f1c23cb216
The ultimate effect of this change will be that both the native flags and Starlark flags will continue to work with future versions of Bazel that lack the proto fragment, until such time as we deprecate or remove the flags in a Protobuf release. This decouples Bazel releases from Protobuf behavior changes. 1. Builds on the Bazel 8-compatible abstraction layer we submitted in cl/955468205 by setting `HAS_NATIVE_PROTO_FLAGS` properly in Bazel. We do this by adding a `rules.has_proto_fragment` setting to the `proto_bazel_features.bzl` mechanism: we know that the fragment no longer needs to be read in Bazel 9+, because we can use `flag_alias()` instead. 2. Adds `flag_alias()` declarations in MODULE.bazel for all compat layer flags. This will work in Bazel 9, but is ignored in Bazel 8. This leads to a slight inconsistency. Consider the following set of flags set by a user: ``` --@protobuf//bazel/flags:protocopt=foo --protocopt=bar ``` In Bazel 9+, where the flag alias is respected, the final value of the flag will be `bar`. In Bazel 8, where we emulate `flag_alias()` by reconciling the two different values at analysis time, we always prefer the Starlark version (and cannot tell the relative order), so the final value of the flag will be `foo`. To avoid this, prefer setting the Starlark version of the flag whenever possible. PiperOrigin-RevId: 970834999 |
||
|---|---|---|
| .bazelci | ||
| .bcr | ||
| .github | ||
| bazel | ||
| benchmarks | ||
| build_defs | ||
| ci | ||
| cmake | ||
| compatibility | ||
| conformance | ||
| csharp | ||
| docs | ||
| editions | ||
| editors | ||
| examples | ||
| go | ||
| hpb | ||
| hpb_generator | ||
| java | ||
| lua | ||
| objectivec | ||
| patches/protobuf_v25 | ||
| php | ||
| pkg | ||
| python | ||
| ruby | ||
| rust | ||
| src | ||
| third_party | ||
| toolchain | ||
| upb | ||
| upb_generator | ||
| .bazelignore | ||
| .bazeliskrc | ||
| .bazelrc | ||
| .clang-format | ||
| .gitattributes | ||
| .gitignore | ||
| .gitmodules | ||
| .readthedocs.yml | ||
| appveyor.bat | ||
| appveyor.yml | ||
| BUILD.bazel | ||
| CMakeLists.txt | ||
| CODE_OF_CONDUCT.md | ||
| CONTRIBUTING.md | ||
| CONTRIBUTORS.txt | ||
| Disable_bundle_install.patch | ||
| fix_permissions.sh | ||
| generate_descriptor_proto.sh | ||
| global.json | ||
| google3_export_generated_files.sh | ||
| LICENSE | ||
| maven_dev_install.json | ||
| maven_install.json | ||
| MODULE.bazel | ||
| PrivacyInfo.xcprivacy | ||
| protobuf.bzl | ||
| Protobuf.podspec | ||
| protobuf_deps.bzl | ||
| protobuf_release.bzl | ||
| protobuf_version.bzl | ||
| README.md | ||
| regenerate_stale_files.sh | ||
| SECURITY.md | ||
| version.json | ||
| WORKSPACE | ||
| WORKSPACE.bzlmod | ||
Protocol Buffers - Google's data interchange format
Copyright 2008 Google LLC
Overview
Protocol Buffers (a.k.a., protobuf) are Google's language-neutral, platform-neutral, extensible mechanism for serializing structured data. You can learn more about it in protobuf's documentation.
This README file contains protobuf installation instructions. To install protobuf, you need to install the protocol compiler (used to compile .proto files) and the protobuf runtime for your chosen programming language.
Working With Protobuf Source Code
Most users will find working from supported releases to be the easiest path.
If you choose to work from the head revision of the main branch your build will occasionally be broken by source-incompatible changes and insufficiently-tested (and therefore broken) behavior.
If you are using C++ or otherwise need to build protobuf from source as a part of your project, you should pin to a release commit on a release branch.
This is because even release branches can experience some instability in between release commits.
Bazel with Bzlmod
Protobuf supports Bzlmod with Bazel 8 +. Users should specify a dependency on protobuf in their MODULE.bazel file as follows.
bazel_dep(name = "protobuf", version = <VERSION>)
Users can optionally override the repo name, such as for compatibility with WORKSPACE.
bazel_dep(name = "protobuf", version = <VERSION>, repo_name = "com_google_protobuf")
Bazel with WORKSPACE
Users can also add the following to their legacy WORKSPACE file.
Note that with the release of 30.x there are a few more load statements to properly set up rules_java and rules_python.
http_archive(
name = "com_google_protobuf",
strip_prefix = "protobuf-VERSION",
sha256 = ...,
url = ...,
)
load("@com_google_protobuf//:protobuf_deps.bzl", "protobuf_deps")
protobuf_deps()
load("@rules_java//java:rules_java_deps.bzl", "rules_java_dependencies")
rules_java_dependencies()
load("@rules_java//java:repositories.bzl", "rules_java_toolchains")
rules_java_toolchains()
load("@rules_python//python:repositories.bzl", "py_repositories")
py_repositories()
Protobuf Compiler Installation
The protobuf compiler is written in C++. If you are using C++, please follow the C++ Installation Instructions to install protoc along with the C++ runtime.
For non-C++ users, the simplest way to install the protocol compiler is to download a pre-built binary from our GitHub release page.
In the downloads section of each release, you can find pre-built binaries in
zip packages: protoc-$VERSION-$PLATFORM.zip. It contains the protoc binary
as well as a set of standard .proto files distributed along with protobuf.
If you are looking for an old version that is not available in the release page, check out the Maven repository.
These pre-built binaries are only provided for released versions. If you want to use the github main version at HEAD, or you need to modify protobuf code, or you are using C++, it's recommended to build your own protoc binary from source.
If you would like to build protoc binary from source, see the C++ Installation Instructions.
Protobuf Runtime Installation
Protobuf supports several different programming languages. For each programming language, you can find instructions in the corresponding source directory about how to install protobuf runtime for that specific language:
| Language | Source |
|---|---|
| C++ (include C++ runtime and protoc) | src |
| Java | java |
| Python | python |
| Objective-C | objectivec |
| C# | csharp |
| Ruby | ruby |
| Go | protocolbuffers/protobuf-go |
| PHP | php |
| Dart | dart-lang/protobuf |
| JavaScript | protocolbuffers/protobuf-javascript |
Quick Start
The best way to learn how to use protobuf is to follow the tutorials in our developer guide.
If you want to learn from code examples, take a look at the examples in the examples directory.
Documentation
The complete documentation is available at the Protocol Buffers doc site.
Support Policy
Read about our version support policy to stay current on support timeframes for the language libraries.
Developer Community
To be alerted to upcoming changes in Protocol Buffers and connect with protobuf developers and users, join the Google Group.