m/n/core: implement node heartbeats

This change introduces cluster member node health monitoring by
implementing a bidirectional RPC stream the nodes will periodically
send their heartbeat updates through. Management.GetNodes call was
modified to include the new node health information.

Relevant data available through the management API is non-persistent,
and stored within current Curator leader's local state. As such, it
will become briefly unavailable in an event of leader re-election. The
information returned, however, is guaranteed to be correct.

Change-Id: I916ac48f496941a7decc09d672ecf72a914b0d88
Reviewed-on: https://review.monogon.dev/c/monogon/+/694
Reviewed-by: Sergiusz Bazanski <serge@monogon.tech>
Tested-by: Jenkins CI
10 files changed
tree: 5a05f888581a3749ede7f09340119171422150e2
  1. build/
  2. intellij/
  3. metropolis/
  4. scripts/
  5. third_party/
  6. .bazelignore
  7. .bazelproject
  8. .bazelrc
  9. .git-ignore-revs
  10. .gitignore
  11. BUILD
  12. CODING_STANDARDS.md
  13. go.mod
  14. go.sum
  15. LICENSE
  16. README.md
  17. WORKSPACE
README.md

Monogon Monorepo

This is the main repository containing the source code for the Monogon Project.

This is pre-release software - feel free to look around, and check back later for our first release!

Environment

Our build environment requires a working Podman binary (your distribution should have one).

Usage

Spinning up: scripts/create_container.sh

Spinning down: scripts/destroy_container.sh

Running commands: scripts/run_in_container.sh <...>

Using bazel using a wrapper script: scripts/bin/bazel <...> (add to your local $PATH for convenience)

IntelliJ

This repository is compatible with the IntelliJ Bazel plugin, which enables full autocompletion for external dependencies and generated code. All commands run inside the container, and necessary paths are mapped into the container.

The following steps are necessary:

  • Install Google's Bazel plugin in IntelliJ. On IntelliJ 2020.3 or later, you need to install a beta release of the plugin.

  • Add the absolute path to your ~/.cache/bazel-monogon folder to your idea64.vmoptions (Help → Edit Custom VM Options) and restart IntelliJ:

    -Dbazel.bep.path=/home/leopold/.cache/bazel-monogon

  • Set "Bazel Binary Location" in Other Settings → Bazel Settings to the absolute path of scripts/bin/bazel. This is a wrapper that will execute Bazel inside the container.

  • Use File → Import Bazel project... to create a new project from .bazelproject.

After running the first sync, everything should now resolve in the IDE, including generated code.

Metropolis

Run a single node cluster

Launch the node:

scripts/bin/bazel run //:launch

Run a kubectl command:

scripts/bin/bazel run //metropolis/cli/dbg -- kubectl describe

Run tests:

scripts/bin/bazel test //...