nil { // set means an explicit default
defaultValue = *dv
// Some types need tweaking.
switch *field.Type {
case descriptor.FieldDescriptorProto_TYPE_BOOL:
if defaultValue == "true" {
defaultValue = "1"
} else {
defaultValue = "0"
}
case descriptor.FieldDescriptorProto_TYPE_STRING,
descriptor.FieldDescriptorProto_TYPE_BYTES:
// Nothing to do. Quoting is done for the whole tag.
case descriptor.FieldDescriptorProto_TYPE_ENUM:
// For enums we need to provide the integer constant.
obj := g.ObjectNamed(field.GetTypeName())
if id, ok := obj.(*ImportedDescriptor); ok {
// It is an enum that was publicly imported.
// We need the underlying type.
obj = id.o
}
enum, ok := obj.(*EnumDescriptor)
if !ok {
log.Printf("obj is a %T", obj)
if id, ok := obj.(*ImportedDescriptor); ok {
log.Printf("id.o is a %T", id.o)
}
g.Fail("unknown enum type", CamelCaseSlice(obj.TypeName()))
}
defaultValue = enum.integerValueAsString(defaultValue)
case descriptor.FieldDescriptorProto_TYPE_FLOAT:
if def := defaultValue; def != "inf" && def != "-inf" && def != "nan" {
if f, err := strconv.ParseFloat(defaultValue, 32); err == nil {
defaultValue = fmt.Sprint(float32(f))
}
}
case descriptor.FieldDescriptorProto_TYPE_DOUBLE:
if def := defaultValue; def != "inf" && def != "-inf" && def != "nan" {
if f, err := strconv.ParseFloat(defaultValue, 64); err == nil {
defaultValue = fmt.Sprint(f)
}
}
}
defaultValue = ",def=" + defaultValue
}
enum := ""
if *field.Type == descriptor.FieldDescriptorProto_TYPE_ENUM {
// We avoid using obj.GoPackageName(), because we want to use the
// original (proto-world) package name.
obj := g.ObjectNamed(field.GetTypeName())
if id, ok := obj.(*ImportedDescriptor); ok {
obj = id.o
}
enum = ",enum="
if pkg := obj.File().GetPackage(); pkg != "" {
enum += pkg + "."
}
enum += CamelCaseSlice(obj.TypeName())
}
packed := ""
if (field.Options != nil && field.Options.GetPacked()) ||
// Per https://developers.google.com/protocol-buffers/docs/proto3#simple:
// "In proto3, repeated fields of scalar numeric types use packed encoding by default."
(message.proto3() && (field.Options == nil || field.Options.Packed == nil) &&
isRepeated(field) && isScalar(field)) {
packed = ",packed"
}
fieldName := field.GetName()
name := fieldName
if *field.Type == descriptor.FieldDescriptorProto_TYPE_GROUP {
// We must use the type name for groups instead of
// the field name to preserve capitalization.
// type_name in FieldDescriptorProto is fully-qualified,
// but we only want the local part.
name = *field.TypeName
if i := strings.LastIndex(name, "."); i >= 0 {
name = name[i+1:]
}
}
if json := field.GetJsonName(); field.Extendee == nil && json != "" && json != name {
// TODO: escaping might be needed, in which case
// perhaps this should be in its own "json" tag.
name += ",json=" + json
}
name = ",name=" + name
if message.proto3() {
name += ",proto3"
}
oneof := ""
if field.OneofIndex != nil {
oneof = ",oneof"
}
return strconv.Quote(fmt.Sprintf("%s,%d,%s%s%s%s%s%s",
wiretype,
field.GetNumber(),
optrepreq,
packed,
name,
enum,
oneof,
defaultValue))
}
func needsStar(typ descriptor.FieldDescriptorProto_Type) bool {
switch typ {
case descriptor.FieldDescriptorProto_TYPE_GROUP:
return false
case descriptor.FieldDescriptorProto_TYPE_MESSAGE:
return false
case descriptor.FieldDescriptorProto_TYPE_BYTES:
return false
}
return true
}
// TypeName is the printed name appropriate for an item. If the object is in the current file,
// TypeName drops the package name and underscores the rest.
// Otherwise the object is from another package; and the result is the underscored
// package name followed by the item name.
// The result always has an initial capital.
func (g *Generator) TypeName(obj Object) string {
return g.DefaultPackageName(obj) + CamelCaseSlice(obj.TypeName())
}
// GoType returns a string representing the type name, and the wire type
func (g *Generator) GoType(message *Descriptor, field *descriptor.FieldDescriptorProto) (typ string, wire string) {
// TODO: Options.
switch *field.Type {
case descriptor.FieldDescriptorProto_TYPE_DOUBLE:
typ, wire = "float64", "fixed64"
case descriptor.FieldDescriptorProto_TYPE_FLOAT:
typ, wire = "float32", "fixed32"
case descriptor.FieldDescriptorProto_TYPE_INT64:
typ, wire = "int64", "varint"
case descriptor.FieldDescriptorProto_TYPE_UINT64:
typ, wire = "uint64", "varint"
case descriptor.FieldDescriptorProto_TYPE_INT32:
typ, wire = "int32", "varint"
case descriptor.FieldDescriptorProto_TYPE_UINT32:
typ, wire = "uint32", "varint"
case descriptor.FieldDescriptorProto_TYPE_FIXED64:
typ, wire = "uint64", "fixed64"
case descriptor.FieldDescriptorProto_TYPE_FIXED32:
typ, wire = "uint32", "fixed32"
case descriptor.FieldDescriptorProto_TYPE_BOOL:
typ, wire = "bool", "varint"
case descriptor.FieldDescriptorProto_TYPE_STRING:
typ, wire = "string", "bytes"
case descriptor.FieldDescriptorProto_TYPE_GROUP:
desc := g.ObjectNamed(field.GetTypeName())
typ, wire = "*"+g.TypeName(desc), "group"
case descriptor.FieldDescriptorProto_TYPE_MESSAGE:
desc := g.ObjectNamed(field.GetTypeName())
typ, wire = "*"+g.TypeName(desc), "bytes"
case descriptor.FieldDescriptorProto_TYPE_BYTES:
typ, wire = "[]byte", "bytes"
case descriptor.FieldDescriptorProto_TYPE_ENUM:
desc := g.ObjectNamed(field.GetTypeName())
typ, wire = g.TypeName(desc), "varint"
case descriptor.FieldDescriptorProto_TYPE_SFIXED32:
typ, wire = "int32", "fixed32"
case descriptor.FieldDescriptorProto_TYPE_SFIXED64:
typ, wire = "int64", "fixed64"
case descriptor.FieldDescriptorProto_TYPE_SINT32:
typ, wire = "int32", "zigzag32"
case descriptor.FieldDescriptorProto_TYPE_SINT64:
typ, wire = "int64", "zigzag64"
default:
g.Fail("unknown type for", field.GetName())
}
if isRepeated(field) {
typ = "[]" + typ
} else if message != nil && message.proto3() {
return
} else if field.OneofIndex != nil && message != nil {
return
} else if needsStar(*field.Type) {
typ = "*" + typ
}
return
}
func (g *Generator) RecordTypeUse(t string) {
if _, ok := g.typeNameToObject[t]; !ok {
return
}
importPath := g.ObjectNamed(t).GoImportPath()
if importPath == g.outputImportPath {
// Don't record use of objects in our package.
return
}
g.AddImport(importPath)
g.usedPackages[importPath] = true
}
// Method names that may be generated. Fields with these names get an
// underscore appended. Any change to this set is a potential incompatible
// API change because it changes generated field names.
var methodNames = [...]string{
"Reset",
"String",
"ProtoMessage",
"Marshal",
"Unmarshal",
"ExtensionRangeArray",
"ExtensionMap",
"Descriptor",
}
// Names of messages in the `google.protobuf` package for which
// we will generate XXX_WellKnownType methods.
var wellKnownTypes = map[string]bool{
"Any": true,
"Duration": true,
"Empty": true,
"Struct": true,
"Timestamp": true,
"Value": true,
"ListValue": true,
"DoubleValue": true,
"FloatValue": true,
"Int64Value": true,
"UInt64Value": true,
"Int32Value": true,
"UInt32Value": true,
"BoolValue": true,
"StringValue": true,
"BytesValue": true,
}
// getterDefault finds the default value for the field to return from a getter,
// regardless of if it's a built in default or explicit from the source. Returns e.g. "nil", `""`, "Default_MessageType_FieldName"
func (g *Generator) getterDefault(field *descriptor.FieldDescriptorProto, goMessageType string) string {
if isRepeated(field) {
return "nil"
}
if def := field.GetDefaultValue(); def != "" {
defaultConstant := g.defaultConstantName(goMessageType, field.GetName())
if *field.Type != descriptor.FieldDescriptorProto_TYPE_BYTES {
return defaultConstant
}
return "append([]byte(nil), " + defaultConstant + "...)"
}
switch *field.Type {
case descriptor.FieldDescriptorProto_TYPE_BOOL:
return "false"
case descriptor.FieldDescriptorProto_TYPE_STRING:
return `""`
case descriptor.FieldDescriptorProto_TYPE_GROUP, descriptor.FieldDescriptorProto_TYPE_MESSAGE, descriptor.FieldDescriptorProto_TYPE_BYTES:
return "nil"
case descriptor.FieldDescriptorProto_TYPE_ENUM:
obj := g.ObjectNamed(field.GetTypeName())
var enum *EnumDescriptor
if id, ok := obj.(*ImportedDescriptor); ok {
// The enum type has been publicly imported.
enum, _ = id.o.(*EnumDescriptor)
} else {
enum, _ = obj.(*EnumDescriptor)
}
if enum == nil {
log.Printf("don't know how to generate getter for %s", field.GetName())
return "nil"
}
if len(enum.Value) == 0 {
return "0 // empty enum"
}
first := enum.Value[0].GetName()
return g.DefaultPackageName(obj) + enum.prefix() + first
default:
return "0"
}
}
// defaultConstantName builds the name of the default constant from the message
// type name and the untouched field name, e.g. "Default_MessageType_FieldName"
func (g *Generator) defaultConstantName(goMessageType, protoFieldName string) string {
return "Default_" + goMessageType + "_" + CamelCase(protoFieldName)
}
// The different types of fields in a message and how to actually print them
// Most of the logic for generateMessage is in the methods of these types.
//
// Note that the content of the field is irrelevant, a simpleField can contain
// anything from a scalar to a group (which is just a message).
//
// Extension fields (and message sets) are however handled separately.
//
// simpleField - a field that is neiter weak nor oneof, possibly repeated
// oneofField - field containing list of subfields:
// - oneofSubField - a field within the oneof
// msgCtx contains the context for the generator functions.
type msgCtx struct {
goName string // Go struct name of the message, e.g. MessageName
message *Descriptor // The descriptor for the message
}
// fieldCommon contains data common to all types of fields.
type fieldCommon struct {
goName string // Go name of field, e.g. "FieldName" or "Descriptor_"
protoName string // Name of field in proto language, e.g. "field_name" or "descriptor"
getterName string // Name of the getter, e.g. "GetFieldName" or "GetDescriptor_"
goType string // The Go type as a string, e.g. "*int32" or "*OtherMessage"
tags string // The tag string/annotation for the type, e.g. `protobuf:"varint,8,opt,name=region_id,json=regionId"`
fullPath string // The full path of the field as used by Annotate etc, e.g. "4,0,2,0"
}
// getProtoName gets the proto name of a field, e.g. "field_name" or "descriptor".
func (f *fieldCommon) getProtoName() string {
return f.protoName
}
// getGoType returns the go type of the field as a string, e.g. "*int32".
func (f *fieldCommon) getGoType() string {
return f.goType
}
// simpleField is not weak, not a oneof, not an extension. Can be required, optional or repeated.
type simpleField struct {
fieldCommon
protoTypeName string // Proto type name, empty if primitive, e.g. ".google.protobuf.Duration"
protoType descriptor.FieldDescriptorProto_Type // Actual type enum value, e.g. descriptor.FieldDescriptorProto_TYPE_FIXED64
deprecated string // Deprecation comment, if any, e.g. "// Deprecated: Do not use."
getterDef string // Default for getters, e.g. "nil", `""` or "Default_MessageType_FieldName"
protoDef string // Default value as defined in the proto file, e.g "yoshi" or "5"
comment string // The full comment for the field, e.g. "// Useful information"
}
// decl prints the declaration of the field in the struct (if any).
func (f *simpleField) decl(g *Generator, mc *msgCtx) {
g.P(f.comment, Annotate(mc.message.file, f.fullPath, f.goName), "\t", f.goType, "\t`", f.tags, "`", f.deprecated)
}
// getter prints the getter for the field.
func (f *simpleField) getter(g *Generator, mc *msgCtx) {
star := ""
tname := f.goType
if needsStar(f.protoType) && tname[0] == '*' {
tname = tname[1:]
star = "*"
}
if f.deprecated != "" {
g.P(f.deprecated)
}
g.P("func (m *", mc.goName, ") ", Annotate(mc.message.file, f.fullPath, f.getterName), "() "+tname+" {")
if f.getterDef == "nil" { // Simpler getter
g.P("if m != nil {")
g.P("return m." + f.goName)
g.P("}")
g.P("return nil")
g.P("}")
g.P()
return
}
if mc.message.proto3() {
g.P("if m != nil {")
} else {
g.P("if m != nil && m." + f.goName + " != nil {")
}
g.P("return " + star + "m." + f.goName)
g.P("}")
g.P("return ", f.getterDef)
g.P("}")
g.P()
}
// setter prints the setter method of the field.
func (f *simpleField) setter(g *Generator, mc *msgCtx) {
// No setter for regular fields yet
}
// getProtoDef returns the default value explicitly stated in the proto file, e.g "yoshi" or "5".
func (f *simpleField) getProtoDef() string {
return f.protoDef
}
// getProtoTypeName returns the protobuf type name for the field as returned by field.GetTypeName(), e.g. ".google.protobuf.Duration".
func (f *simpleField) getProtoTypeName() string {
return f.protoTypeName
}
// getProtoType returns the *field.Type value, e.g. descriptor.FieldDescriptorProto_TYPE_FIXED64.
func (f *simpleField) getProtoType() descriptor.FieldDescriptorProto_Type {
return f.protoType
}
// oneofSubFields are kept slize held by each oneofField. They do not appear in the top level slize of fields for the message.
type oneofSubField struct {
fieldCommon
protoTypeName string // Proto type name, empty if primitive, e.g. ".google.protobuf.Duration"
protoType descriptor.FieldDescriptorProto_Type // Actual type enum value, e.g. descriptor.FieldDescriptorProto_TYPE_FIXED64
oneofTypeName string // Type name of the enclosing struct, e.g. "MessageName_FieldName"
fieldNumber int // Actual field number, as defined in proto, e.g. 12
getterDef string // Default for getters, e.g. "nil", `""` or "Default_MessageType_FieldName"
protoDef string // Default value as defined in the proto file, e.g "yoshi" or "5"
deprecated string // Deprecation comment, if any.
}
// typedNil prints a nil casted to the pointer to this field.
// - for XXX_OneofWrappers
func (f *oneofSubField) typedNil(g *Generator) {
g.P("(*", f.oneofTypeName, ")(nil),")
}
// getProtoDef returns the default value explicitly stated in the proto file, e.g "yoshi" or "5".
func (f *oneofSubField) getProtoDef() string {
return f.protoDef
}
// getProtoTypeName returns the protobuf type name for the field as returned by field.GetTypeName(), e.g. ".google.protobuf.Duration".
func (f *oneofSubField) getProtoTypeName() string {
return f.protoTypeName
}
// getProtoType returns the *field.Type value, e.g. descriptor.FieldDescriptorProto_TYPE_FIXED64.
func (f *oneofSubField) getProtoType() descriptor.FieldDescriptorProto_Type {
return f.protoType
}
// oneofField represents the oneof on top level.
// The alternative fields within the oneof are represented by oneofSubField.
type oneofField struct {
fieldCommon
subFields []*oneofSubField // All the possible oneof fields
comment string // The full comment for the field, e.g. "// Types that are valid to be assigned to MyOneof:\n\\"
}
// decl prints the declaration of the field in the struct (if any).
func (f *oneofField) decl(g *Generator, mc *msgCtx) {
comment := f.comment
for _, sf := range f.subFields {
comment += "//\t*" + sf.oneofTypeName + "\n"
}
g.P(comment, Annotate(mc.message.file, f.fullPath, f.goName), " ", f.goType, " `", f.tags, "`")
}
// getter for a oneof field will print additional discriminators and interfaces for the oneof,
// also it prints all the getters for the sub fields.
func (f *oneofField) getter(g *Generator, mc *msgCtx) {
// The discriminator type
g.P("type ", f.goType, " interface {")
g.P(f.goType, "()")
g.P("}")
g.P()
// The subField types, fulfilling the discriminator type contract
for _, sf := range f.subFields {
g.P("type ", Annotate(mc.message.file, sf.fullPath, sf.oneofTypeName), " struct {")
g.P(Annotate(mc.message.file, sf.fullPath, sf.goName), " ", sf.goType, " `", sf.tags, "`")
g.P("}")
g.P()
}
for _, sf := range f.subFields {
g.P("func (*", sf.oneofTypeName, ") ", f.goType, "() {}")
g.P()
}
// Getter for the oneof field
g.P("func (m *", mc.goName, ") ", Annotate(mc.message.file, f.fullPath, f.getterName), "() ", f.goType, " {")
g.P("if m != nil { return m.", f.goName, " }")
g.P("return nil")
g.P("}")
g.P()
// Getters for each oneof
for _, sf := range f.subFields {
if sf.deprecated != "" {
g.P(sf.deprecated)
}
g.P("func (m *", mc.goName, ") ", Annotate(mc.message.file, sf.fullPath, sf.getterName), "() "+sf.goType+" {")
g.P("if x, ok := m.", f.getterName, "().(*", sf.oneofTypeName, "); ok {")
g.P("return x.", sf.goName)
g.P("}")
g.P("return ", sf.getterDef)
g.P("}")
g.P()
}
}
// setter prints the setter method of the field.
func (f *oneofField) setter(g *Generator, mc *msgCtx) {
// No setters for oneof yet
}
// topLevelField interface implemented by all types of fields on the top level (not oneofSubField).
type topLevelField interface {
decl(g *Generator, mc *msgCtx) // print declaration within the struct
getter(g *Generator, mc *msgCtx) // print getter
setter(g *Generator, mc *msgCtx) // print setter if applicable
}
// defField interface implemented by all types of fields that can have defaults (not oneofField, but instead oneofSubField).
type defField interface {
getProtoDef() string // default value explicitly stated in the proto file, e.g "yoshi" or "5"
getProtoName() string // proto name of a field, e.g. "field_name" or "descriptor"
getGoType() string // go type of the field as a string, e.g. "*int32"
getProtoTypeName() string // protobuf type name for the field, e.g. ".google.protobuf.Duration"
getProtoType() descriptor.FieldDescriptorProto_Type // *field.Type value, e.g. descriptor.FieldDescriptorProto_TYPE_FIXED64
}
// generateDefaultConstants adds constants for default values if needed, which is only if the default value is.
// explicit in the proto.
func (g *Generator) generateDefaultConstants(mc *msgCtx, topLevelFields []topLevelField) {
// Collect fields that can have defaults
dFields := []defField{}
for _, pf := range topLevelFields {
if f, ok := pf.(*oneofField); ok {
for _, osf := range f.subFields {
dFields = append(dFields, osf)
}
continue
}
dFields = append(dFields, pf.(defField))
}
for _, df := range dFields {
def := df.getProtoDef()
if def == "" {
continue
}
fieldname := g.defaultConstantName(mc.goName, df.getProtoName())
typename := df.getGoType()
if typename[0] == '*' {
typename = typename[1:]
}
kind := "const "
switch {
case typename == "bool":
case typename == "string":
def = strconv.Quote(def)
case typename == "[]byte":
def = "[]byte(" + strconv.Quote(unescape(def)) + ")"
kind = "var "
case def == "inf", def == "-inf", def == "nan":
// These names are known to, and defined by, the protocol language.
switch def {
case "inf":
def = "math.Inf(1)"
case "-inf":
def = "math.Inf(-1)"
case "nan":
def = "math.NaN()"
}
if df.getProtoType() == descriptor.FieldDescriptorProto_TYPE_FLOAT {
def = "float32(" + def + ")"
}
kind = "var "
case df.getProtoType() == descriptor.FieldDescriptorProto_TYPE_FLOAT:
if f, err := strconv.ParseFloat(def, 32); err == nil {
def = fmt.Sprint(float32(f))
}
case df.getProtoType() == descriptor.FieldDescriptorProto_TYPE_DOUBLE:
if f, err := strconv.ParseFloat(def, 64); err == nil {
def = fmt.Sprint(f)
}
case df.getProtoType() == descriptor.FieldDescriptorProto_TYPE_ENUM:
// Must be an enum. Need to construct the prefixed name.
obj := g.ObjectNamed(df.getProtoTypeName())
var enum *EnumDescriptor
if id, ok := obj.(*ImportedDescriptor); ok {
// The enum type has been publicly imported.
enum, _ = id.o.(*EnumDescriptor)
} else {
enum, _ = obj.(*EnumDescriptor)
}
if enum == nil {
log.Printf("don't know how to generate constant for %s", fieldname)
continue
}
def = g.DefaultPackageName(obj) + enum.prefix() + def
}
g.P(kind, fieldname, " ", typename, " = ", def)
g.file.addExport(mc.message, constOrVarSymbol{fieldname, kind, ""})
}
g.P()
}
// generateInternalStructFields just adds the XXX_<something> fields to the message struct.
func (g *Generator) generateInternalStructFields(mc *msgCtx, topLevelFields []topLevelField) {
g.P("XXX_NoUnkeyedLiteral\tstruct{} `json:\"-\"`") // prevent unkeyed struct literals
if len(mc.message.ExtensionRange) > 0 {
messageset := ""
if opts := mc.message.Options; opts != nil && opts.GetMessageSetWireFormat() {
messageset = "protobuf_messageset:\"1\" "
}
g.P(g.Pkg["proto"], ".XXX_InternalExtensions `", messageset, "json:\"-\"`")
}
g.P("XXX_unrecognized\t[]byte `json:\"-\"`")
g.P("XXX_sizecache\tint32 `json:\"-\"`")
}
// generateOneofFuncs adds all the utility functions for oneof, including marshalling, unmarshalling and sizer.
func (g *Generator) generateOneofFuncs(mc *msgCtx, topLevelFields []topLevelField) {
ofields := []*oneofField{}
for _, f := range topLevelFields {
if o, ok := f.(*oneofField); ok {
ofields = append(ofields, o)
}
}
if len(ofields) == 0 {
return
}
// OneofFuncs
g.P("// XXX_OneofWrappers is for the internal use of the proto package.")
g.P("func (*", mc.goName, ") XXX_OneofWrappers() []interface{} {")
g.P("return []interface{}{")
for _, of := range ofields {
for _, sf := range of.subFields {
sf.typedNil(g)
}
}
g.P("}")
g.P("}")
g.P()
}
// generateMessageStruct adds the actual struct with it's members (but not methods) to the output.
func (g *Generator) generateMessageStruct(mc *msgCtx, topLevelFields []topLevelField) {
comments := g.PrintComments(mc.message.path)
// Guarantee deprecation comments appear after user-provided comments.
if mc.message.GetOptions().GetDeprecated() {
if comments {
// Convention: Separate deprecation comments from original
// comments with an empty line.
g.P("//")
}
g.P(deprecationComment)
}
g.P("type ", Annotate(mc.message.file, mc.message.path, mc.goName), " struct {")
for _, pf := range topLevelFields {
pf.decl(g, mc)
}
g.generateInternalStructFields(mc, topLevelFields)
g.P("}")
}
// generateGetters adds getters for all fields, including oneofs and weak fields when applicable.
func (g *Generator) generateGetters(mc *msgCtx, topLevelFields []topLevelField) {
for _, pf := range topLevelFields {
pf.getter(g, mc)
}
}
// generateSetters add setters for all fields, including oneofs and weak fields when applicable.
func (g *Generator) generateSetters(mc *msgCtx, topLevelFields []topLevelField) {
for _, pf := range topLevelFields {
pf.setter(g, mc)
}
}
// generateCommonMethods adds methods to the message that are not on a per field basis.
func (g *Generator) generateCommonMethods(mc *msgCtx) {
// Reset, String and ProtoMessage methods.
g.P("func (m *", mc.goName, ") Reset() { *m = ", mc.goName, "{} }")
g.P("func (m *", mc.goName, ") String() string { return ", g.Pkg["proto"], ".CompactTextString(m) }")
g.P("func (*", mc.goName, ") ProtoMessage() {}")
var indexes []string
for m := mc.message; m != nil; m = m.parent {
indexes = append([]string{strconv.Itoa(m.index)}, indexes...)
}
g.P("func (*", mc.goName, ") Descriptor() ([]byte, []int) {")
g.P("return ", g.file.VarName(), ", []int{", strings.Join(indexes, ", "), "}")
g.P("}")
g.P()
// TODO: Revisit the decision to use a XXX_WellKnownType method
// if we change proto.MessageName to work with multiple equivalents.
if mc.message.file.GetPackage() == "google.protobuf" && wellKnownTypes[mc.message.GetName()] {
g.P("func (*", mc.goName, `) XXX_WellKnownType() string { return "`, mc.message.GetName(), `" }`)
g.P()
}
// Extension support methods
if len(mc.message.ExtensionRange) > 0 {
g.P()
g.P("var extRange_", mc.goName, " = []", g.Pkg["proto"], ".ExtensionRange{")
for _, r := range mc.message.ExtensionRange {
end := fmt.Sprint(*r.End - 1) // make range inclusive on both ends
g.P("{Start: ", r.Start, ", End: ", end, "},")
}
g.P("}")
g.P("func (*", mc.goName, ") ExtensionRangeArray() []", g.Pkg["proto"], ".ExtensionRange {")
g.P("return extRange_", mc.goName)
g.P("}")
g.P()
}
// TODO: It does not scale to keep adding another method for every
// operation on protos that we want to switch over to using the
// table-driven approach. Instead, we should only add a single method
// that allows getting access to the *InternalMessageInfo struct and then
// calling Unmarshal, Marshal, Merge, Size, and Discard directly on that.
// Wrapper for table-driven marshaling and unmarshaling.
g.P("func (m *", mc.goName, ") XXX_Unmarshal(b []byte) error {")
g.P("return xxx_messageInfo_", mc.goName, ".Unmarshal(m, b)")
g.P("}")
g.P("func (m *", mc.goName, ") XXX_Marshal(b []byte, deterministic bool) ([]byte, error) {")
g.P("return xxx_messageInfo_", mc.goName, ".Marshal(b, m, deterministic)")
g.P("}")
g.P("func (m *", mc.goName, ") XXX_Merge(src ", g.Pkg["proto"], ".Message) {")
g.P("xxx_messageInfo_", mc.goName, ".Merge(m, src)")
g.P("}")
g.P("func (m *", mc.goName, ") XXX_Size() int {") // avoid name clash with "Size" field in some message
g.P("return xxx_messageInfo_", mc.goName, ".Size(m)")
g.P("}")
g.P("func (m *", mc.goName, ") XXX_DiscardUnknown() {")
g.P("xxx_messageInfo_", mc.goName, ".DiscardUnknown(m)")
g.P("}")
g.P("var xxx_messageInfo_", mc.goName, " ", g.Pkg["proto"], ".InternalMessageInfo")
g.P()
}
// Generate the type, methods and default constant definitions for this Descriptor.
func (g *Generator) generateMessage(message *Descriptor) {
topLevelFields := []topLevelField{}
oFields := make(map[int32]*oneofField)
// The full type name
typeName := message.TypeName()
// The full type name, CamelCased.
goTypeName := CamelCaseSlice(typeName)
usedNames := make(map[string]bool)
for _, n := range methodNames {
usedNames[n] = true
}
// allocNames finds a conflict-free variation of the given strings,
// consistently mutating their suffixes.
// It returns the same number of strings.
allocNames := func(ns ...string) []string {
Loop:
for {
for _, n := range ns {
if usedNames[n] {
for i := range ns {
ns[i] += "_"
}
continue Loop
}
}
for _, n := range ns {
usedNames[n] = true
}
return ns
}
}
mapFieldTypes := make(map[*descriptor.FieldDescriptorProto]string) // keep track of the map fields to be added later
// Build a structure more suitable for generating the text in one pass
for i, field := range message.Field {
// Allocate the getter and the field at the same time so name
// collisions create field/method consistent names.
// TODO: This allocation occurs based on the order of the fields
// in the proto file, meaning that a change in the field
// ordering can change generated Method/Field names.
base := CamelCase(*field.Name)
ns := allocNames(base, "Get"+base)
fieldName, fieldGetterName := ns[0], ns[1]
typename, wiretype := g.GoType(message, field)
jsonName := *field.Name
tag := fmt.Sprintf("protobuf:%s json:%q", g.goTag(message, field, wiretype), jsonName+",omitempty")
oneof := field.OneofIndex != nil
if oneof && oFields[*field.OneofIndex] == nil {
odp := message.OneofDecl[int(*field.OneofIndex)]
base := CamelCase(odp.GetName())
fname := allocNames(base)[0]
// This is the first field of a oneof we haven't seen before.
// Generate the union field.
oneofFullPath := fmt.Sprintf("%s,%d,%d", message.path, messageOneofPath, *field.OneofIndex)
c, ok := g.makeComments(oneofFullPath)
if ok {
c += "\n//\n"
}
c += "// Types that are valid to be assigned to " + fname + ":\n"
// Generate the rest of this comment later,
// when we've computed any disambiguation.
dname := "is" + goTypeName + "_" + fname
tag := `protobuf_oneof:"` + odp.GetName() + `"`
of := oneofField{
fieldCommon: fieldCommon{
goName: fname,
getterName: "Get"+fname,
goType: dname,
tags: tag,
protoName: odp.GetName(),
fullPath: oneofFullPath,
},
comment: c,
}
topLevelFields = append(topLevelFields, &of)
oFields[*field.OneofIndex] = &of
}
if *field.Type == descriptor.FieldDescriptorProto_TYPE_MESSAGE {
desc := g.ObjectNamed(field.GetTypeName())
if d, ok := desc.(*Descriptor); ok && d.GetOptions().GetMapEntry() {
// Figure out the Go types and tags for the key and value types.
keyField, valField := d.Field[0], d.Field[1]
keyType, keyWire := g.GoType(d, keyField)
valType, valWire := g.GoType(d, valField)
keyTag, valTag := g.goTag(d, keyField, keyWire), g.goTag(d, valField, valWire)
// We don't use stars, except for message-typed values.
// Message and enum types are the only two possibly foreign types used in maps,
// so record their use. They are not permitted as map keys.
keyType = strings.TrimPrefix(keyType, "*")
switch *valField.Type {
case descriptor.FieldDescriptorProto_TYPE_ENUM:
valType = strings.TrimPrefix(valType, "*")
g.RecordTypeUse(valField.GetTypeName())
case descriptor.FieldDescriptorProto_TYPE_MESSAGE:
g.RecordTypeUse(valField.GetTypeName())
default:
valType = strings.TrimPrefix(valType, "*")
}
typename = fmt.Sprintf("map[%s]%s", keyType, valType)
mapFieldTypes[field] = typename // record for the getter generation
tag += fmt.Sprintf(" protobuf_key:%s protobuf_val:%s", keyTag, valTag)
}
}
fieldDeprecated := ""
if field.GetOptions().GetDeprecated() {
fieldDeprecated = deprecationComment
}
dvalue := g.getterDefault(field, goTypeName)
if oneof {
tname := goTypeName + "_" + fieldName
// It is possible for this to collide with a message or enum
// nested in this message. Check for collisions.
for {
ok := true
for _, desc := range message.nested {
if CamelCaseSlice(desc.TypeName()) == tname {
ok = false
break
}
}
for _, enum := range message.enums {
if CamelCaseSlice(enum.TypeName()) == tname {
ok = false
break
}
}
if !ok {
tname += "_"
continue
}
break
}
oneofField := oFields[*field.OneofIndex]
tag := "protobuf:" + g.goTag(message, field, wiretype)
sf := oneofSubField{
fieldCommon: fieldCommon{
goName: fieldName,
getterName: fieldGetterName,
goType: typename,
tags: tag,
protoName: field.GetName(),
fullPath: fmt.Sprintf("%s,%d,%d", message.path, messageFieldPath, i),
},
protoTypeName: field.GetTypeName(),
fieldNumber: int(*field.Number),
protoType: *field.Type,
getterDef: dvalue,
protoDef: field.GetDefaultValue(),
oneofTypeName: tname,
deprecated: fieldDeprecated,
}
oneofField.subFields = append(oneofField.subFields, &sf)
g.RecordTypeUse(field.GetTypeName())
continue
}
fieldFullPath := fmt.Sprintf("%s,%d,%d", message.path, messageFieldPath, i)
c, ok := g.makeComments(fieldFullPath)
if ok {
c += "\n"
}
rf := simpleField{
fieldCommon: fieldCommon{
goName: fieldName,
getterName: fieldGetterName,
goType: typename,
tags: tag,
protoName: field.GetName(),
fullPath: fieldFullPath,
},
protoTypeName: field.GetTypeName(),
protoType: *field.Type,
deprecated: fieldDeprecated,
getterDef: dvalue,
protoDef: field.GetDefaultValue(),
comment: c,
}
var pf topLevelField = &rf
topLevelFields = append(topLevelFields, pf)
g.RecordTypeUse(field.GetTypeName())
}
mc := &msgCtx{
goName: goTypeName,
message: message,
}
g.generateMessageStruct(mc, topLevelFields)
g.P()
g.generateCommonMethods(mc)
g.P()
g.generateDefaultConstants(mc, topLevelFields)
g.P()
g.generateGetters(mc, topLevelFields)
g.P()
g.generateSetters(mc, topLevelFields)
g.P()
g.generateOneofFuncs(mc, topLevelFields)
g.P()
var oneofTypes []string
for _, f := range topLevelFields {
if of, ok := f.(*oneofField); ok {
for _, osf := range of.subFields {
oneofTypes = append(oneofTypes, osf.oneofTypeName)
}
}
}
opts := message.Options
ms := &messageSymbol{
sym: goTypeName,
hasExtensions: len(message.ExtensionRange) > 0,
isMessageSet: opts != nil && opts.GetMessageSetWireFormat(),
oneofTypes: oneofTypes,
}
g.file.addExport(message, ms)
for _, ext := range message.ext {
g.generateExtension(ext)
}
fullName := strings.Join(message.TypeName(), ".")
if g.file.Package != nil {
fullName = *g.file.Package + "." + fullName
}
g.addInitf("%s.RegisterType((*%s)(nil), %q)", g.Pkg["proto"], goTypeName, fullName)
// Register types for native map types.
for _, k := range mapFieldKeys(mapFieldTypes) {
fullName := strings.TrimPrefix(*k.TypeName, ".")
g.addInitf("%s.RegisterMapType((%s)(nil), %q)", g.Pkg["proto"], mapFieldTypes[k], fullName)
}
}
type byTypeName []*descriptor.FieldDescriptorProto
func (a byTypeName) Len() int { return len(a) }
func (a byTypeName) Swap(i, j int) { a[i], a[j] = a[j], a[i] }
func (a byTypeName) Less(i, j int) bool { return *a[i].TypeName < *a[j].TypeName }
// mapFieldKeys returns the keys of m in a consistent order.
func mapFieldKeys(m map[*descriptor.FieldDescriptorProto]string) []*descriptor.FieldDescriptorProto {
keys := make([]*descriptor.FieldDescriptorProto, 0, len(m))
for k := range m {
keys = append(keys, k)
}
sort.Sort(byTypeName(keys))
return keys
}
var escapeChars = [256]byte{
'a': '\a', 'b': '\b', 'f': '\f', 'n': '\n', 'r': '\r', 't': '\t', 'v': '\v', '\\': '\\', '"': '"', '\'': '\'', '?': '?',
}
// unescape reverses the "C" escaping that protoc does for default values of bytes fields.
// It is best effort in that it effectively ignores malformed input. Seemingly invalid escape
// sequences are conveyed, unmodified, into the decoded result.
func unescape(s string) string {
// NB: Sadly, we can't use strconv.Unquote because protoc will escape both
// single and double quotes, but strconv.Unquote only allows one or the
// other (based on actual surrounding quotes of its input argument).
var out []byte
for len(s) > 0 {
// regular character, or too short to be valid escape
if s[0] != '\\' || len(s) < 2 {
out = append(out, s[0])
s = s[1:]
} else if c := escapeChars[s[1]]; c != 0 {
// escape sequence
out = append(out, c)
s = s[2:]
} else if s[1] == 'x' || s[1] == 'X' {
// hex escape, e.g. "\x80
if len(s) < 4 {
// too short to be valid
out = append(out, s[:2]...)
s = s[2:]
continue
}
v, err := strconv.ParseUint(s[2:4], 16, 8)
if err != nil {
out = append(out, s[:4]...)
} else {
out = append(out, byte(v))
}
s = s[4:]
} else if '0' <= s[1] && s[1] <= '7' {
// octal escape, can vary from 1 to 3 octal digits; e.g., "\0" "\40" or "\164"
// so consume up to 2 more bytes or up to end-of-string
n := len(s[1:]) - len(strings.TrimLeft(s[1:], "01234567"))
if n > 3 {
n = 3
}
v, err := strconv.ParseUint(s[1:1+n], 8, 8)
if err != nil {
out = append(out, s[:1+n]...)
} else {
out = append(out, byte(v))
}
s = s[1+n:]
} else {
// bad escape, just propagate the slash as-is
out = append(out, s[0])
s = s[1:]
}
}
return string(out)
}
func (g *Generator) generateExtension(ext *ExtensionDescriptor) {
ccTypeName := ext.DescName()
extObj := g.ObjectNamed(*ext.Extendee)
var extDesc *Descriptor
if id, ok := extObj.(*ImportedDescriptor); ok {
// This is extending a publicly imported message.
// We need the underlying type for goTag.
extDesc = id.o.(*Descriptor)
} else {
extDesc = extObj.(*Descriptor)
}
extendedType := "*" + g.TypeName(extObj) // always use the original
field := ext.FieldDescriptorProto
fieldType, wireType := g.GoType(ext.parent, field)
tag := g.goTag(extDesc, field, wireType)
g.RecordTypeUse(*ext.Extendee)
if n := ext.FieldDescriptorProto.TypeName; n != nil {
// foreign extension type
g.RecordTypeUse(*n)
}
typeName := ext.TypeName()
// Special case for proto2 message sets: If this extension is extending
// proto2.bridge.MessageSet, and its final name component is "message_set_extension",
// then drop that last component.
//
// TODO: This should be implemented in the text formatter rather than the generator.
// In addition, the situation for when to apply this special case is implemented
// differently in other languages:
// https://github.com/google/protobuf/blob/aff10976/src/google/protobuf/text_format.cc#L1560
if extDesc.GetOptions().GetMessageSetWireFormat() && typeName[len(typeName)-1] == "message_set_extension" {
typeName = typeName[:len(typeName)-1]
}
// For text formatting, the package must be exactly what the .proto file declares,
// ignoring overrides such as the go_package option, and with no dot/underscore mapping.
extName := strings.Join(typeName, ".")
if g.file.Package != nil {
extName = *g.file.Package + "." + extName
}
g.P("var ", ccTypeName, " = &", g.Pkg["proto"], ".ExtensionDesc{")
g.P("ExtendedType: (", extendedType, ")(nil),")
g.P("ExtensionType: (", fieldType, ")(nil),")
g.P("Field: ", field.Number, ",")
g.P(`Name: "`, extName, `",`)
g.P("Tag: ", tag, ",")
g.P(`Filename: "`, g.file.GetName(), `",`)
g.P("}")
g.P()
g.addInitf("%s.RegisterExtension(%s)", g.Pkg["proto"], ext.DescName())
g.file.addExport(ext, constOrVarSymbol{ccTypeName, "var", ""})
}
func (g *Generator) generateInitFunction() {
if len(g.init) == 0 {
return
}
g.P("func init() {")
for _, l := range g.init {
g.P(l)
}
g.P("}")
g.init = nil
}
func (g *Generator) generateFileDescriptor(file *FileDescriptor) {
// Make a copy and trim source_code_info data.
// TODO: Trim this more when we know exactly what we need.
pb := proto.Clone(file.FileDescriptorProto).(*descriptor.FileDescriptorProto)
pb.SourceCodeInfo = nil
b, err := proto.Marshal(pb)
if err != nil {
g.Fail(err.Error())
}
var buf bytes.Buffer
w, _ := gzip.NewWriterLevel(&buf, gzip.BestCompression)
w.Write(b)
w.Close()
b = buf.Bytes()
v := file.VarName()
g.P()
g.P("func init() { ", g.Pkg["proto"], ".RegisterFile(", strconv.Quote(*file.Name), ", ", v, ") }")
g.P("var ", v, " = []byte{")
g.P("// ", len(b), " bytes of a gzipped FileDescriptorProto")
for len(b) > 0 {
n := 16
if n > len(b) {
n = len(b)
}
s := ""
for _, c := range b[:n] {
s += fmt.Sprintf("0x%02x,", c)
}
g.P(s)
b = b[n:]
}
g.P("}")
}
func (g *Generator) generateEnumRegistration(enum *EnumDescriptor) {
// // We always print the full (proto-world) package name here.
pkg := enum.File().GetPackage()
if pkg != "" {
pkg += "."
}
// The full type name
typeName := enum.TypeName()
// The full type name, CamelCased.
ccTypeName := CamelCaseSlice(typeName)
g.addInitf("%s.RegisterEnum(%q, %[3]s_name, %[3]s_value)", g.Pkg["proto"], pkg+ccTypeName, ccTypeName)
}
// And now lots of helper functions.
// Is c an ASCII lower-case letter?
func isASCIILower(c byte) bool {
return 'a' <= c && c <= 'z'
}
// Is c an ASCII digit?
func isASCIIDigit(c byte) bool {
return '0' <= c && c <= '9'
}
// CamelCase returns the CamelCased name.
// If there is an interior underscore followed by a lower case letter,
// drop the underscore and convert the letter to upper case.
// There is a remote possibility of this rewrite causing a name collision,
// but it's so remote we're prepared to pretend it's nonexistent - since the
// C++ generator lowercases names, it's extremely unlikely to have two fields
// with different capitalizations.
// In short, _my_field_name_2 becomes XMyFieldName_2.
func CamelCase(s string) string {
if s == "" {
return ""
}
t := make([]byte, 0, 32)
i := 0
if s[0] == '_' {
// Need a capital letter; drop the '_'.
t = append(t, 'X')
i++
}
// Invariant: if the next letter is lower case, it must be converted
// to upper case.
// That is, we process a word at a time, where words are marked by _ or
// upper case letter. Digits are treated as words.
for ; i < len(s); i++ {
c := s[i]
if c == '_' && i+1 < len(s) && isASCIILower(s[i+1]) {
continue // Skip the underscore in s.
}
if isASCIIDigit(c) {
t = append(t, c)
continue
}
// Assume we have a letter now - if not, it's a bogus identifier.
// The next word is a sequence of characters that must start upper case.
if isASCIILower(c) {
c ^= ' ' // Make it a capital letter.
}
t = append(t, c) // Guaranteed not lower case.
// Accept lower case sequence that follows.
for i+1 < len(s) && isASCIILower(s[i+1]) {
i++
t = append(t, s[i])
}
}
return string(t)
}
// CamelCaseSlice is like CamelCase, but the argument is a slice of strings to
// be joined with "_".
func CamelCaseSlice(elem []string) string { return CamelCase(strings.Join(elem, "_")) }
// dottedSlice turns a sliced name into a dotted name.
func dottedSlice(elem []string) string { return strings.Join(elem, ".") }
// Is this field optional?
func isOptional(field *descriptor.FieldDescriptorProto) bool {
return field.Label != nil && *field.Label == descriptor.FieldDescriptorProto_LABEL_OPTIONAL
}
// Is this field required?
func isRequired(field *descriptor.FieldDescriptorProto) bool {
return field.Label != nil && *field.Label == descriptor.FieldDescriptorProto_LABEL_REQUIRED
}
// Is this field repeated?
func isRepeated(field *descriptor.FieldDescriptorProto) bool {
return field.Label != nil && *field.Label == descriptor.FieldDescriptorProto_LABEL_REPEATED
}
// Is this field a scalar numeric type?
func isScalar(field *descriptor.FieldDescriptorProto) bool {
if field.Type == nil {
return false
}
switch *field.Type {
case descriptor.FieldDescriptorProto_TYPE_DOUBLE,
descriptor.FieldDescriptorProto_TYPE_FLOAT,
descriptor.FieldDescriptorProto_TYPE_INT64,
descriptor.FieldDescriptorProto_TYPE_UINT64,
descriptor.FieldDescriptorProto_TYPE_INT32,
descriptor.FieldDescriptorProto_TYPE_FIXED64,
descriptor.FieldDescriptorProto_TYPE_FIXED32,
descriptor.FieldDescriptorProto_TYPE_BOOL,
descriptor.FieldDescriptorProto_TYPE_UINT32,
descriptor.FieldDescriptorProto_TYPE_ENUM,
descriptor.FieldDescriptorProto_TYPE_SFIXED32,
descriptor.FieldDescriptorProto_TYPE_SFIXED64,
descriptor.FieldDescriptorProto_TYPE_SINT32,
descriptor.FieldDescriptorProto_TYPE_SINT64:
return true
default:
return false
}
}
// badToUnderscore is the mapping function used to generate Go names from package names,
// which can be dotted in the input .proto file. It replaces non-identifier characters such as
// dot or dash with underscore.
func badToUnderscore(r rune) rune {
if unicode.IsLetter(r) || unicode.IsDigit(r) || r == '_' {
return r
}
return '_'
}
// baseName returns the last path element of the name, with the last dotted suffix removed.
func baseName(name string) string {
// First, find the last element
if i := strings.LastIndex(name, "/"); i >= 0 {
name = name[i+1:]
}
// Now drop the suffix
if i := strings.LastIndex(name, "."); i >= 0 {
name = name[0:i]
}
return name
}
// The SourceCodeInfo message describes the location of elements of a parsed
// .proto file by way of a "path", which is a sequence of integers that
// describe the route from a FileDescriptorProto to the relevant submessage.
// The path alternates between a field number of a repeated field, and an index
// into that repeated field. The constants below define the field numbers that
// are used.
//
// See descriptor.proto for more information about this.
const (
// tag numbers in FileDescriptorProto
packagePath = 2 // package
messagePath = 4 // message_type
enumPath = 5 // enum_type
// tag numbers in DescriptorProto
messageFieldPath = 2 // field
messageMessagePath = 3 // nested_type
messageEnumPath = 4 // enum_type
messageOneofPath = 8 // oneof_decl
// tag numbers in EnumDescriptorProto
enumValuePath = 2 // value
)
var supportTypeAliases bool
func init() {
for _, tag := range build.Default.ReleaseTags {
if tag == "go1.9" {
supportTypeAliases = true
return
}
}
}