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Erlang RPM Package Agent Guide & Agents.md

Latest Erlang/OTP releases packaged as a zero dependency RPM, just enough for running RabbitMQ

ErlangRabbitMQintermediate
RabbitMQerlang-rpm
Last updated on October 28, 2024
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Instructions for AI Agents

This repository contains a zero dependency Erlang RPM package, produced and maintained by the RabbitMQ core team.

This RPM package strips off some Erlang/OTP parts that are not needed for RabbitMQ and removes the documentation that is installed on the host.

Repository Layout

  • README.md explains the goal of the project, where the dnf/yum/RPM repositories are hosted, and how this package is different from certain other Erlang RPM packages
  • Makefile is used to drive the build. It contains the package version to download and build
  • erlang.spec is the RPM spec file for building the package, including a change log section
  • otp-*.patch files are patches from the RabbitMQ team that strip some non-essential parts of Erlang/OTP and skip ddocumentation installation
  • docker/* contains various bits for building the package in containers (using Docker, Podman, and other OCI build tools)
  • docker/Dockerfile.template contains a Dockerfile template that's used to produce Dockerfiles for each supported package flavor

Artifacts

This package can be built and used on a variety of RPM-based operating systems (distributions). The names of those flavors are used in the Docker container name and resulting package filenames:

  • 9 (or stream9, or centos9) for RHEL 9.x, Rocky Linux 9.x, AlmaLinux 9.x, Oracle Linux 9.x
  • 8 (or stream8, or centos8) for RHEL 8.x, Rocky Linux 8.x, AlmaLinux 8.x, Oracle Linux 8.x
  • al2023 for Amazon Linux 2023
  • fc42 for Fedora 42, fc41 for Fedora 41, fc40 for Fedora 40, and so on

Branches

This repository has one branch per supported Erlang/OTP series:

  • erlang-28 for Erlang/OTP 28.x
  • erlang-27 for Erlang/OTP 27.x
  • erlang-26 for Erlang/OTP 26.x
  • erlang-25 for Erlang/OTP 25.x

Erlang 28.x is the most recent series.

A few more branches are exotic and exist to provide for one-off builds of this package for CentOS 7 (a long discontinued distribution):

  • erlang-27.x-centos7 for Erlang/OTP 27.x
  • erlang-26.x-centos7 for Erlang/OTP 26.x
  • erlang-25.x-centos7 for Erlang/OTP 25.x

The updates to these "CentOS 7" branches are almost always just cherry-picked version updates from erlang-27, erlang-26, and erlang-25, respectively.

Build Dependencies

This package's build infrastructure can be found under docker. It requires a Docker or Docker-compatible daemon to be installed and running.

Building OCI Images for a Specific Build Environment

docker/build-docker-image.sh is used to build the OCI for each supported flavor, for example:

bash
# build an OCI image for building the package for the RHEL 9/CentOS Stream9/Rocky Linux 9/AlmaLinux 9/Oracle Linux 9 family
docker/build-docker-image.sh 9
bash
# build an OCI image for building the package for the RHEL 8/CentOS Stream8/Rocky Linux 8/AlmaLinux 8/Oracle Linux 8 family
docker/build-docker-image.sh 8
bash
# build an OCI image for building the package for Fedora 42
docker/build-docker-image.sh fc42

# build an OCI image for building the package for Fedora 41
docker/build-docker-image.sh fc41
bash
# build an OCI image for Amazon Linux 2023
docker/build-docker-image.sh al2023

Building a Package in Specific Build Environments

docker/build-package.sh is used to build the package for each supported flavor, for example:

bash
# build the package for the RHEL 9/CentOS Stream9/Rocky Linux 9/AlmaLinux 9/Oracle Linux 9 family
docker/build-package.sh 9
bash
# build the package for the RHEL 8/CentOS Stream8/Rocky Linux 8/AlmaLinux 8/Oracle Linux 8 family
docker/build-package.sh 8
bash
# build the package for Fedora 42
docker/build-package.sh fc42

# build the package for Fedora 41
docker/build-package.sh fc41
bash
# build the package for Amazon Linux 2023
docker/build-package.sh al2023

Other Build Directories

  • docker/pkg-build-dir is a top-level directory used by docker/build-package.sh, rpmbuild, and other tools involved
  • docker/all_rpms stores the final build artifacts: the RPM files

Build Infrastructure

The build infrastructure (GitHub Actions) that produces the artifacts using the templates and scripts under docker are hosted in a separate repository, rabbitmq/erlang-packages.

Updating for New Releases

When asked to update the package for a new Erlang/OTP release to a specific version, or told that a new Erlang/OTP release is available,

  • Determine what series a new release belongs to and switch to the corresponding branch. For example, 28.0.3 belongs to the 28 series and should be done on the erlang-28 branch; 27.4.3.3 belongs to the Erlang 27 series and should be done on the erlang-27 branch; and so on
  • Update the version in Makefile
  • Update the version (the package_ver and upstream_ver global variables) and the change log section in erlang.spec
  • Use commit 4571febb4b22a9f36cc302bcd46a1aaf08670433 as an example

Backporting

When asked to backport a change, always use the -x command line flag with git cherry-pick.

Committing Changes

When committing changes to the repository, never add yourself as an author, a co-author, or a committer.

Never push your changes unless explicitly asked to do so. Let a human review them and push.

Metadata: Updating AGENTS.md, GEMINI.md, CLAUDE.md

When updating AGENTS.md, GEMINI.md and CLAUDE.md, treat AGENTS.md as the primary instructions file, and GEMINI.md, CLAUDE.md as copies (technically, symlinks).

Treat the branch for the most recent series (covered above) as the source of truth.

AGENTS.md, GEMINI.md, CLAUDE.md are collectively called the "agent instruction files".