ArgoCD - When deploying one app in monorepo with multiple application, all app re-sync triggers

Question

All ! :)

I’m using the mono-repo with multi application architecture.

- foo
  - dev
  - alp
  - prd
- bar
  - dev
  - alp
  - prd
- argocd
  - dev
    - foo-application (argo cd app, target revision : master, destination cluster : dev, path: foo/dev)
    - bar-application (argo cd app, target revision : master, destination cluster : dev, path: bar/dev)
  - alp
    - foo-application (argo cd app, target revision : master, destination cluster: alp, path: foo/alp)
    - bar-application (argo cd app, target revision : master, destination cluster: alp, path: bar/alp)
  - ...

Recently I found out that merging to the master branch triggers syncing with other applications as well Despite no change in that target path directory..

So, whenever one application is modified and merged into the master, multiple applications are Out-Of-Sync -> Syncing -> Synced is happening repeatedly. :(

In my opinion, if there is no code change in the target path, even if the git sha value of the branch changes, synced is maintained.

But it wasn’t. When the git sha of the target branch is changed, ArgoCD is unconditionally triggered by changing the cache key.

To solve this problem, it seems wasteful to create a manifest repository for each application.

While looking for a solution, I came across this feature.

webhook-and-manifest-paths-annotation

However, according to the documentation, this seems to work when used with the GitHub Webhook.

Currently we are using ArgoCD polling the Repository every 3 minutes. Does this annotation not work in this case?

Answer 1

Yes, the manifest-generate-paths annotation only works with webhooks. However, take a look at this: https://argo-cd.readthedocs.io/en/stable/user-guide/sync-options/#selective-sync

If you add this to your app's syncPolicy:

    syncOptions:
    - ApplyOutOfSyncOnly=true

Argo will only sync resources when their manifest has changed