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# Release Guide

## Introduction

The Apache Celeborn 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 Celeborn 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 Celeborn community in a
public vote.

Each release is executed by a Release Manager, who is selected among the Celeborn 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](mailto:dev@celeborn.apache.org).

Please remember that publishing software has legal consequences. This guide complements the foundation-wide
[Product Release Policy](https://www.apache.org/dev/release.html) and
[Release Distribution Policy](https://www.apache.org/dev/release-distribution).

### Overview

The release process consists of several steps:

1. Decide to release
2. Prepare for the release
3. Cut branch off for __feature__ release
4. Build a release candidate
5. Vote on the release candidate
6. If necessary, fix any issues and go back to step 3.
7. Finalize the release
8. Promote the release
9. Remove the dist repo directories for deprecated release candidates
10. Publish docker image

## 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](mailto:dev@celeborn.apache.org), 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 1-2 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](mailto:dev@celeborn.apache.org).

### 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.

### One-time setup instructions

#### ASF authentication

The environments `ASF_USERNAME` and `ASF_PASSWORD` have been used in several places and several times in the release
process, you can either one-time set up them in `~/.bashrc` or `~/.zshrc`, or export them in terminal every time.

```shell
export ASF_USERNAME=<your apache username>
export ASF_PASSWORD=<your apache password>
```

#### Java Home

An available environment variable `JAVA_HOME`, you can do `echo $JAVA_HOME` to check it.
Note that, the Java version should be 8.

#### Subversion

Besides on `git`, `svn` is also required for Apache release, please refer to
https://www.apache.org/dev/version-control.html#https-svn for details.

#### GPG Key

You need to have a GPG key to sign the release artifacts. Please be aware of the ASF-wide
[release signing guidelines](https://www.apache.org/dev/release-signing.html). If you don’t have a GPG key associated
with your Apache account, please create one according to the guidelines.

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

```shell
gpg --list-keys --keyid-format SHORT
```

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

```shell
pub   rsa4096 2021-08-30 [SC]
      8FC8075E1FDC303276C676EE8001952629BCC75D
uid           [ultimate] Cheng Pan <chengpan@apache.org>
sub   rsa4096 2021-08-30 [E]
```

> Note: To follow the [Apache's release specification](https://infra.apache.org/release-signing.html#note), all new RSA keys generated should be at least 4096 bits. Do not generate new DSA keys.

Here, the key ID is the 8-digit hex string in the pub line: `29BCC75D`.

To export the PGP public key, using:

```shell
gpg --armor --export 29BCC75D
```

If you have more than one gpg key, you can specify the default key as the following:

```
echo 'default-key <key-fpr>' > ~/.gnupg/gpg.conf
```

The last step is to update the KEYS file with your code signing key
https://www.apache.org/dev/openpgp.html#export-public-key

```shell
svn checkout --depth=files "https://dist.apache.org/repos/dist/release/celeborn" tmp/svn-celeborn

(gpg --list-sigs "${ASF_USERNAME}@apache.org" && gpg --export --armor "${ASF_USERNAME}@apache.org") >> tmp/svn-celeborn/KEYS

svn commit --username "${ASF_USERNAME}" --password "${ASF_PASSWORD}" --message "Update KEYS" tmp/svn-celeborn
```

In order to make yourself have the right permission to stage java artifacts in Apache Nexus staging repository, please submit your GPG public key to ubuntu server via

```shell
gpg --keyserver hkp://keyserver.ubuntu.com --send-keys ${PUBLIC_KEY} # send public key to ubuntu server
gpg --keyserver hkp://keyserver.ubuntu.com --recv-keys ${PUBLIC_KEY} # verify
```

## Cut branch if for feature release

Celeborn use version pattern `{MAJOR_VERSION}.{MINOR_VERSION}.{PATCH_VERSION}[-{OPTIONAL_SUFFIX}]`, e.g. `0.6.0`.
__Feature Release__ means `MAJOR_VERSION` or `MINOR_VERSION` changed, and __Patch Release__ means `PATCH_VERSION` changed.

The main step towards preparing a feature release is to create a release branch. This is done via standard Git branching
mechanism and should be announced to the community once the branch is created.

> Note: If you are releasing a patch version, you can ignore this step.

The release branch pattern is `branch-{MAJOR_VERSION}.{MINOR_VERSION}`, e.g. `branch-0.6`.

After cutting release branch, don't forget bump version in `master` branch.

## Build a release candidate

> Don't forget to switch to the release branch!

- Set environment variables.

```shell
export RELEASE_VERSION=<release version, e.g. 0.6.0>
export RELEASE_RC_NO=<RC number, e.g. 0>
export NEXT_VERSION=<e.g. 0.6.1>
```

- Bump version, and create a git tag for the release candidate.

Considering that other committers may merge PRs during your release period, you should accomplish the version change
first, and then come back to the release candidate tag to continue the rest release process.

The tag pattern is `v${RELEASE_VERSION}-rc${RELEASE_RC_NO}`, e.g. `v0.6.0-rc0`

> NOTE: After all the voting passed, be sure to create a final tag with the pattern: `v${RELEASE_VERSION}`

```shell
# Bump to the release version
# vim pom.xml <project.version>${RELEASE_VERSION}</project.version>
# vim version.sbt
# Regenerate the openapi-client code
build/sbt "clean;celeborn-openapi-client/generate"
git commit -am "[RELEASE] Bump ${RELEASE_VERSION}"

# Create tag
git tag v${RELEASE_VERSION}-rc${RELEASE_RC_NO}

# Prepare for the next development version
# vim pom.xml <project.version>${RELEASE_VERSION}</project.version>
# vim version.sbt
# Regenerate the openapi-client code
build/sbt "clean;celeborn-openapi-client/generate"
git commit -am "[RELEASE] Bump ${NEXT_VERSION}-SNAPSHOT"

# Push branch to apache remote repo
git push apache

# Push tag to apache remote repo
git push apache v${RELEASE_VERSION}-rc${RELEASE_RC_NO}

# Go back to release candidate tag 
git checkout v${RELEASE_VERSION}-rc${RELEASE_RC_NO}
```

- Package source and binary artifacts, and upload them to the Apache staging SVN repo. Publish jars to the Apache
  staging Maven repo.

```shell
# Checkout to the release tag
git checkout v${RELEASE_VERSION}-rc${RELEASE_RC_NO}

build/release/release.sh publish
```

To make your release available in the staging repository, you must close the staging repo in the [Apache Nexus](https://repository.apache.org/#stagingRepositories). Until you close, you can re-run deploying to staging multiple times. But once closed, it will create a new staging repo. So ensure you close this, so that the next RC (if need be) is on a new repo. Once everything is good, close the staging repository on Apache Nexus.

- Generate a pre-release note from GitHub for the subsequent voting.

Goto the [release page](https://github.com/apache/celeborn/releases) and click the "Draft a new release" button, then it would jump to a new page to prepare the release.

Filling in all the necessary information required by the form. And in the bottom of the form, choose the "This is a pre-release" checkbox. Finally, click the "Publish release" button to finish the step.

> Note: the pre-release note is used for voting purposes. It would be marked with a **Pre-release** tag. After all the voting works(dev and general) are finished, do not forget to inverse the "This is a pre-release" checkbox. The pre-release version comes from vx.y.z-rcN tags, and the final version should come from vx.y.z tags.

## Vote on the release candidate

The release voting takes place on the Apache Celeborn developers list.

- If possible, attach a draft of the release notes with the email.
- Recommend represent voting closing time in UTC format.
- Make sure the email is in text format and the links are correct.

Once the vote is done, you should also send out a summary email with the totals, with a subject that looks
something like __[VOTE][RESULT] Release Apache Celeborn ...__

## Finalize the Release

__Be Careful!__

__THIS STEP IS IRREVERSIBLE so make sure you selected the correct staging repository.__
__Once you move the artifacts into the release folder, they cannot be removed.__

After the vote passes, to upload the binaries to Apache mirrors, you move the binaries from dev directory (this should
be where they are voted) to release directory. This "moving" is the only way you can add stuff to the actual release
directory. (Note: only PMC members can move to release directory)

Move the subdirectory in "dev" to the corresponding directory in "release". If you've added your signing key to the
KEYS file, also update the release copy.

```shell
build/release/release.sh finalize
```

Verify that the resources are present in https://www.apache.org/dist/celeborn/. It may take a while for them to be visible.
This will be mirrored throughout the Apache network.

For Maven Central Repository, you can Release from the [Apache Nexus Repository Manager](https://repository.apache.org/).
Log in, open "Staging Repositories", find the one voted on, select and click "Release" and confirm. If successful, it
should show up under https://repository.apache.org/content/repositories/releases/org/apache/celeborn/ and the same under
https://repository.apache.org/content/groups/maven-staging-group/org/apache/celeborn/ (look for the correct release version).
After some time this will be synced to [Maven Central](https://search.maven.org/) automatically.

## Promote the release

### Update Website

Fork and clone [Apache Celeborn website](https://github.com/apache/celeborn-website).

Refer the historical release PR to update the website.

### Create an Announcement

Once everything is working, create an announcement on the website and then send an e-mail to the mailing list.
The mailing list includes: `announce@apache.org`, `dev@celeborn.apache.org`.

Note that, you must use the apache.org email to send announce to `announce@apache.org`.

Enjoy an adult beverage of your choice, and congratulations on making a Celeborn release.

## Remove the dist repo directories for deprecated release candidates

Remove the deprecated dist repo directories at last.

```shell
cd tmp/svn-dev
svn delete https://dist.apache.org/repos/dist/dev/celeborn/{RELEASE_TAG} \
  --username "${ASF_USERNAME}" \
  --password "${ASF_PASSWORD}" \
  --message "Remove deprecated Apache Celeborn ${RELEASE_TAG}" 
```
