argo-cd/docs/user-guide/multiple_sources.md

Multiple Sources for an Application

!!! warning "Beta Feature" Specifying multiple sources for an application is a beta feature. The UI and CLI still generally behave as if only the first source is specified. Full UI/CLI support will be added in a future release. This feature is subject to change in backwards incompatible ways until it is marked stable.

Argo CD has the ability to specify multiple sources for a single Application. Argo CD compiles all the sources and reconciles the combined resources.

You can provide multiple sources using the sources field. When you specify the sources field, Argo CD will ignore the source (singular) field.

See the below example for specifying multiple sources:

apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: guestbook
  namespace: argocd
spec:
  project: default
  destination:
    server: https://kubernetes.default.svc
    namespace: default
  sources:
    - chart: elasticsearch
      repoURL: https://helm.elastic.co
      targetRevision: 8.5.1
    - repoURL: https://github.com/argoproj/argocd-example-apps.git
      path: guestbook
      targetRevision: HEAD

The above example has two sources specified. Argo CD will generate the manifests for each source separately and combine the resulting manifests.

!!! warning "Do not abuse multiple sources" Note that the example above is just for illustration purposes. This feature is NOT destined as a generic way to group your applications. Take a look at applicationsets and the app-of-apps pattern if you want to have a single entity for multiple applications. If you find yourself using more than 2-3 items in the sources array then you are almost certainly abusing this feature and you need to rethink your application grouping strategy.

If multiple sources produce the same resource (same group, kind, name, and namespace), the last source to produce the resource will take precedence. Argo CD will produce a RepeatedResourceWarning in this case, but it will sync the resources. This provides a convenient way to override a resource from a chart with a resource from a Git repo.

Helm value files from external Git repository

Helm sources can reference value files from git sources. This allows you to use a third-party Helm chart with custom, git-hosted values.

apiVersion: argoproj.io/v1alpha1
kind: Application
spec:
  sources:
  - repoURL: 'https://prometheus-community.github.io/helm-charts'
    chart: prometheus
    targetRevision: 15.7.1
    helm:
      valueFiles:
      - $values/charts/prometheus/values.yaml
  - repoURL: 'https://git.example.com/org/value-files.git'
    targetRevision: dev
    ref: values

In the above example, the prometheus chart will use the value file from git.example.gom/org/value-files.git. $values resolves to the root of the value-files repository. The $values variable may only be specified at the beginning of the value file path.

If the path field is set in the $values source, Argo CD will attempt to generate resources from the git repository at that URL. If the path field is not set, Argo CD will use the repository solely as a source of value files.

!!! note Sources with the ref field set must not also specify the chart field. Argo CD does not currently support using
another Helm chart as a source for value files.

!!! note Even when the ref field is configured with the path field, $value still represents the root of sources with the ref field. Consequently, valueFiles must be specified as relative paths from the root of sources.