Argocd Bot

A bot to help automate argo-cd changes via Github PRs.
Currently supports running diffs on open Pull Requests, check the Workflow section for more, or comment argo help on an open PR.

Benefits

Easier Deployments/Fewer Mistakes

• Comment argo diff on an open PR, to view diff between local branch and Kubernetes cluster.
• PR diffs can be easily reviewed by everyone.
• Catch errors in the output of argo diff before applying changes.
• Comment argo sync [app name] to deploy changes, and merge PR.

Lock-down Deployments

• Users can submit changes via Github (after PR approval), without needing cluster credentials.
• Audit changes made to clusters via Github PRs/server logs.

Workflow

This section describes the workflow supported by the bot.

Workflow basics

• User opens a PR in a Kubernetes repo with changes to deployment files.
• User comments with argo diff on the PR.
• Bot checks out current state of PR and runs argocd diff --local. Diff output is posted on the PR as a comment.
• Team can review code changes in the PR, and double check the posted diff.
• Author can iterate, making changes on the PR and re-comment with argo diff once they are ready.
• Deploying Changes:
  • If Auto Sync is enabled: once the PR is merged, ArgoCD server syncs it with production.
  • Otherwise, user can comment argo sync [app name] to sync changes from branch, before merging PR.

PR Example

Locking

When any command is run on by a user, the PR holds a lock, until the it is merged, or unlock is run. The PR lock prevents other users from attempting to run commands on their PRs. This is to synchronize changes on master.
i.e to prevent a scenario like this:

• Alice creates a PR, comments diff, and she's happy with the output posted.
• Bob creates a second PR, and comments diff.
• Bob merges his PR to master.
• Alice's diff output on her PR is now invalid and she might have no idea. Her merge to master, might produce a different state than what her diff had shown.

With locking in place, Bob will not be able to merge his PR until he coordinates with Alice, by either running unlock, or waiting for her PR to get merged first.

Workflow Commands

These are commands that are supported by the bot.

• argo diff: this checks out the current state of the PR, queries the argoCD server at /api/v1/applications and diffs all applications with their current state from the PR.
• argo unlock: this unlocks the current PR, so other users can run diff; see locking section above.
• argo sync [app name]: this syncs changes on current branch
• argo rollback: this rolls back latest change

More commands might be added, run argo help on a PR, to view all supported commands.

Deployment

Create a Github App

Create a new GitHub App here.

• Webhook URL, is the host where the bot will run.
• Webhook Secret, is an optional secret, make sure it matches the config (see below section)
• Private key, generate a new key and place it in the root directory, and update config below.
• Check the generated APP_ID by Github. For more on creating Github apps see

Required Permissions for Github App

Please give the argo-cd app the following permissions:

Read access to administration and metadata
Read and write access to commit statuses, issues, and pull requests 

Update Config

There is an .env_example file that should be renamed to .env. NodeJS will read that file and expose the variables to the bot, when running locally.
When running in Kubernetes, there is a helper script to create k8s secrets from that file (more on this in the kubernetes deployment section).
Here is a description of each parameter:

• PORT is the port that bot will listen on via HTTP.
• LOG_LEVEL can be set to trace, debug, info, warn, error, or fatal.
• KUBECTL_EXTERNAL_DIFF this is used by argocd diff, we pass a helper script to pretti-fy diffs posted on the PR.
• APP_ID is the app id corresponding to the Github app (this is generated on app creation).
• GHE_HOST for Github enterprise installations, specify the hostname. Otherwise leave blank, bot will use Github.com
• GITHUB_REPO this is the repo that the bot will operate on.
• GITHUB_TOKEN generate a Github token for the bot, and give it no scopes. This is just used to clone the repo.
• WEBHOOK_SECRET is the secret configured when creating the Github app (can be left empty if no secret is specified).
• PRIVATE_KEY_PATH is the path to the private key generated for the Github app, this is usually a .pem file.
• ARGOCD_SERVER, this is the ip address/hostname of the argocd server.
• ARGOCD_AUTH_TOKEN it is recommended to generate an automation token using the /api/v1/projects/{project}/roles/{role}/token API. For more information see

Kubernetes Deployment

Docker images of argocd-bot are built here, they are provided as part of releases here

Check the config section above, once you have a .env file that's populated with the correct values run ./helper_scripts/create_kubectl_secrets.sh.
This will generated a k8s secret argocd-bot-secret used by the deployment.

Build manifests using kustomize: npm run manifests

Create deployment from manifests: kubectl create -f deployment/install.yaml

Manual Deployment

See docs here

Development/Contributing

See docs here