You can connect to web applications installed on your workspace using an applications specification file located at /coder/apps/config.yaml of the workspace filesystem.

Application Launcher

Enabling workspace applications

If you'd like to use workspace applications in Coder, you can enable this feature in the UI:

  1. In the top-right, click on your avatar and select Feature Preview.
  2. Click Workspace applications and select Enable.

Application specification file

To define workspace applications, add a configuration file at /coder/apps/config.yaml to your image.

The config file specifies the parameters Coder requires to launch the application. Here is a sample config.yaml for adding a Python HTTP server as a workspace application. Note that this requires the python3 binary, which is included in Coder's base images.

# /coder/apps/config.yaml

apps:
  # Name of application in launcher. Name may consist of alphanumeric
  # characters, dashes, underscores. Names must begin with an alphanumeric
  # character. Names must be unique per application. Required.
  - name: HTTP server
    # Application scheme - must be http or https. Required.
    scheme: http
    # Application port. Required.
    port: 8000
    # Host of the application to use when dialing. Defaults to localhost.
    # Optional.
    host: "localhost"
    # Working directory for the start command. Required.
    working-directory: /home/coder
    # File path to icon used in application launcher. Icons should be either
    # PNG, SVG, or JPG. Required.
    icon-path: /home/coder/python-logo.png
    # Command to start the application. Required.
    command: python3
    # Array of arguments for command. Optional.
    args: ["-m", "http.server"]
    # Health checks to get running application status. Can use exec or http
    # health checks to localhost. Optional, but we recommend specifying a
    # health check. If you don't supply one, then an http request is sent to
    # the application root path "/".
    health-check:
      # Exec commands require an exit code of '0' to report healthy.
      exec:
        command: "pgrep"
        args: ["python3"]
      # http sends a GET request to the address specified via the parameters.
      # Expects the status codes to match; default is HTTP 200.
      http:
        # Scheme must be "http" or "https". If not specified it inherits
        # the application scheme. Optional.
        scheme: "http"
        # The host to use when dialing the address. If not specified it
        # inherits the application host. Optional.
        host: "localhost"
        # Port to use when dialing the application. If not specified it
        # inherits the application port. Optional.
        port: 8000
        # Path to use for the health check. If not specified defaults to
        # "/". Optional.
        path: ""

Notes:

  • A health check must report healthy for you to access the application.
  • If you specify both the HTTP and Exec health checks, Coder prioritizes HTTP.

Image creation

When creating your image, be sure to:

  1. In the folder where your Dockerfile is, add a coder/apps folder
  2. Add the config.yaml you created to coder/apps.
  3. Add the icon that you would like Coder to render for your app to the coder/apps folder
  4. Add a step to your Dockerfile to copy the coder folder into the image:
# copy custom apps info (config.yaml)
COPY ["./coder", "/coder"]

Sample usage

Coder offers an image that helps you set up a VNC. With a VNC available, you can add an icon to your Browser applications via setting the config file.

You are welcome to try the public Dockerfile repo that contains the example above. The repo includes config files that set up Python and Node.js HTTP servers and the accompanying icons.

You can also see our blog post for further samples on adding tools like Portainer, Insomnia, and various versions of code-server.

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