mozc/docs/build_mozc_in_docker.md

How to build Mozc in Docker

Summary

If you are not sure what the following commands do, please check the descriptions below and make sure the operations before running them.

curl -O https://raw.githubusercontent.com/google/mozc/master/docker/ubuntu24.04/Dockerfile
docker build --rm --tag mozc_ubuntu24.04 .
docker create --interactive --tty --name mozc_build mozc_ubuntu24.04

docker start mozc_build
docker exec mozc_build bazelisk build package --config oss_linux --config release_build
docker cp mozc_build:/home/mozc_builder/work/mozc/src/bazel-bin/unix/mozc.zip .

Introduction

Docker containers are available to build Mozc binaries for Linux desktop.

System Requirements

Currently, only Ubuntu 24.04 is tested to host the Docker container to build Mozc.

• Dockerfile for Ubuntu 24.04

Build in Docker

Set up Ubuntu 24.04 Docker container

curl -O https://raw.githubusercontent.com/google/mozc/master/docker/ubuntu24.04/Dockerfile
docker build --rm --tag mozc_ubuntu24.04 .
docker create --interactive --tty --name mozc_build mozc_ubuntu24.04

You may need to execute docker with sudo (e.g. sudo docker build ...).

Notes

• mozc_ubuntu24.04 is a Docker image name (customizable).
• mozc_build is a Docker container name (customizable).
• Don't forget to rebuild Docker container when Dockerfile is updated.

Build Mozc in Docker container

docker start mozc_build
docker exec mozc_build bazelisk build package --config oss_linux --config release_build
docker cp mozc_build:/home/mozc_builder/work/mozc/src/bazel-bin/unix/mozc.zip .

mozc.zip contains built files.

Notes

• You might want to execute docker stop after build.
• mozc_build is the Docker container name created in the above section.

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Build Mozc for Linux Desktop

bazelisk build package --config oss_linux --config release_build

Note: You might want to execute docker start --interactive mozc_build to enter the docker container before the above command.

package builds Mozc binaries and locates them into mozc.zip as follows.

build rule	install path
//server:mozc_server	/usr/lib/mozc/mozc_server
//gui/tool:mozc_tool	/usr/lib/mozc/mozc_tool
//renderer:mozc_renderer	/usr/lib/mozc/mozc_renderer
//unix/ibus/ibus_mozc	/usr/lib/ibus-mozc/ibus-engine-mozc
//unix/ibus:gen_mozc_xml	/usr/share/ibus/component/mozc.xml
//unix:icons	/usr/share/ibus-mozc/...
//unix:icons	/usr/share/icons/mozc/...
//unix/emacs:mozc.el	/usr/share/emacs/site-lisp/emacs-mozc/mozc.el
//unix/emacs:mozc_emacs_helper	/usr/bin/mozc_emacs_helper

Install paths are configurable by modifying src/config.bzl.

Unit tests

Run all tests

bazelisk test ... --config oss_linux --build_tests_only -c dbg

• ... means all targets under the current and subdirectories.

Run tests under the specific directories

bazelisk test base/... composer/... --config oss_linux --build_tests_only -c dbg

• <dir>/... means all targets under the <dir>/ directory.

Run tests without the specific directories

bazelisk test ... --config oss_linux --build_tests_only -c dbg -- -base/...

• -- means the end of the flags which start from -.
• -<dir>/... means exclusion of all targets under the dir.

Run the specific test

bazelisk test base:util_test --config oss_linux -c dbg

• util_test is defined in base/BUILD.bazel.

Output logs to stderr

bazelisk test base:util_test --config oss_linux --test_arg=--stderrthreshold=0 --test_output=all

• The --test_arg=--stderrthreshold=0 --test_output=all flags shows the output of unitests to stderr.

Build Mozc on other Linux environment

Note: This section is not about our officially supported build process.

Software requirements

• Python: 3.7 or later
• Ibus: 1.5.4 or later
  • libglib
• Qt6: 6.2.5 or later, or Qt 6.2.x with working around QTBUG-86080 by yourself
  • libgl

You may also need other libraries. See the configurations of Dockerfile and GitHub Actions.

Build configurations

To build Mozc on other Linux environment rather than the supported Docker environment, you might need to modify the following files.

• src/config.bzl - configuration of install paths, etc.
• src/.bazelrc - compiler flags, etc.
• src/MODULE.bazel - build dependencies.

Tips: the following command makes the specified file untracked by Git.

git update-index --assume-unchanged src/config.bzl

This command reverts the above change.

git update-index --no-assume-unchanged src/config.bzl

Forcing reconfigure external dependencies

You may have some build errors when you update build environment or configurations. In that case, try the following command to refetch external repositories.

bazelisk sync --configure

If the issue persists, also try the following command to clean Bazel's build cache

bazelisk clean --expunge

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Build Mozc for Linux Desktop with GYP (deprecated):

⚠️ The GYP build is deprecated and no longer supported.

Please check the previous version for more information. https://github.com/google/mozc/blob/2.29.5374.102/docs/build_mozc_in_docker.md#build-mozc-for-linux-desktop-with-gyp-maintenance-mode