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/ubuntu22.04/Dockerfile
docker build --rm --tag mozc_ubuntu22.04 .
docker create --interactive --tty --name mozc_build mozc_ubuntu22.04

docker start mozc_build
docker exec mozc_build bazel build package --config oss_linux -c opt
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 Android JNI library and Linux desktop.

System Requirements

Currently, only Ubuntu 22.04 is tested to host the Docker container to build Mozc.

• Dockerfile for Ubuntu 22.04

Build in Docker

Set up Ubuntu 22.04 Docker container

curl -O https://raw.githubusercontent.com/google/mozc/master/docker/ubuntu22.04/Dockerfile
docker build --rm --tag mozc_ubuntu22.04 .
docker create --interactive --tty --name mozc_build mozc_ubuntu22.04

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

Notes

• mozc_ubuntu22.04 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 bazel build package --config oss_linux -c opt
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

bazel build package --config oss_linux -c opt

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

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

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

Run tests under the specific directories

bazel 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

bazel 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

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

• util_test is defined in base/BUILD.bazel.

Output logs to stderr

bazel test base:util_test --config oss_linux --test_arg=--logtostderr --test_output=all

• The --test_arg=--logtostderr --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/WORKSPACE.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

Clean build cache

You may have some build errors when you update build environment or configurations. In that case, cleaing the build cache possibly addresses the problem.

bazel clean

To clean the cache deeply, add the --expunge option.

bazel clean --expunge

Build Mozc library for Android:

Client code for Android apk is deprecated. (the last revision with Android client code is afb03dd).

The conversion engine for Android is built with Bazel.

bazel build package --config oss_android

package is an alias to build android/jni:mozc_lib.

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Build Mozc for Linux Desktop with GYP (maintenance mode):

⚠️ The GYP build no longer support the Ibus client and the GTK candidate window.

• https://github.com/google/mozc/issues/567

To keep using the GYP build without the Ibus client and the GTK candidate window at this moment, please add the --no_ibus_build and --no_gtk_build flags to build_mozc.py.

python3 build_mozc.py gyp
python3 build_mozc.py build -c Release package --no_ibus_build --no_gtk_build

package is an alias to build:

• //server:mozc_server
• //gui/tool:mozc_tool

You can also run unittests as follows.

python3 build_mozc.py runtests -c Debug

Differences between Bazel build and GYP build

GYP build is under maintenance mode. New features might be supported by Bazel only, and some features might be dropped as a trade-off to accept PRs.

Targets only for Bazel:

• Ibus client (//unix/ibus)
• AUX dictionary (//data/dictionary_oss:aux_dictionary)
• Filtered dictionary (//data/dictionary_oss:filtered_dictionary)
• SVS character input instead of CJK compatibility ideographs (//rewriter:single_kanji_rewriter)
• Zip code conversion (//server:mozc_server)
• Qt-based candidate window (//renderer:mozc_renderer)
• Build rules for icons (//unix/icons)

GYP Build configurations

For the build configurations, please check the previous version. https://github.com/google/mozc/blob/2.28.4880.102/docs/build_mozc_in_docker.md#gyp-build-configurations