1// Protocol Buffers - Google's data interchange format
2// Copyright 2008 Google Inc.  All rights reserved.
3// https://developers.google.com/protocol-buffers/
4//
5// Redistribution and use in source and binary forms, with or without
6// modification, are permitted provided that the following conditions are
7// met:
8//
9//     * Redistributions of source code must retain the above copyright
10// notice, this list of conditions and the following disclaimer.
11//     * Redistributions in binary form must reproduce the above
12// copyright notice, this list of conditions and the following disclaimer
13// in the documentation and/or other materials provided with the
14// distribution.
15//     * Neither the name of Google Inc. nor the names of its
16// contributors may be used to endorse or promote products derived from
17// this software without specific prior written permission.
18//
19// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30
31// Author: kenton@google.com (Kenton Varda)
32//
33// WARNING:  The plugin interface is currently EXPERIMENTAL and is subject to
34//   change.
35//
36// protoc (aka the Protocol Compiler) can be extended via plugins.  A plugin is
37// just a program that reads a CodeGeneratorRequest from stdin and writes a
38// CodeGeneratorResponse to stdout.
39//
40// Plugins written using C++ can use google/protobuf/compiler/plugin.h instead
41// of dealing with the raw protocol defined here.
42//
43// A plugin executable needs only to be placed somewhere in the path.  The
44// plugin should be named "protoc-gen-$NAME", and will then be used when the
45// flag "--${NAME}_out" is passed to protoc.
46
47syntax = "proto2";
48package google.protobuf.compiler;
49option java_package = "com.google.protobuf.compiler";
50option java_outer_classname = "PluginProtos";
51
52option go_package = "github.com/golang/protobuf/protoc-gen-go/plugin;plugin_go";
53
54import "google/protobuf/descriptor.proto";
55
56// The version number of protocol compiler.
57message Version {
58  optional int32 major = 1;
59  optional int32 minor = 2;
60  optional int32 patch = 3;
61  // A suffix for alpha, beta or rc release, e.g., "alpha-1", "rc2". It should
62  // be empty for mainline stable releases.
63  optional string suffix = 4;
64}
65
66// An encoded CodeGeneratorRequest is written to the plugin's stdin.
67message CodeGeneratorRequest {
68  // The .proto files that were explicitly listed on the command-line.  The
69  // code generator should generate code only for these files.  Each file's
70  // descriptor will be included in proto_file, below.
71  repeated string file_to_generate = 1;
72
73  // The generator parameter passed on the command-line.
74  optional string parameter = 2;
75
76  // FileDescriptorProtos for all files in files_to_generate and everything
77  // they import.  The files will appear in topological order, so each file
78  // appears before any file that imports it.
79  //
80  // protoc guarantees that all proto_files will be written after
81  // the fields above, even though this is not technically guaranteed by the
82  // protobuf wire format.  This theoretically could allow a plugin to stream
83  // in the FileDescriptorProtos and handle them one by one rather than read
84  // the entire set into memory at once.  However, as of this writing, this
85  // is not similarly optimized on protoc's end -- it will store all fields in
86  // memory at once before sending them to the plugin.
87  //
88  // Type names of fields and extensions in the FileDescriptorProto are always
89  // fully qualified.
90  repeated FileDescriptorProto proto_file = 15;
91
92  // The version number of protocol compiler.
93  optional Version compiler_version = 3;
94
95}
96
97// The plugin writes an encoded CodeGeneratorResponse to stdout.
98message CodeGeneratorResponse {
99  // Error message.  If non-empty, code generation failed.  The plugin process
100  // should exit with status code zero even if it reports an error in this way.
101  //
102  // This should be used to indicate errors in .proto files which prevent the
103  // code generator from generating correct code.  Errors which indicate a
104  // problem in protoc itself -- such as the input CodeGeneratorRequest being
105  // unparseable -- should be reported by writing a message to stderr and
106  // exiting with a non-zero status code.
107  optional string error = 1;
108
109  // Represents a single generated file.
110  message File {
111    // The file name, relative to the output directory.  The name must not
112    // contain "." or ".." components and must be relative, not be absolute (so,
113    // the file cannot lie outside the output directory).  "/" must be used as
114    // the path separator, not "\".
115    //
116    // If the name is omitted, the content will be appended to the previous
117    // file.  This allows the generator to break large files into small chunks,
118    // and allows the generated text to be streamed back to protoc so that large
119    // files need not reside completely in memory at one time.  Note that as of
120    // this writing protoc does not optimize for this -- it will read the entire
121    // CodeGeneratorResponse before writing files to disk.
122    optional string name = 1;
123
124    // If non-empty, indicates that the named file should already exist, and the
125    // content here is to be inserted into that file at a defined insertion
126    // point.  This feature allows a code generator to extend the output
127    // produced by another code generator.  The original generator may provide
128    // insertion points by placing special annotations in the file that look
129    // like:
130    //   @@protoc_insertion_point(NAME)
131    // The annotation can have arbitrary text before and after it on the line,
132    // which allows it to be placed in a comment.  NAME should be replaced with
133    // an identifier naming the point -- this is what other generators will use
134    // as the insertion_point.  Code inserted at this point will be placed
135    // immediately above the line containing the insertion point (thus multiple
136    // insertions to the same point will come out in the order they were added).
137    // The double-@ is intended to make it unlikely that the generated code
138    // could contain things that look like insertion points by accident.
139    //
140    // For example, the C++ code generator places the following line in the
141    // .pb.h files that it generates:
142    //   // @@protoc_insertion_point(namespace_scope)
143    // This line appears within the scope of the file's package namespace, but
144    // outside of any particular class.  Another plugin can then specify the
145    // insertion_point "namespace_scope" to generate additional classes or
146    // other declarations that should be placed in this scope.
147    //
148    // Note that if the line containing the insertion point begins with
149    // whitespace, the same whitespace will be added to every line of the
150    // inserted text.  This is useful for languages like Python, where
151    // indentation matters.  In these languages, the insertion point comment
152    // should be indented the same amount as any inserted code will need to be
153    // in order to work correctly in that context.
154    //
155    // The code generator that generates the initial file and the one which
156    // inserts into it must both run as part of a single invocation of protoc.
157    // Code generators are executed in the order in which they appear on the
158    // command line.
159    //
160    // If |insertion_point| is present, |name| must also be present.
161    optional string insertion_point = 2;
162
163    // The file contents.
164    optional string content = 15;
165  }
166  repeated File file = 15;
167}
168