Pass name attr directly rather than via kwargs
Version 3.0.0 has been released with updated Protobuf and gRPC versions and a number of major improvements. For some languages this may not be a drop-in replacement and it may be necessary to update your WORKSPACE file due to changes in dependencies; please see the above linked release notes for details or the language specific rules pages. If you discover any problems with the new release, please open a new issue, create a discussion or otherwise check in the #proto channel on Bazel Slack.
Version 4.0 of Bazel has been released recently and is supported without update for most languages. Changes for full Bazel 4.0 compatibility and updated dependencies are in progress.
These rules provide Protocol Buffers (Protobuf) and gRPC rules for a range of languages and services.
Each supported language ({lang} below) is generally split into four rule flavours:
{lang}_proto_compile: Provides generated files from the Protobuf protoc plugin for the language. e.g for C++ this provides the generated *.pb.cc and *.pb.h files.
{lang}_proto_library: Provides a language-specific library from the generated Protobuf protoc plugin outputs, along with necessary dependencies. e.g for C++ this provides a Bazel native cpp_library created from the generated *.pb.cc and *pb.h files, with the Protobuf library linked. For languages that do not have a ‘library’ concept, this rule may not exist.
{lang}_grpc_compile: Provides generated files from both the Protobuf and gRPC protoc plugins for the language. e.g for C++ this provides the generated *.pb.cc, *.grpc.pb.cc, *.pb.h and *.grpc.pb.h files.
{lang}_grpc_library: Provides a language-specific library from the generated Protobuf and gRPC protoc plugins outputs, along with necessary dependencies. e.g for C++ this provides a Bazel native cpp_library created from the generated *.pb.cc, *.grpc.pb.cc, *.pb.h and *.grpc.pb.h files, with the Protobuf and gRPC libraries linked. For languages that do not have a ‘library’ concept, this rule may not exist.
Therefore, if you are solely interested in the generated source code artifacts, use the {lang}_{proto|grpc}_compile rules. Otherwise, if you want a ready-to-go library, use the {lang}_{proto|grpc}_library rules.
Add rules_proto_grpc to your WORKSPACE file and then look at the language specific examples linked below:
load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive") http_archive( name = "rules_proto_grpc", urls = ["https://github.com/rules-proto-grpc/rules_proto_grpc/archive/2.0.0.tar.gz"], sha256 = "d771584bbff98698e7cb3cb31c132ee206a972569f4dc8b65acbdd934d156b33", strip_prefix = "rules_proto_grpc-2.0.0", ) load("@rules_proto_grpc//:repositories.bzl", "rules_proto_grpc_toolchains", "rules_proto_grpc_repos") rules_proto_grpc_toolchains() rules_proto_grpc_repos() load("@rules_proto//proto:repositories.bzl", "rules_proto_dependencies", "rules_proto_toolchains") rules_proto_dependencies() rules_proto_toolchains()
It is recommended that you use the tagged releases for stable rules. Master is intended to be ‘ready-to-use’, but may be unstable at certain periods. To be notified of new releases, you can use GitHub's ‘Watch Releases Only’ on the repository.
Important: You will also need to follow instructions in the language-specific
README.mdfor additional workspace dependencies that may be required.
| Language | Rule | Description |
|---|---|---|
| Android | android_proto_compile | Generates an Android protobuf .jar artifact (example) |
| Android | android_grpc_compile | Generates Android protobuf+gRPC .jar artifacts (example) |
| Android | android_proto_library | Generates an Android protobuf library using android_library from rules_android (example) |
| Android | android_grpc_library | Generates Android protobuf+gRPC library using android_library from rules_android (example) |
| C | c_proto_compile | Generates C protobuf .h & .c artifacts (example) |
| C | c_proto_library | Generates a C protobuf library using cc_library, with dependencies linked (example) |
| C++ | cpp_proto_compile | Generates C++ protobuf .h & .cc artifacts (example) |
| C++ | cpp_grpc_compile | Generates C++ protobuf+gRPC .h & .cc artifacts (example) |
| C++ | cpp_proto_library | Generates a C++ protobuf library using cc_library, with dependencies linked (example) |
| C++ | cpp_grpc_library | Generates a C++ protobuf+gRPC library using cc_library, with dependencies linked (example) |
| C# | csharp_proto_compile | Generates C# protobuf .cs artifacts (example) |
| C# | csharp_grpc_compile | Generates C# protobuf+gRPC .cs artifacts (example) |
| C# | csharp_proto_library | Generates a C# protobuf library using core_library from rules_dotnet. Note that the library name must end in .dll (example) |
| C# | csharp_grpc_library | Generates a C# protobuf+gRPC library using core_library from rules_dotnet. Note that the library name must end in .dll (example) |
| D | d_proto_compile | Generates D protobuf .d artifacts (example) |
| D | d_proto_library | Generates a D protobuf library using d_library from rules_d (example) |
| Go | go_proto_compile | Generates Go protobuf .go artifacts (example) |
| Go | go_grpc_compile | Generates Go protobuf+gRPC .go artifacts (example) |
| Go | go_proto_library | Generates a Go protobuf library using go_library from rules_go (example) |
| Go | go_grpc_library | Generates a Go protobuf+gRPC library using go_library from rules_go (example) |
| grpc-gateway | gateway_grpc_compile | Generates grpc-gateway .go files (example) |
| grpc-gateway | gateway_openapiv2_compile | Generates grpc-gateway OpenAPI v2 .json files (example) |
| grpc-gateway | gateway_grpc_library | Generates grpc-gateway library files (example) |
| Java | java_proto_compile | Generates a Java protobuf srcjar artifact (example) |
| Java | java_grpc_compile | Generates a Java protobuf+gRPC srcjar artifact (example) |
| Java | java_proto_library | Generates a Java protobuf library using java_library (example) |
| Java | java_grpc_library | Generates a Java protobuf+gRPC library using java_library (example) |
| JavaScript | js_proto_compile | Generates JavaScript protobuf .js and .d.ts artifacts (example) |
| JavaScript | js_grpc_node_compile | Generates JavaScript protobuf + gRPC-node .js and .d.ts artifacts (example) |
| JavaScript | js_grpc_web_compile | Generates JavaScript protobuf + gRPC-Web .js and .d.ts artifacts (example) |
| JavaScript | js_proto_library | Generates a JavaScript protobuf library using js_library from rules_nodejs (example) |
| JavaScript | js_grpc_node_library | Generates a Node.js protobuf + gRPC-node library using js_library from rules_nodejs (example) |
| JavaScript | js_grpc_web_library | Generates a JavaScript protobuf + gRPC-Web library using js_library from rules_nodejs (example) |
| Objective-C | objc_proto_compile | Generates Objective-C protobuf .m & .h artifacts (example) |
| Objective-C | objc_grpc_compile | Generates Objective-C protobuf+gRPC .m & .h artifacts (example) |
| Objective-C | objc_proto_library | Generates an Objective-C protobuf library using objc_library (example) |
| PHP | php_proto_compile | Generates PHP protobuf .php artifacts (example) |
| PHP | php_grpc_compile | Generates PHP protobuf+gRPC .php artifacts (example) |
| Python | python_proto_compile | Generates Python protobuf .py artifacts (example) |
| Python | python_grpc_compile | Generates Python protobuf+gRPC .py artifacts (example) |
| Python | python_grpclib_compile | Generates Python protobuf+grpclib .py artifacts (supports Python 3 only) (example) |
| Python | python_proto_library | Generates a Python protobuf library using py_library from rules_python (example) |
| Python | python_grpc_library | Generates a Python protobuf+gRPC library using py_library from rules_python (example) |
| Python | python_grpclib_library | Generates a Python protobuf+grpclib library using py_library from rules_python (supports Python 3 only) (example) |
| Ruby | ruby_proto_compile | Generates Ruby protobuf .rb artifacts (example) |
| Ruby | ruby_grpc_compile | Generates Ruby protobuf+gRPC .rb artifacts (example) |
| Ruby | ruby_proto_library | Generates a Ruby protobuf library using ruby_library from rules_ruby (example) |
| Ruby | ruby_grpc_library | Generates a Ruby protobuf+gRPC library using ruby_library from rules_ruby (example) |
| Rust | rust_proto_compile | Generates Rust protobuf .rs artifacts (example) |
| Rust | rust_grpc_compile | Generates Rust protobuf+gRPC .rs artifacts (example) |
| Rust | rust_proto_library | Generates a Rust protobuf library using rust_library from rules_rust (example) |
| Rust | rust_grpc_library | Generates a Rust protobuf+gRPC library using rust_library from rules_rust (example) |
| Scala | scala_proto_compile | Generates a Scala protobuf .jar artifact (example) |
| Scala | scala_grpc_compile | Generates Scala protobuf+gRPC .jar artifacts (example) |
| Scala | scala_proto_library | Generates a Scala protobuf library using scala_library from rules_scala (example) |
| Scala | scala_grpc_library | Generates a Scala protobuf+gRPC library using scala_library from rules_scala (example) |
| Swift | swift_proto_compile | Generates Swift protobuf .swift artifacts (example) |
| Swift | swift_grpc_compile | Generates Swift protobuf+gRPC .swift artifacts (example) |
| Swift | swift_proto_library | Generates a Swift protobuf library using swift_library from rules_swift (example) |
| Swift | swift_grpc_library | Generates a Swift protobuf+gRPC library using swift_library from rules_swift (example) |
These steps walk through the actions required to go from a raw .proto file to a C++ library. Other languages will have a similar high-level layout.
Step 1: Write a Protocol Buffer .proto file (example: thing.proto):
syntax = "proto3"; package example; import "google/protobuf/any.proto"; message Thing { string name = 1; google.protobuf.Any payload = 2; }
Step 2: Write a BAZEL.build file with a proto_library target:
proto_library( name = "thing_proto", srcs = ["thing.proto"], deps = ["@com_google_protobuf//:any_proto"], )
In this example we have a dependency on a well-known type any.proto, hence the proto_library to proto_library dependency ("@com_google_protobuf//:any_proto")
Step 3: Add a cpp_proto_compile target
NOTE: In this example
thing.protodoes not include service definitions (gRPC). For protos with services, use thecpp_grpc_compilerule instead.
# BUILD.bazel load("@rules_proto_grpc//cpp:defs.bzl", "cpp_proto_compile") cpp_proto_compile( name = "cpp_thing_proto", protos = [":thing_proto"], )
But wait, before we can build this, we need to load the dependencies necessary for this rule (see cpp/README.md):
Step 4: Load the workspace macro corresponding to the build rule.
# WORKSPACE load("@rules_proto_grpc//cpp:repositories.bzl", "cpp_repos") cpp_repos()
We're now ready to build the target:
Step 5: Build it!
$ bazel build //example/proto:cpp_thing_proto Target //example/proto:cpp_thing_proto up-to-date: bazel-genfiles/example/proto/cpp_thing_proto/example/proto/thing.pb.h bazel-genfiles/example/proto/cpp_thing_proto/example/proto/thing.pb.cc
If we were only interested in the generated file artifacts, the cpp_grpc_compile rule would be fine. However, for convenience we‘d rather have the outputs compiled into a C++ library. To do that, let’s change the rule from cpp_proto_compile to cpp_proto_library:
# BUILD.bazel load("@rules_proto_grpc//cpp:defs.bzl", "cpp_proto_library") cpp_proto_library( name = "cpp_thing_proto", protos = [":thing_proto"], )
$ bazel build //example/proto:cpp_thing_proto Target //example/proto:cpp_thing_proto up-to-date: bazel-bin/example/proto/libcpp_thing_proto.a bazel-bin/example/proto/libcpp_thing_proto.so bazel-genfiles/example/proto/cpp_thing_proto/example/proto/thing.pb.h bazel-genfiles/example/proto/cpp_thing_proto/example/proto/thing.pb.cc
This way, we can use //example/proto:cpp_thing_proto as a dependency of any other cc_library or cc_binary target as per normal.
NOTE: The
cpp_proto_librarytarget implicitly callscpp_proto_compile, and we can access that rule's by adding_pbat the end of the target name, likebazel build //example/proto:cpp_thing_proto_pb
Each language {lang} has a top-level subdirectory that contains:
{lang}/README.md: Generated documentation for the language rules
{lang}/repositories.bzl: Macro functions that declare repository rule dependencies for that language
{lang}/{rule}.bzl: Rule implementations of the form {lang}_{kind}_{type}, where kind is one of proto|grpc and type is one of compile|library
{lang}/BUILD.bazel: proto_plugin() declarations for the available plugins for the language
example/{lang}/{rule}/: Generated WORKSPACE and BUILD.bazel demonstrating standalone usage of the rules
{lang}/example/routeguide/: Example routeguide example implementation, if possible
To help maintain consistency of the rule implementations and documentation, all of the rule implementations are generated by the tool //tools/rulegen. Changes in the main README.md should be placed in tools/rulegen/README.header.md or tools/rulegen/README.footer.md. Changes to generated rules should be put in the source files (example: tools/rulegen/java.go).
Generally, follow the pattern seen in the multiple language examples in this repository. The basic idea is:
load("@rules_proto_grpc//:defs.bzl", "proto_plugin")name, options (not mandatory), tool and outputs. tool is a label that refers to the binary executable for the plugin itselfoutputs: A list of strings patterns that predicts the pattern of files generated by the plugin. For plugins that produce one output file per input proto fileout: The name of a single output file generated by the pluginoutput_directory: Set to true if your plugin generates files in a non-predictable way. e.g. if the output paths depend on the service names within the filesload("@rules_proto//proto:defs.bzl", "ProtoInfo") load( "@rules_proto_grpc//:defs.bzl", "ProtoLibraryAspectNodeInfo", "ProtoPluginInfo", "proto_compile_aspect_attrs", "proto_compile_aspect_impl", "proto_compile_attrs", "proto_compile_impl", ) # Create aspect example_aspect = aspect( implementation = proto_compile_aspect_impl, provides = [ProtoLibraryAspectNodeInfo], attr_aspects = ["deps"], attrs = dict( proto_compile_aspect_attrs, _plugins = attr.label_list( doc = "List of protoc plugins to apply", providers = [ProtoPluginInfo], default = [ Label("//<LABEL OF YOUR PLUGIN>"), ], ), _prefix = attr.string( doc = "String used to disambiguate aspects when generating outputs", default = "example_aspect", ), ), toolchains = ["@rules_proto_grpc//protobuf:toolchain_type"], ) # Create compile rule to apply aspect _rule = rule( implementation = proto_compile_impl, attrs = dict( proto_compile_attrs, protos = attr.label_list( mandatory = False, # TODO: set to true in 4.0.0 when deps removed below providers = [ProtoInfo], doc = "List of labels that provide a ProtoInfo (such as rules_proto proto_library)", ), deps = attr.label_list( mandatory = False, providers = [ProtoInfo, ProtoLibraryAspectNodeInfo], aspects = [example_aspect], doc = "DEPRECATED: Use protos attr", ), _plugins = attr.label_list( doc = "List of protoc plugins to apply", providers = [ProtoPluginInfo], default = [ Label("//<LABEL OF YOUR PLUGIN>"), ], ), ), toolchains = [str(Label("//protobuf:toolchain_type"))], ) # Create macro for converting attrs and passing to compile def example_compile(**kwargs): _rule( verbose_string = "{}".format(kwargs.get("verbose", 0)), **kwargs )
This project is derived from stackb/rules_proto under the Apache 2.0 license and this project therefore maintains the terms of that license
Contributions are very welcome. Please see CONTRIBUTING.md for further details.