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Argo CD

Argo CD

Argo CD does not interpret arbitrary custom-resource status. Unknown CRDs are reported Healthy as soon as they exist, so a DiscoveryPolicy that is failing to reach its registry, or a CachedImage still pulling, would show green.

drop already exposes the idiomatic Kubernetes status shape — status.phase and status.conditions[] with a Ready condition — but Argo CD needs a small Lua health check to translate it. Install the checks below to get real health in the Argo CD UI, accurate Application health, and the ability to gate sync waves on CachedImage/CachedImageSet readiness.

Status drop exposes

Kindstatus.phaseReady conditionNotes
CachedImagePending | Pulling | Ready | Degradedyes (reason/message)status.ready is a nodesReady/nodesTargeted string
CachedImageSetPending | Ready | Degradedyesaggregates child CachedImages
DiscoveryPolicy—yes (Synced / error reason)no phase; health comes from the Ready condition
PullPolicy——config-only, no status → always Healthy

Health checks

Add the following to the argocd-cm ConfigMap in the Argo CD install namespace. The keys use the standard resource.customizations.health.<group>_<kind> form.

apiVersion: v1
kind: ConfigMap
metadata:
  name: argocd-cm
  namespace: argocd
  labels:
    app.kubernetes.io/name: argocd-cm
    app.kubernetes.io/part-of: argocd
data:
  # CachedImage: gate on phase, fall back to the Ready condition.
  resource.customizations.health.drop.corewire.io_CachedImage: |
    hs = {}
    if obj.status == nil then
      return { status = "Progressing", message = "Waiting for status" }
    end
    -- Wait for the controller to observe the latest spec.
    if obj.metadata.generation ~= nil and obj.status.observedGeneration ~= nil
       and obj.status.observedGeneration < obj.metadata.generation then
      return { status = "Progressing", message = "Reconciling" }
    end
    local msg = obj.status.ready or ""
    if obj.status.conditions ~= nil then
      for _, c in ipairs(obj.status.conditions) do
        if c.type == "Ready" and c.message ~= nil and c.message ~= "" then
          msg = c.message
        end
      end
    end
    if obj.status.phase == "Ready" then
      return { status = "Healthy", message = msg }
    end
    if obj.status.phase == "Degraded" then
      return { status = "Degraded", message = msg }
    end
    -- Pending / Pulling / empty
    return { status = "Progressing", message = msg }

  # CachedImageSet: same shape, phase is Pending | Ready | Degraded.
  resource.customizations.health.drop.corewire.io_CachedImageSet: |
    if obj.status == nil then
      return { status = "Progressing", message = "Waiting for status" }
    end
    if obj.metadata.generation ~= nil and obj.status.observedGeneration ~= nil
       and obj.status.observedGeneration < obj.metadata.generation then
      return { status = "Progressing", message = "Reconciling" }
    end
    local managed = obj.status.imagesManaged or 0
    local ready = obj.status.imagesReady or 0
    local msg = tostring(ready) .. "/" .. tostring(managed) .. " images ready"
    if obj.status.conditions ~= nil then
      for _, c in ipairs(obj.status.conditions) do
        if c.type == "Ready" and c.message ~= nil and c.message ~= "" then
          msg = c.message
        end
      end
    end
    if obj.status.phase == "Ready" then
      return { status = "Healthy", message = msg }
    end
    if obj.status.phase == "Degraded" then
      return { status = "Degraded", message = msg }
    end
    return { status = "Progressing", message = msg }

  # DiscoveryPolicy: no phase — health is the Ready condition.
  resource.customizations.health.drop.corewire.io_DiscoveryPolicy: |
    if obj.status == nil or obj.status.conditions == nil then
      return { status = "Progressing", message = "Waiting for first sync" }
    end
    if obj.metadata.generation ~= nil and obj.status.observedGeneration ~= nil
       and obj.status.observedGeneration < obj.metadata.generation then
      return { status = "Progressing", message = "Reconciling" }
    end
    for _, c in ipairs(obj.status.conditions) do
      if c.type == "Ready" then
        if c.status == "True" then
          return { status = "Healthy", message = c.message }
        end
        return { status = "Degraded", message = c.message }
      end
    end
    return { status = "Progressing", message = "No Ready condition yet" }

  # PullPolicy: configuration-only, no status.
  resource.customizations.health.drop.corewire.io_PullPolicy: |
    return { status = "Healthy", message = "Configuration resource" }

If your Argo CD version prefers the list-based form, the same logic can be placed under the resourceHealthChecks key instead — one entry per group/kind.

Applying it

  • Argo CD Helm chart / Kustomize install: set these under configs.cm (resource.customizations.health.*) in your Argo CD values, or patch the argocd-cm ConfigMap. Health checks are a cluster-wide Argo CD setting — they are read from argocd-cm and apply to every Application and AppProject; Argo CD has no per-Application or per-AppProject health-check override.
  • Reload: argocd-cm is picked up automatically; no restart is required.

Sync waves

Because the checks report Progressing until a resource is actually Ready, you can make a later sync wave wait for caching to finish. For example, keep the drop operator on an earlier wave and place CachedImageSet resources on a later wave; Argo CD will hold the wave until the sets report Healthy.

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