This page documents the procedure to make an Apache BookKeeper release.

Introduction

The Apache BookKeeper project periodically declares and publishes releases. A release is one or more packages of the project artifact(s) that are approved for general public distribution and use. They may come with various degrees of caveat regarding their perceived quality and potential for change, such as “alpha”, “beta”, “incubating”, “stable”, etc.

The BookKeeper community treats releases with great importance. They are a public face of the project and most users interact with the project only through the releases. Releases are signed off by the entire BookKeeper community in a public vote.

Each release is executed by a Release Manager, who is selected among the BookKeeper committers. This document describes the process that the Release Manager follows to perform a release. Any changes to this process should be discussed and adopted on the dev@ mailing list.

Please remember that publishing software has legal consequences. This guide complements the foundation-wide Product Release Policy and Release Distribution Policy.

Overview

The release process consists of several steps:

  1. Decide to release
  2. Prepare for the release
  3. Build a release candidate
  4. Vote on the release candidate
  5. If necessary, fix any issues and go back to step 3.
  6. Finalize the release
  7. Promote the release

Decide to release

Deciding to release and selecting a Release Manager is the first step of the release process. This is a consensus-based decision of the entire community.

Anybody can propose a release on the dev@ mailing list, giving a solid argument and nominating a committer as the Release Manager (including themselves). There’s no formal process, no vote requirements, and no timing requirements. Any objections should be resolved by consensus before starting the release.

In general, the community prefers to have a rotating set of 3-5 Release Managers. Keeping a small core set of managers allows enough people to build expertise in this area and improve processes over time, without Release Managers needing to re-learn the processes for each release. That said, if you are a committer interested in serving the community in this way, please reach out to the community on the dev@ mailing list.

Checklist to proceed to the next step

  1. Community agrees to release
  2. Community selects a Release Manager

Prepare for the release

Before your first release, you should perform one-time configuration steps. This will set up your security keys for signing the release and access to various release repositories.

To prepare for each release, you should audit the project status both in the JIRA issue tracker and the Github issue tracker, and do necessary bookkeeping. Finally, you should create a release branch from which individual release candidates will be built.

One-time setup instructions

GPG Key

You need to have a GPG key to sign the release artifacts. Please be aware of the ASF-wide release signing guidelines. If you don’t have a GPG key associated with your Apache account, please create one according to the guidelines and upload your key to a public key server.

It is important to link your GPG key into the Apache web of trust. You can reach out other committers in Apache BookKeeper community for signing your key.

Once you have a GPG key associated with your Apache count, then:

First, Determine your Apache GPG Key and Key ID, as follows:

gpg --list-keys

This will list your GPG keys. One of these should reflect your Apache account, for example:

--------------------------------------------------
pub   2048R/845E6689 2016-02-23
uid                  Nomen Nescio <anonymous@apache.org>
sub   2048R/BA4D50BE 2016-02-23

Here, the key ID is the 8-digit hex string in the pub line: 845E6689.

Second, add your Apache GPG key to the BookKeeper’s KEYS file in dist.


# checkout the svn folder that contains the KEYS file
svn co https://dist.apache.org/repos/dist/release/bookkeeper bookkeeper_dist
cd bookkeeper_dist

# Export the key in ascii format and append it to the file
( gpg --list-sigs $USER@apache.org
  gpg --export --armor $USER@apache.org ) >> KEYS

# Commit to svn
svn ci -m "Added gpg key for $USER"

Once you committed, please verify if your GPG key shows up in the BookkKeeper’s KEYS file in dist.

Third, configure git to use this key when signing code by giving it your key ID, as follows:

git config --global user.signingkey 845E6689

You may drop the --global option if you’d prefer to use this key for the current repository only.

You may wish to start gpg-agent to unlock your GPG key only once using your passphrase. Otherwise, you may need to enter this passphrase hundreds of times. The setup for gpg-agent varies based on operating system, but may be something like this:

eval $(gpg-agent --daemon --no-grab --write-env-file $HOME/.gpg-agent-info)
export GPG_TTY=$(tty)
export GPG_AGENT_INFO

Access to Apache Nexus repository

Configure access to the Apache Nexus repository, which enables final deployment of releases to the Maven Central Repository.

  1. You log in with your Apache account.
  2. Confirm you have appropriate access by finding org.apache.bookkeeper under Staging Profiles.
  3. Navigate to your Profile (top right dropdown menu of the page).
  4. Choose User Token from the dropdown, then click Access User Token. Copy a snippet of the Maven XML configuration block.
  5. Insert this snippet twice into your global Maven settings.xml file, typically ${HOME}/.m2/settings.xml. The end result should look like this, where TOKEN_NAME and TOKEN_PASSWORD are your secret tokens:

     <settings>
       <servers>
         <server>
           <id>apache.releases.https</id>
           <username>TOKEN_NAME</username>
           <password>TOKEN_PASSWORD</password>
         </server>
         <server>
           <id>apache.snapshots.https</id>
           <username>TOKEN_NAME</username>
           <password>TOKEN_PASSWORD</password>
         </server>
       </servers>
     </settings>
    

Create a new version in JIRA and Github

When contributors resolve an issue in JIRA, they are tagging it with a release that will contain their changes. With the release currently underway, new issues should be resolved against a subsequent future release. Therefore, you should create a release item for this subsequent release, as follows:

  1. In JIRA, navigate to the BookKeeper > Administration > Versions.
  2. Add a new release: choose the next minor version number compared to the one currently underway, select today’s date as the Start Date, and choose Add.
  3. In Github, navigate to the Issues > Milestones.
  4. Add a new milestone: choose the next minor version number compared to the one currently underway, select a day that is 3-months from now as the Due Date, write a description Release x.y.z and choose Create milestone.

Triage release-blocking issues in JIRA and Github

JIRA

There could be outstanding release-blocking issues, which should be triaged before proceeding to build a release candidate. We track them by assigning a specific Fix version field even before the issue resolved.

The list of release-blocking issues is available at the version status page. Triage each unresolved issue with one of the following resolutions:

  • If the issue has been resolved and JIRA was not updated, resolve it accordingly.
  • If the issue has not been resolved and it is acceptable to defer this until the next release, update the Fix Version field to the new version you just created. Please consider discussing this with stakeholders and the dev@ mailing list, as appropriate.
  • If the issue has not been resolved and it is not acceptable to release until it is fixed, the release cannot proceed. Instead, work with the BookKeeper community to resolve the issue.

Github

There could be outstanding release-blocking issues, which should be triaged before proceeding to build a release candidate. We track them by assigning a specific Milestone field even before the issue resolved.

The list of release-blocking issues is available at the milestones page. Triage each unresolved issue with one of the following resolutions:

  • If the issue has been resolved and was not updated, close it accordingly.
  • If the issue has not been resolved and it is acceptable to defer this until the next release, update the Milestone field to the new milestone you just created. Please consider discussing this with stakeholders and the dev@ mailing list, as appropriate.
  • If the issue has not been resolved and it is not acceptable to release until it is fixed, the release cannot proceed. Instead, work with the BookKeeper community to resolve the issue.

Review Release Notes in JIRA and Github

JIRA

JIRA automatically generates Release Notes based on the Fix Version field applied to issues. Release Notes are intended for BookKeeper users (not BookKeeper committers/contributors). You should ensure that Release Notes are informative and useful.

Open the release notes from the version status page by choosing the release underway and clicking Release Notes.

You should verify that the issues listed automatically by JIRA are appropriate to appear in the Release Notes. Specifically, issues should:

  • Be appropriately classified as Bug, New Feature, Improvement, etc.
  • Represent noteworthy user-facing changes, such as new functionality, backward-incompatible API changes, or performance improvements.
  • Have occurred since the previous release; an issue that was introduced and fixed between releases should not appear in the Release Notes.
  • Have an issue title that makes sense when read on its own.

Adjust any of the above properties to the improve clarity and presentation of the Release Notes.

Github

Unlike JIRA, Github does not automatically generates Release Notes based on the Milestone field applied to issues. We can use github-changelog-generator to generate a ChangeLog for a milestone in future.

For Github, we can use the milestone link in the Release Notes. E.g. Release 4.5.0 milestone.

Prepare Release Notes

After review the release notes on both JIRA and Github, you should write a releaseNotes under site/docs/${release_version}/overview/releaseNotes.md and then send out a pull request for review.

4.5.0 Release Notes is a good example to follow.

Create a release branch

Release candidates are built from a release branch. As a final step in preparation for the release, you should create the release branch, push it to the code repository, and update version information on the original branch.

Check out the version of the codebase from which you start the release. For a new minor or major release, this may be HEAD of the master branch. To build a hotfix/incremental release, instead of the master branch, use the release tag of the release being patched. (Please make sure your cloned repository is up-to-date before starting.)

git checkout <master branch OR release tag>

Set up a few environment variables to simplify Maven commands that follow. (We use bash Unix syntax in this guide.)

MAJOR_VERSION="4.5"
VERSION="4.5.0"
NEXT_VERSION="4.6.0"
BRANCH_NAME="branch-${MAJOR_VERSION}"
DEVELOPMENT_VERSION="${NEXT_VERSION}-SNAPSHOT"

Version represents the release currently underway, while next version specifies the anticipated next version to be released from that branch. Normally, 4.5.0 is followed by 4.6.0, while 4.5.0 is followed by 4.5.1.

Use Maven release plugin to create the release branch and update the current branch to use the new development version. This command applies for the new major or minor version.

This command automatically check in and tag your code in the code repository configured in the SCM. It is recommended to do a “dry run” before executing the command. To “dry run”, you can provide “-DdryRun” at the end of this command. “dry run” will generate some temporary files in the project folder, you can remove them by running “mvn release:clean”.

mvn release:branch \
    -DbranchName=${BRANCH_NAME} \
    -DdevelopmentVersion=${DEVELOPMENT_VERSION} \
    [-DdryRun]

If you failed at the middle of running this command, please check if you have push permissions on github.com. You need use personal access token rather than your own password, if you enabled 2 factor authentication.

On failures, you need to reset on failures:

$ git reset –hard apache/ $ git branch -D ${BRANCH_NAME}

However, if you are doing an incremental/hotfix release, please run the following command after checking out the release tag of the release being patched.

mvn release:branch \
    -DbranchName=${BRANCH_NAME} \
    -DupdateWorkingCopyVersions=false \
    -DupdateBranchVersions=true \
    -DreleaseVersion="${VERSION}-SNAPSHOT" \
    [-DdryRun]

Check out the release branch.

git checkout ${BRANCH_NAME}

The rest of this guide assumes that commands are run in the root of a repository on ${BRANCH_NAME} with the above environment variables set.

Checklist to proceed to the next step

  1. Release Manager’s GPG key is published to dist.apache.org
  2. Release Manager’s GPG key is configured in git configuration
  3. Release Manager has org.apache.bookkeeper listed under Staging Profiles in Nexus
  4. Release Manager’s Nexus User Token is configured in settings.xml
  5. JIRA release item for the subsequent release has been created
  6. Github milestone item for the subsequet release has been created
  7. There are no release blocking JIRA issues
  8. There are no release blocking Github issues
  9. Release Notes in JIRA have been audited and adjusted
  10. Release Notes for Github Milestone is generated, audited and adjusted
  11. Release branch has been created
  12. Originating branch has the version information updated to the new version

Build a release candidate

The core of the release process is the build-vote-fix cycle. Each cycle produces one release candidate. The Release Manager repeats this cycle until the community approves one release candidate, which is then finalized.

Build and stage Java artifacts with Maven

TODO: Currently we have to build and stage maven artifacts manually, because it requires pushing the artifacts to apache staging. We should look for a solution to automate that.

Set up a few environment variables to simplify Maven commands that follow. This identifies the release candidate being built. Start with release candidate number equal to 0 and increment it for each candidate.

RC_NUM="0"
TAG="release-${VERSION}"
RC_DIR="bookkeeper-${VERSION}-rc${RC_NUM}"

Please make sure gpg command is in your $PATH. The maven release plugin use gpg to sign generated jars and packages.

Use Maven release plugin to build the release artifacts, as follows:

mvn release:prepare \
    -Dresume=false \
    -DreleaseVersion=${VERSION} \
    -Dtag=${TAG} \
    -DupdateWorkingCopyVersions=false \
    [-DdryRun] \
    [-Darguments="-Dmaven.javadoc.skip=true -DskipTests=true"] \ // to skip javadoc and tests
    [-Dresume=true] // resume prepare if it is interrupted in the middle

Use Maven release plugin to stage these artifacts on the Apache Nexus repository, as follows:

mvn release:perform [-DdryRun] [-Darguments="-Dmaven.javadoc.skip=true -DskipTests=true"] [-Dresume=true]

If release:perform failed, delete the release tag: git tag -d ${VERSION} && git push apache :refs/tags/${VERSION}

Also, you need to check the git commits on the github and if needed you may have to force push backed out local git branch to github again.

After reset, run release:prepare again.

Review all staged artifacts. They should contain all relevant parts for each module, including pom.xml, jar, test jar, source, test source, javadoc, etc. Artifact names should follow the existing format in which artifact name mirrors directory structure, e.g., bookkeeper-server. Carefully review any new artifacts.

Close the staging repository on Apache Nexus. When prompted for a description, enter “Apache BookKeeper, version X, release candidate Y”.

Stage source release on dist.apache.org

Copy the source release to the dev repository of dist.apache.org.

  1. If you have not already, check out the BookKeeper section of the dev repository on dist.apache.org via Subversion. In a fresh directory:

     svn co https://dist.apache.org/repos/dist/dev/bookkeeper
    
  2. Make a directory for the new release:

     mkdir bookkeeper/${RC_DIR}
    
  3. Copy the BookKeeper source and binary distribution, and their GPG signatures:

     cp target/bookkeeper-${VERSION}-src.tar.gz bookkeeper/${RC_DIR}/bookkeeper-${VERSION}-src.tar.gz
     cp target/bookkeeper-${VERSION}-src.tar.gz.asc bookkeeper/${RC_DIR}/bookkeeper-${VERSION}-src.tar.gz.asc
     cp bookkeeper-server/target/bookkeeper-server-${VERSION}-bin.tar.gz bookkeeper/${RC_DIR}/bookkeeper-server-${VERSION}-bin.tar.gz
     cp bookkeeper-server/target/bookkeeper-server-${VERSION}-bin.tar.gz.asc bookkeeper/${RC_DIR}/bookkeeper-server-${VERSION}-bin.tar.gz.asc
    
  4. Sign the BookKeeper source and binary distribution.

     cd bookkeeper/${RC_DIR}
     md5sum bookkeeper-${VERSION}-src.tar.gz > bookkeeper-${VERSION}-src.tar.gz.md5
     shasum bookkeeper-${VERSION}-src.tar.gz > bookkeeper-${VERSION}-src.tar.gz.sha1
     md5sum bookkeeper-server-${VERSION}-bin.tar.gz > bookkeeper-server-${VERSION}-bin.tar.gz.md5
     shasum bookkeeper-server-${VERSION}-bin.tar.gz > bookkeeper-server-${VERSION}-bin.tar.gz.sha1
    
  5. Go back to BookKeeper directory, add and commit all the files.

     cd ..
     svn add ${RC_DIR}
     svn commit
    
  6. Verify that files are present.

Checklist to proceed to the next step

  1. Maven artifacts deployed to the staging repository of repository.apache.org
  2. Source and Binary distribution deployed to the dev repository of dist.apache.org

Vote on the release candidate

Once you have built and individually reviewed the release candidate, please share it for the community-wide review. Please review foundation-wide voting guidelines for more information.

Start the review-and-vote thread on the dev@ mailing list. Here’s an email template; please adjust as you see fit.

From: Release Manager
To: dev@bookkeeper.apache.org
Subject: [VOTE] Release 4.5.0, release candidate #0

Hi everyone,
Please review and vote on the release candidate #0 for the version 0.4.0, as follows:
[ ] +1, Approve the release
[ ] -1, Do not approve the release (please provide specific comments)

The complete staging area is available for your review, which includes:
* Release notes [1]
* The official Apache source and binary distributions to be deployed to dist.apache.org [2]
* All artifacts to be deployed to the Maven Central Repository [3]
* Source code tag "release-4.5.0" [4]

BookKeeper's KEY file contains PGP keys we use to sign this release:
https://dist.apache.org/repos/dist/release/bookkeeper/KEYS

Please down this packages and review this release candidate:

- Review release notes
- Download the source package (verify md5, shasum, and asc) and follow the
instructions to build and run the bookkeeper service.
- Download the binary package (verify md5, shasum, and asc) and follow the
instructions to run the bookkeeper service.
- Review maven repo, release tag, licenses, and any other things you think
it is important to a release.

The vote will be open for at least 72 hours. It is adopted by majority approval, with at least 3 PMC affirmative votes.

Thanks,
Release Manager

[1] link
[2] link
[3] link
[4] link
[5] link

If there are any issues found in the release candidate, reply on the vote thread to cancel the vote. There’s no need to wait 72 hours. Proceed to the Fix Issues step below and address the problem. However, some issues don’t require cancellation. For example, if an issue is found in the website pull request, just correct it on the spot and the vote can continue as-is.

If there are no issues, reply on the vote thread to close the voting. Then, tally the votes in a separate email. Here’s an email template; please adjust as you see fit. (NOTE: the approver list are binding approvers.)

From: Release Manager
To: dev@bookkeeper.incubator.apache.org
Subject: [RESULT] [VOTE] Release 0.4.0, release candidate #0

I'm happy to announce that we have unanimously approved this release.

There are XXX approving votes, XXX of which are binding:
* approver 1
* approver 2
* approver 3
* approver 4

There are no disapproving votes.

Thanks everyone!

Checklist to proceed to the finalization step

  1. Community votes to release the proposed candidate

Fix any issues

Any issues identified during the community review and vote should be fixed in this step.

Code changes should be proposed as standard pull requests to the master branch and reviewed using the normal contributing process. Then, relevant changes should be cherry-picked into the release branch. The cherry-pick commits should then be proposed as the pull requests against the release branch, again reviewed and merged using the normal contributing process.

Once all issues have been resolved, you should go back and build a new release candidate with these changes.

Checklist to proceed to the next step

  1. Issues identified during vote have been resolved, with fixes committed to the release branch.

Finalize the release

Once the release candidate has been reviewed and approved by the community, the release should be finalized. This involves the final deployment of the release candidate to the release repositories, merging of the website changes, etc.

Deploy artifacts to Maven Central Repository

Use the Apache Nexus repository to release the staged binary artifacts to the Maven Central repository. In the Staging Repositories section, find the relevant release candidate orgapachebookkeeper-XXX entry and click Release. Drop all other release candidates that are not being released.

Deploy source release to dist.apache.org

Copy the source release from the dev repository to the release repository at dist.apache.org using Subversion.

svn move https://dist.apache.org/repos/dist/dev/bookkeeper/bookkeeper-${VERSION}-rc${RC_NUM} https://dist.apache.org/repos/dist/release/bookkeeper/bookkeeper-${VERSION}

Update Website

  1. Create the documentation for ${VERSION}. Run the release.sh to generate the branch for ${VERSION} and bump the versions for website documentation.

     $ cd site
     $ ./site/release.sh
    

    Once run the release.sh, please send a pull request for it and get approval from any committers, then merge it. The CI job will automatically update the website in a few minutes. Please review the website to make sure the documentation for ${VERSION} is live.

  2. Merge the Release Notes pull request and make sure the Release Notes is updated.

Update Dockerfile

  1. Update the BK_VERSION and GPG_KEY in docker/Dockerfile (e.g. Pull Request 436 ), send a pull request for review and get an approval from the community.

  2. Once the pull request is approved, merge this pull request into master and make sure it is cherry-picked into corresponding branch.

  3. After this pull request is merged, you need to cherry-pick the change to the release tag.

     // create a cherry-pick branch
     $ git checkout ${TAG}
     $ git checkout -b ${TAG}_cherrypick
     $ git cherry-pick <GIT SHA>
     // remove the release tag locally and remotely
     $ git tag -d ${TAG}
     $ git push apache :${TAG}
     // re-tag based on the cherry-pick branch
     $ git tag ${TAG}
     $ git push apache ${TAG}
    
  4. Verify the docker hub to see if a new build for the given tag is build.

Mark the version as released in JIRA and Github

In JIRA, inside version management, hover over the current release and a settings menu will appear. Click Release, and select today’s date.

In Github, inside milestones, hover over the current milestone and click close button to close a milestone and set today’s date as due-date.

Checklist to proceed to the next step

  • Maven artifacts released and indexed in the Maven Central Repository
  • Source and Binary distribution available in the release repository of dist.apache.org
  • Website is updated with new release
  • Docker image is built with new release
  • Release tagged in the source code repository
  • Release version finalized in JIRA and Github

Promote the release

Once the release has been finalized, the last step of the process is to promote the release within the project and beyond.

Apache mailing lists

  • Announce on the dev@ mailing list that the release has been finished.
  • Announce on the release on the user@ mailing list, listing major improvements and contributions.
  • Announce the release on the announce@apache.org mailing list.

NOTE: Make sure sending the announce email using apache email, otherwise announce@apache.org will reject your email.

From: xxx@apache.org
To: dev@bookkeeper.apache.org, dev@bookkeeper.apache.org, announce@apache.org
Subject: [ANNOUNCE] Apache BookKeeper x.y.z released
 
The Apache BookKeeper team is proud to announce Apache BookKeeper version
x.y.z.

Apache BookKeeper is a scalable, fault-tolerant, and low-latency storage service optimized for
real-time workloads. It has been used for a fundamental service to build reliable services.
It is also the log segment store for Apache DistributedLog and the message store for Apache Pulsar.

This is the N release of the Apache BookKeeper.

[highlights the release and why users need to try the release]
 
For BookKeeper release details and downloads, visit:
 
[download link]
 
BookKeeper x.y.z Release Notes are at:

[release notes link]
 
We would like to thank the contributors that made the release possible.
 
Regards,
 
The BookKeeper Team

Recordkeeping

Use reporter.apache.org to seed the information about the release into future project reports.

Social media

Tweet, post on Facebook, LinkedIn, and other platforms. Ask other contributors to do the same.

Checklist to declare the process completed

  1. Release announced on the user@ mailing list.
  2. Blog post published, if applicable.
  3. Apache Software Foundation press release published.
  4. Release announced on social media.
  5. Completion declared on the dev@ mailing list.

Improve the process

It is important that we improve the release processes over time. Once you’ve finished the release, please take a step back and look what areas of this process and be improved. Perhaps some part of the process can be simplified. Perhaps parts of this guide can be clarified.

If we have specific ideas, please start a discussion on the dev@ mailing list and/or propose a pull request to update this guide. Thanks!