Why am I receiving an "invalid dockerfile_path" error when building my Docker app on App Platform?

When building your Docker app on App Platform, an Invalid dockerfile_path, no such file exists in the git repository error occurs when your dockerfile_path is not correctly defined in your Application Specification (app spec) file.

By default, the dockerfile_path value is set to the file Dockerfile in the root of the repository:

name: sample-dockerfile
services:
- name: web
  git:
    repo_clone_url: https://github.com/digitalocean/sample-dockerfile.git
    branch: main
  dockerfile_path: Dockerfile

If your Dockerfile is located in a specific directory in your repository, update your app spec to use your Dockerfile’s exact location as the dockerfile_path value. To update your app spec, in the DigitalOcean Control Panel, select the app you want to update its app spec for, then click the Settings tab. In the App Spec section, click Edit, then update the app spec in the control panel:

name: sample-dockerfile
services:
- name: web
  git:
    repo_clone_url: https://github.com/digitalocean/sample-dockerfile.git
    branch: main
  dockerfile_path: <your-folder>/Dockerfile

After you’ve added the correct path to your dockerfile_path parameter, click Save to update the app spec which automatically redeploys your Docker app.

In your Dockerfile, the USER instruction needs to be after the FROM and WORKDIR instructions.
App Platform does not support 301 or 302 responses to direct traffic from one domain to another, but you can create a free blank app with a custom domain that redirects the app’s traffic to another app’s domain.