How to Create a Release of GRPC Java (for Maintainers Only)

Build Environments

We deploy GRPC to Maven Central under the following systems:

  • Ubuntu 14.04 with Docker 13.03.0 that runs CentOS 6.9
  • Windows 7 64-bit with Visual Studio
  • Mac OS X 10.12.6

Other systems may also work, but we haven't verified them.

Prerequisites

Set Up OSSRH Account

If you haven't deployed artifacts to Maven Central before, you need to setup your OSSRH (OSS Repository Hosting) account.

  • Follow the instructions on this page to set up an account with OSSRH.
    • You only need to create the account, not set up a new project
    • Contact a gRPC maintainer to add your account after you have created it.

Common Variables

Many of the following commands expect release-specific variables to be set. Set them before continuing, and set them again when resuming.

$ MAJOR=1 MINOR=7 PATCH=0 # Set appropriately for new release
$ VERSION_FILES=(
  build.gradle
  android/build.gradle
  android-interop-testing/app/build.gradle
  core/src/main/java/io/grpc/internal/GrpcUtil.java
  cronet/build.gradle
  documentation/android-channel-builder.md
  examples/build.gradle
  examples/pom.xml
  examples/android/clientcache/app/build.gradle
  examples/android/helloworld/app/build.gradle
  examples/android/routeguide/app/build.gradle
  examples/example-kotlin/build.gradle
  examples/example-kotlin/android/helloworld/app/build.gradle
  )

Branching the Release

The first step in the release process is to create a release branch and bump the SNAPSHOT version. Our release branches follow the naming convention of v<major>.<minor>.x, while the tags include the patch version v<major>.<minor>.<patch>. For example, the same branch v1.7.x would be used to create all v1.7 tags (e.g. v1.7.0, v1.7.1).

  1. For master, change root build files to the next minor snapshot (e.g. 1.8.0-SNAPSHOT).

    $ git checkout -b bump-version master
    # Change version to next minor (and keep -SNAPSHOT)
    $ sed -i 's/[0-9]\+\.[0-9]\+\.[0-9]\+\(.*CURRENT_GRPC_VERSION\)/'$MAJOR.$((MINOR+1)).0'\1/' \
      "${VERSION_FILES[@]}"
    $ sed -i s/$MAJOR.$MINOR.$PATCH/$MAJOR.$((MINOR+1)).0/ \
      compiler/src/test{,Lite,Nano}/golden/Test{,Deprecated}Service.java.txt
    $ ./gradlew build
    $ git commit -a -m "Start $MAJOR.$((MINOR+1)).0 development cycle"
    
  2. Go through PR review and submit.

  3. Create the release branch starting just before your commit and push it to GitHub:

    $ git fetch upstream
    $ git checkout -b v$MAJOR.$MINOR.x \
      $(git log --pretty=format:%H --grep "^Start $MAJOR.$((MINOR+1)).0 development cycle$" upstream/master)^
    $ git push upstream v$MAJOR.$MINOR.x
    
  4. Go to Travis CI settings and add a Cron Job:

    • Branch: v$MAJOR.$MINOR.x
    • Interval: weekly
    • Options: Do not run if there has been a build in the last 24h
    • Click Add button
  5. Continue with Google-internal steps at go/grpc/java/releasing.

  6. Create a milestone for the next release.

  7. Move items out of the release milestone that didn't make the cut. Issues that may be backported should stay in the release milestone. Treat issues with the ‘release blocker’ label with special care.

Tagging the Release

  1. Verify there are no open issues in the release milestone. Open issues should either be deferred or resolved and the fix backported.

  2. For vMajor.Minor.x branch, change README.md to refer to the next release version. Also update the version numbers for protoc if the protobuf library version was updated since the last release.

    $ git checkout v$MAJOR.$MINOR.x
    $ git pull upstream v$MAJOR.$MINOR.x
    $ git checkout -b release
    # Bump documented versions. Don't forget protobuf version
    $ ${EDITOR:-nano -w} README.md
    $ git commit -a -m "Update README to reference $MAJOR.$MINOR.$PATCH"
    
  3. Change root build files to remove “-SNAPSHOT” for the next release version (e.g. 0.7.0). Commit the result and make a tag:

    # Change version to remove -SNAPSHOT
    $ sed -i 's/-SNAPSHOT\(.*CURRENT_GRPC_VERSION\)/\1/' "${VERSION_FILES[@]}"
    $ sed -i s/-SNAPSHOT// compiler/src/test{,Lite,Nano}/golden/TestService.java.txt
    $ ./gradlew build
    $ git commit -a -m "Bump version to $MAJOR.$MINOR.$PATCH"
    $ git tag -a v$MAJOR.$MINOR.$PATCH -m "Version $MAJOR.$MINOR.$PATCH"
    
  4. Change root build files to the next snapshot version (e.g. 0.7.1-SNAPSHOT). Commit the result:

    # Change version to next patch and add -SNAPSHOT
    $ sed -i 's/[0-9]\+\.[0-9]\+\.[0-9]\+\(.*CURRENT_GRPC_VERSION\)/'$MAJOR.$MINOR.$((PATCH+1))-SNAPSHOT'\1/' \
      "${VERSION_FILES[@]}"
    $ sed -i s/$MAJOR.$MINOR.$PATCH/$MAJOR.$MINOR.$((PATCH+1))-SNAPSHOT/ compiler/src/test{,Lite,Nano}/golden/TestService.java.txt
    $ ./gradlew build
    $ git commit -a -m "Bump version to $MAJOR.$MINOR.$((PATCH+1))-SNAPSHOT"
    
  5. Go through PR review and push the release tag and updated release branch to GitHub:

    $ git checkout v$MAJOR.$MINOR.x
    $ git merge --ff-only release
    $ git push upstream v$MAJOR.$MINOR.x
    $ git push upstream v$MAJOR.$MINOR.$PATCH
    
  6. Close the release milestone.

Build Artifacts

Trigger build as described in “Auto releasing using kokoro” at go/grpc/java/releasing.

It runs three jobs on Kokoro, one on each platform. See their scripts: linux_artifacts.sh, windows.bat, and unix.sh (called directly for OS X; called within the Docker environment on Linux). The mvn-artifacts/ outputs of each script is combined into a single folder and then processed by upload_artifacts.sh, which signs the files and uploads to Sonatype.

Releasing on Maven Central

Once all of the artifacts have been pushed to the staging repository, the repository should have been closed by upload_artifacts.sh. Closing triggers several sanity checks on the repository. If this completes successfully, the repository can then be released, which will begin the process of pushing the new artifacts to Maven Central (the staging repository will be destroyed in the process). You can see the complete process for releasing to Maven Central on the OSSRH site.

Build interop container image

We have containers for each release to detect compatibility regressions with old releases. Generate one for the new release by following the GCR image generation instructions.

Update README.md

After waiting ~1 day and verifying that the release appears on Maven Central, cherry-pick the commit that updated the README into the master branch and go through review process.

$ git checkout -b bump-readme master
$ git cherry-pick v$MAJOR.$MINOR.$PATCH^

Update version referenced by tutorials

Update the grpc_java_release_tag in _data/config.yml of the grpc.github.io repository.

Notify the Community

Finally, document and publicize the release.

  1. Add Release Notes for the new tag. The description should include any major fixes or features since the last release. You may choose to add links to bugs, PRs, or commits if appropriate.
  2. Post a release announcement to grpc-io (grpc-io@googlegroups.com). The title should be something that clearly identifies the release (e.g.GRPC-Java <tag> Released).
    1. Check if JCenter has picked up the new release (https://jcenter.bintray.com/io/grpc/) and include its availability in the release announcement email. JCenter should mirror everything on Maven Central, but users have reported delays.

Update Hosted Javadoc

Now we need to update gh-pages with the new Javadoc:

git checkout gh-pages
rm -r javadoc/
wget -O grpc-all-javadoc.jar "http://search.maven.org/remotecontent?filepath=io/grpc/grpc-all/$MAJOR.$MINOR.$PATCH/grpc-all-$MAJOR.$MINOR.$PATCH-javadoc.jar"
unzip -d javadoc grpc-all-javadoc.jar
patch -p1 < ga.patch
rm grpc-all-javadoc.jar
rm -r javadoc/META-INF/
git add -A javadoc
git commit -m "Javadoc for $MAJOR.$MINOR.$PATCH"

Push gh-pages to the main repository and verify the current version is live on grpc.io.