grpcio-tools 1.31.0rc2

Protobuf code generator for gRPC

Package for gRPC Python tools.

Supported Python Versions

Python >= 3.5

Deprecated Python Versions

Python == 2.7. Python 2.7 support will be removed on January 1, 2020.

Installation

The gRPC Python tools package is available for Linux, Mac OS X, and Windows running Python 2.7.

Installing From PyPI

If you are installing locally…

$ pip install grpcio-tools

Else system wide (on Ubuntu)…

$ sudo pip install grpcio-tools

If you’re on Windows make sure that you installed the pip.exe component when you installed Python (if not go back and install it!) then invoke:

$ pip.exe install grpcio-tools

Windows users may need to invoke pip.exe from a command line ran as administrator.

n.b. On Windows and on Mac OS X one must have a recent release of pip to retrieve the proper wheel from PyPI. Be sure to upgrade to the latest version!

You might also need to install Cython to handle installation via the source distribution if gRPC Python’s system coverage with wheels does not happen to include your system.

Installing From Source

Building from source requires that you have the Python headers (usually a package named python-dev) and Cython installed. It further requires a GCC-like compiler to go smoothly; you can probably get it to work without GCC-like stuff, but you may end up having a bad time.

$ export REPO_ROOT=grpc  # REPO_ROOT can be any directory of your choice
$ git clone -b RELEASE_TAG_HERE https://github.com/grpc/grpc $REPO_ROOT
$ cd $REPO_ROOT
$ git submodule update --init

$ cd tools/distrib/python/grpcio_tools
$ python ../make_grpcio_tools.py

# For the next command do `sudo pip install` if you get permission-denied errors
$ GRPC_PYTHON_BUILD_WITH_CYTHON=1 pip install .

You cannot currently install Python from source on Windows. Things might work out for you in MSYS2 (follow the Linux instructions), but it isn’t officially supported at the moment.

Troubleshooting

Help, I …

• … see a pkg_resources.VersionConflict when I try to install grpc

  This is likely because pip doesn’t own the offending dependency, which in turn is likely because your operating system’s package manager owns it. You’ll need to force the installation of the dependency:

  pip install --ignore-installed $OFFENDING_DEPENDENCY

  For example, if you get an error like the following:

  Traceback (most recent call last):
  File "<string>", line 17, in <module>
   ...
  File "/usr/lib/python2.7/dist-packages/pkg_resources.py", line 509, in find
    raise VersionConflict(dist, req)
  pkg_resources.VersionConflict: (six 1.8.0 (/usr/lib/python2.7/dist-packages), Requirement.parse('six>=1.10'))

  You can fix it by doing:

  sudo pip install --ignore-installed six

• … see compiler errors on some platforms when either installing from source or from the source distribution

  If you see

  /tmp/pip-build-U8pSsr/cython/Cython/Plex/Scanners.c:4:20: fatal error: Python.h: No such file or directory
  #include "Python.h"
                  ^
  compilation terminated.

  You can fix it by installing python-dev package. i.e

  sudo apt-get install python-dev

  If you see something similar to:

  third_party/protobuf/src/google/protobuf/stubs/mathlimits.h:173:31: note: in expansion of macro 'SIGNED_INT_MAX'
  static const Type kPosMax = SIGNED_INT_MAX(Type); \\
                             ^

  And your toolchain is GCC (at the time of this writing, up through at least GCC 6.0), this is probably a bug where GCC chokes on constant expressions when the -fwrapv flag is specified. You should consider setting your environment with CFLAGS=-fno-wrapv or using clang (CC=clang).

Usage

Given protobuf include directories $INCLUDE, an output directory $OUTPUT, and proto files $PROTO_FILES, invoke as:

$ python -m grpc.tools.protoc -I$INCLUDE --python_out=$OUTPUT --grpc_python_out=$OUTPUT $PROTO_FILES

To use as a build step in distutils-based projects, you may use the provided command class in your setup.py:

setuptools.setup(
  # ...
  cmdclass={
    'build_proto_modules': grpc.tools.command.BuildPackageProtos,
  }
  # ...
)

Invocation of the command will walk the project tree and transpile every .proto file into a _pb2.py file in the same directory.

Note that this particular approach requires grpcio-tools to be installed on the machine before the setup script is invoked (i.e. no combination of setup_requires or install_requires will provide access to grpc.tools.command.BuildPackageProtos if it isn’t already installed). One way to work around this can be found in our grpcio-health-checking package:

class BuildPackageProtos(setuptools.Command):
  """Command to generate project *_pb2.py modules from proto files."""
  # ...
  def run(self):
    from grpc.tools import command
    command.build_package_protos(self.distribution.package_dir[''])

Now including grpcio-tools in setup_requires will provide the command on-setup as desired.

For more information on command classes, consult distutils and setuptools documentation.