Demo Create and Test ArgoCD Project

In this lesson you’ll create a new ArgoCD Project, restrict what applications in that project may do, and observe how those project-level restrictions affect application creation and synchronization. What you’ll learn

What an ArgoCD Project is and why it matters
How to restrict source repositories, cluster destinations, and Kubernetes kinds
How to create project roles and short-lived tokens
How to test a restricted project by creating and syncing an application

Relevant links and references

What is a Project?

A Project is a logical grouping of applications in ArgoCD. Projects scope what applications in that group are allowed to use — including which Git repos they can pull from, which cluster destinations and namespaces they can deploy to, and which Kubernetes API kinds they may create. Use projects to enforce team boundaries and reduce blast radius (for example, disallow non-operator teams from creating cluster-scoped resources like ClusterRole).

ArgoCD ships with a default project that is highly permissive (it can pull from any repository, deploy to any destination, and create cluster-level resources). You can modify the default project but you cannot delete it.

Default / Permissive Project Behavior

A very permissive project specification (the typical default after fresh install):

spec:
  sourceRepos:
  - '*'
  destinations:
  - namespace: '*'
    server: '*'

To allow cluster-scoped resources by default, a project can include a cluster resource allow list:

spec:
  sourceRepos:
  - '*'
  destinations:
  - namespace: '*'
    server: '*'
  clusterResourceWhitelist:
  - group: '*'
    kind: '*'

Key Project Fields (at a glance)

Field	Purpose	Example
sourceRepos	Whitelist/deny repositories the project can use	`- 'https://github.com/example/*'`
destinations	Allowed server URL and namespace pairs	`- namespace: 'default' server: 'https://kubernetes.default.svc'`
clusterResourceWhitelist / clusterResourceBlacklist	Allow or deny specific cluster-scoped API kinds	`- group: rbac.authorization.k8s.io kind: ClusterRole`
roles	Define project-level roles and policies	`argocd proj role create`

Controlling Allowed and Denied Repositories

You control repository access with sourceRepos. Patterns may be negated using a leading ! to explicitly deny matches. CLI examples to add/remove repository patterns:

argocd proj add-source <PROJECT> <REPO>
argocd proj remove-source <PROJECT> <REPO>

# To add or remove a denied (negated) source:
argocd proj add-source <PROJECT> !<REPO>
argocd proj remove-source <PROJECT> !<REPO>

Example YAML using negation patterns:

spec:
  sourceRepos:
  # Do not use the test repo in argoproj
  - '!ssh://git@github.com:argoproj/test'
  # Nor any GitLab repo under group/
  - '!https://gitlab.com/group/**'
  # Any other repo is fine though
  - '*'

Controlling Destinations and Namespaces

Destination entries define allowed (or denied) server/namespace pairs. You can negate namespace or server with a ! prefix:

spec:
  destinations:
  # Do not allow any app to be installed in `kube-system`
  - namespace: '!kube-system'
    server: '*'
  # Do not allow any cluster whose server URL matches team1-*
  - namespace: '*'
    server: '!http://team1-*'
  # Any other namespace or server is allowed
  - namespace: '*'
    server: '*'

If a project has no allowed destinations configured, application creation will fail with an InvalidSpecError.

Project Roles and Tokens

Projects can define roles and issue short-lived tokens bound to those roles. Tokens are useful for automation or cross-team access with limited scope. Typical workflow:

PROJ=myproject
APP=guestbook-default
ROLE=get-role

# Create role
argocd proj role create $PROJ $ROLE

# Create a token for the role, expires in 10 minutes
argocd proj role create-token $PROJ $ROLE -e 10m
# List and inspect role
argocd proj role list $PROJ
argocd proj role get $PROJ $ROLE

# Trying to access the app will fail until the role is granted permissions:
argocd app get $APP --auth-token $JWT

# Grant the role permission to get the specific application
argocd proj role add-policy $PROJ $ROLE --action get --permission allow --object $APP
argocd app get $APP --auth-token $JWT

# Modify policies to use a wildcard (grant access to all apps)
argocd proj role remove-policy $PROJ $ROLE -a get -o $APP
argocd proj role add-policy $PROJ $ROLE -a get --permission allow -o '*'
argocd app get $APP --auth-token $JWT

# Revoke the token when done
argocd proj role delete-token $PROJ $ROLE <token-id>
# The token no longer works:
argocd app get $APP --auth-token $JWT

Sync Windows and Global Project Mapping

Projects can be referenced by selectors and sync windows can be applied globally by mapping applications (by label selectors) to a project. Example that matches apps labeled opt: prod and maps them to proj-global-test:

- labelSelector:
    matchExpressions:
    - key: opt
      operator: In
      values:
      - prod
  projectName: proj-global-test

ConfigMap snippet that might be stored in ArgoCD settings:

data:
  globalProjects: |-
    - labelSelector:
        matchExpressions:
        - key: opt
          operator: In
          values:
          - prod
      projectName: proj-global-test
kind: ConfigMap

UI: Viewing and Editing Projects

In the ArgoCD UI navigate to Settings → Projects to view and edit projects. The UI shows project fields such as allowed source repositories, destinations, cluster resource allow/deny lists, roles, and sync windows.

A web UI screenshot of the Argo CD Projects settings page showing the "deny" project summary with general info (name "deny", 0 applications), source repositories set to "*" and no scoped repositories. The top has buttons to add roles/sync windows or delete, and a left navigation pane lists Settings, User Info and Documentation.

The UI in this environment auto-saves project edits, so you may not see an explicit “Save” button after changes.

Creating a Restricted Project (example)

We’ll create a project named deny and restrict it so users in that project cannot create ClusterRole resources. This is achieved by adding an entry to the project’s cluster resource denial list for kind ClusterRole in the rbac.authorization.k8s.io API group. Testing approach

Create or update the deny project to include a rule that denies ClusterRole.
Create an application in the deny project whose repository includes a Deployment, Service, and a ClusterRole manifest.
Attempt to sync the application and observe the sync failure caused by the denied ClusterRole.

Note: if the project does not allow your desired destination (server/namespace), application creation will fail — update the project’s destinations first, then create the app.

Create the application (CLI example)

argocd app create testing-project \
  --repo http://host.docker.internal:5000/kk-org/pod-metadata \
  --path ./manifests \
  --dest-namespace default \
  --project deny \
  --dest-server https://kubernetes.default.svc

Example repository manifest (one file under ./manifests):

apiVersion: apps/v1
kind: Deployment
metadata:
  name: highway-animation
  namespace: highway-animation
spec:
  replicas: 1
  selector:
    matchLabels:
      app: highway-animation
  template:
    metadata:
      labels:
        app: highway-animation
    spec:
      containers:
      - name: highway-animation
        image: siddharth67/highway-animation:blue
        ports:
        - containerPort: 3000
        env:
        - name: POD_COUNT
          value: "1"

If the project lacks a matching destination, you’ll see an error similar to:

{"level":"fatal","msg":"rpc error: code = InvalidArgument desc = application spec for testing-project is invalid: InvalidSpecError: application destination server 'https://kubernetes.default.svc' and namespace 'default' do not match any of the allowed destinations in project 'deny'"}

To resolve that, add an appropriate destination entry to the deny project (for testing you can allow the cluster/namespace you intend to use) and re-run the argocd app create command. Once the app is created, it will appear in the ArgoCD UI with its sync and health status.

A screenshot of the Argo CD web UI showing three application cards (app-2, highway-animation, testing-project) with status badges and Sync/Refresh/Delete buttons. The left sidebar shows navigation and filters for sync and health status.

Attempting to Synchronize the Application

Try synchronizing the testing-project application. Because the repository contains a ClusterRole manifest and the deny project blocks ClusterRole creation, synchronization will fail and the UI will indicate the blocked resource(s). When you click Synchronize in the UI, the operation will fail and report that the ClusterRole (rbac.authorization.k8s.io) is not permitted by the project’s rules.

A screenshot of the Argo CD web UI showing an application called "testing-project" marked OutOfSync on the left. The right side displays a "Synchronize" dialog with various sync options and resource checkboxes.

The sync failure details clearly show the ClusterRole was blocked by the project’s cluster resource denial list.

A screenshot of the Argo CD web UI showing an application sync that failed, with the message "one or more synchronization tasks are not valid." The result pane shows an rbac.authorization.k8s.io ClusterRole resource was blocked (not permitted) during the sync.

Because a disallowed resource prevented synchronization, the application tree will show no resources were successfully applied.

A screenshot of the Argo CD web UI showing the "testing-project" application marked OutOfSync with a "Sync failed" status. The application tree on the right lists resources like pod-metadata-service, pod-metadata-deployment, and pod-master.

Troubleshooting Tips

If application creation fails with InvalidSpecError, confirm the project’s destinations include the requested server and namespace.
If sync fails and the UI shows a blocked resource, check the project’s clusterResourceWhitelist/clusterResourceBlacklist for the resource’s API group/kind.
Use argocd proj role list and argocd proj role get to debug role and policy settings when tokens fail.

Summary

Projects let you scope repositories, cluster destinations, and permitted Kubernetes kinds for applications.
Use projects to enforce team boundaries and reduce blast radius (e.g., prevent non-operators from creating ClusterRole).
Manage projects via the CLI or UI, create project-level roles and tokens, and define sync windows and selectors for global project mapping.

That’s all for now.

ArgoCD

Argo Workflow

Argo Rollouts

Argo Events

Introduction

Demo Create and Test ArgoCD Project

What is a Project?

Default / Permissive Project Behavior

Key Project Fields (at a glance)

Controlling Allowed and Denied Repositories

Controlling Destinations and Namespaces

Project Roles and Tokens

Sync Windows and Global Project Mapping

UI: Viewing and Editing Projects

Creating a Restricted Project (example)

Create the application (CLI example)

Attempting to Synchronize the Application

Troubleshooting Tips

Summary

Watch Video

Practice Lab

​What is a Project?

​Default / Permissive Project Behavior

​Key Project Fields (at a glance)

​Controlling Allowed and Denied Repositories

​Controlling Destinations and Namespaces

​Project Roles and Tokens

​Sync Windows and Global Project Mapping

​UI: Viewing and Editing Projects

​Creating a Restricted Project (example)

​Create the application (CLI example)

​Attempting to Synchronize the Application

​Troubleshooting Tips

​Summary

Watch Video

Practice Lab

What is a Project?

Default / Permissive Project Behavior

Key Project Fields (at a glance)

Controlling Allowed and Denied Repositories

Controlling Destinations and Namespaces

Project Roles and Tokens

Sync Windows and Global Project Mapping

UI: Viewing and Editing Projects

Creating a Restricted Project (example)

Create the application (CLI example)

Attempting to Synchronize the Application

Troubleshooting Tips

Summary