Google

There are three different ways to integrate Argo CD login with your Google Workspace users. Generally the OpenID Connect (oidc) method would be the recommended way of doing this integration (and easier, as well…), but depending on your needs, you may choose a different option.

• OpenID Connect using Dex
  This is the recommended login method if you don’t need information about the groups the user’s belongs to. Google doesn’t expose the groups claim via oidc, so you won’t be able to use Google Groups membership information for RBAC.
• SAML App Auth using Dex
  Dex recommends avoiding this method. Also, you won’t get Google Groups membership information through this method.
• OpenID Connect plus Google Groups using Dex
  This is the recommended method if you need to use Google Groups membership in your RBAC configuration.

Once you’ve set up one of the above integrations, be sure to edit argo-rbac-cm to configure permissions (as in the example below). See RBAC Configurations for more detailed scenarios.

apiVersion: v1
kind: ConfigMap
metadata:
  name: argocd-rbac-cm
  namespace: argocd
data:
  policy.default: role:readonly

OpenID Connect using Dex

Configure your OAuth consent screen

If you’ve never configured this, you’ll be redirected straight to this if you try to create an OAuth Client ID

1. Go to your OAuth Consent configuration. If you still haven’t created one, select Internal or External and click Create
2. Go and edit your OAuth consent screen Verify you’re in the correct project!
3. Configure a name for your login app and a user support email address
4. The app logo and filling the information links is not mandatory, but it’s a nice touch for the login page
5. In “Authorized domains” add the domains who are allowed to log in to ArgoCD (e.g. if you add example.com, all Google Workspace users with an @example.com address will be able to log in)
6. Save to continue to the “Scopes” section
7. Click on “Add or remove scopes” and add the .../auth/userinfo.profile and the openid scopes
8. Save, review the summary of your changes and finish

Configure a new OAuth Client ID

1. Go to your Google API Credentials console, and make sure you’re in the correct project.
2. Click on “+Create Credentials”/“OAuth Client ID”
3. Select “Web Application” in the Application Type drop down menu, and enter an identifying name for your app (e.g. Argo CD)
4. Fill “Authorized JavaScript origins” with your Argo CD URL, e.g. https://argocd.example.com

5. Fill “Authorized redirect URIs” with your Argo CD URL plus /api/dex/callback, e.g. https://argocd.example.com/api/dex/callback

   

6. Click “Create” and save your “Client ID” and your “Client Secret” for later

Configure Argo to use OpenID Connect

Edit argocd-cm and add the following dex.config to the data section, replacing clientID and clientSecret with the values you saved before:

data:
  url: https://argocd.example.com
  dex.config: |
    connectors:
    - config:
        issuer: https://accounts.google.com
        clientID: XXXXXXXXXXXXX.apps.googleusercontent.com
        clientSecret: XXXXXXXXXXXXX
      type: oidc
      id: google
      name: Google

References

• Dex oidc connector docs

SAML App Auth using Dex

Configure a new SAML App

Deprecation Warning

Note that, according to Dex documentation, SAML is considered unsafe and they are planning to deprecate that module.

1. In the Google admin console, open the left-side menu and select Apps > SAML Apps

   

2. Under Add App select Add custom SAML app

   

3. Enter a Name for the application (e.g. Argo CD), then choose Continue

   

4. Download the metadata or copy the SSO URL, Certificate, and optionally Entity ID from the identity provider details for use in the next section. Choose continue.

   • Base64 encode the contents of the certificate file, for example:
   • $ cat ArgoCD.cer | base64
   • Keep a copy of the encoded output to be used in the next section.
   • Ensure that the certificate is in PEM format before base64 encoding

   

5. For both the ACS URL and Entity ID, use your Argo Dex Callback URL, for example: https://argocd.example.com/api/dex/callback

   

6. Add SAML Attribute Mapping, Map Primary email to name and Primary Email to email. and click ADD MAPPING button.

   

7. Finish creating the application.

Configure Argo to use the new Google SAML App

Edit argocd-cm and add the following dex.config to the data section, replacing the caData, argocd.example.com, sso-url, and optionally google-entity-id with your values from the Google SAML App:

data:
  url: https://argocd.example.com
  dex.config: |
    connectors:
    - type: saml
      id: saml
      name: saml
      config:
        ssoURL: https://sso-url (e.g. https://accounts.google.com/o/saml2/idp?idpid=Abcde0)
        entityIssuer: https://argocd.example.com/api/dex/callback
        caData: |
          BASE64-ENCODED-CERTIFICATE-DATA
        redirectURI: https://argocd.example.com/api/dex/callback
        usernameAttr: name
        emailAttr: email
        # optional
        ssoIssuer: https://google-entity-id (e.g. https://accounts.google.com/o/saml2?idpid=Abcde0)

References

• Dex SAML connector docs
• Google’s SAML error messages

OpenID Connect plus Google Groups using Dex

We’re going to use Dex’s google connector to get additional Google Groups information from your users, allowing you to use group membership on your RBAC, i.e., giving admin role to the whole sysadmins@yourcompany.com group.

This connector uses two different credentials:

• An oidc client ID and secret
  Same as when you’re configuring an OpenID connection, this authenticates your users
• A Google service account
  This is used to connect to the Google Directory API and pull information about your user’s group membership

Also, you’ll need the email address for an admin user on this domain. Dex will impersonate that user identity to fetch user information from the API.

Configure OpenID Connect

Go through the same steps as in OpenID Connect using Dex, except for configuring argocd-cm. We’ll do that later.

Set up Directory API access

1. Follow Google instructions to create a service account with Domain-Wide Delegation
   • When assigning API scopes to the service account assign only the https://www.googleapis.com/auth/admin.directory.group.readonly scope and nothing else. If you assign any other scopes, you won’t be able to fetch information from the API
   • Create the credentials in JSON format and store them in a safe place, we’ll need them later
2. Enable the Admin SDK

Configure Dex

1. Create a secret with the contents of the previous json file encoded in base64, like this:

   apiVersion: v1
   kind: Secret
   metadata:
     name: argocd-google-groups-json
     namespace: argocd
   data:
     googleAuth.json: JSON_FILE_BASE64_ENCODED

2. Edit your argocd-dex-server deployment to mount that secret as a file

   • Add a volume mount in /spec/template/spec/containers/0/volumeMounts/ like this. Be aware of editing the running container and not the init container!

     volumeMounts:
     - mountPath: /shared
       name: static-files
     - mountPath: /tmp
       name: dexconfig
     - mountPath: /tmp/oidc
       name: google-json
       readOnly: true

   • Add a volume in /spec/template/spec/volumes/ like this:

     volumes:
     - emptyDir: {}
       name: static-files
     - emptyDir: {}
       name: dexconfig
     - name: google-json
       secret:
         defaultMode: 420
         secretName: argocd-google-groups-json

3. Edit argocd-cm and add the following dex.config to the data section, replacing clientID and clientSecret with the values you saved before, adminEmail with the address for the admin user you’re going to impersonate, and editing redirectURI with your Argo CD domain (note that the type is now google instead of oidc):

   dex.config: |
     connectors:
     - config:
         redirectURI: https://argocd.example.com/api/dex/callback
         clientID: XXXXXXXXXXXXX.apps.googleusercontent.com
         clientSecret: XXXXXXXXXXXXX
         serviceAccountFilePath: /tmp/oidc/googleAuth.json
         adminEmail: admin-email@example.com
       type: google
       id: google
       name: Google

4. Restart your argocd-dex-server deployment to be sure it’s using the latest configuration

5. Login to Argo CD and go to the “User info” section, were you should see the groups you’re member
   

6. Now you can use groups email addresses to give RBAC permissions

7. Dex (> v2.31.0) can also be configure to fetch transitive group membership as follows:

   dex.config: |
     connectors:
     - config:
         redirectURI: https://argocd.example.com/api/dex/callback
         clientID: XXXXXXXXXXXXX.apps.googleusercontent.com
         clientSecret: XXXXXXXXXXXXX
         serviceAccountFilePath: /tmp/oidc/googleAuth.json
         adminEmail: admin-email@example.com
         fetchTransitiveGroupMembership: True
       type: google
       id: google
       name: Google

References

• Dex Google connector docs