How to Manage Workers in App Platform

Validated on 4 Aug 2022 • Last edited on 2 Jul 2024 build and run | buildpack | worker node

App Platform is a Platform-as-a-Service (PaaS) offering that allows developers to publish code directly to DigitalOcean servers without worrying about the underlying infrastructure.

Background workers can consist of any application code you like. As far as App Platform is concerned, they are the same as services, except they are not routable, meaning they are not accessible via an external URL.

Add a Worker to an App Using Automation

You can add a worker to an app using the CLI’s app update command or the API’s app update endpoint. To add a worker, update the app’s spec with the worker’s specifications and submit the spec using the following command or endpoint.

How to Add a Worker to an App Using the DigitalOcean CLI

Install doctl, the DigitalOcean command-line tool.
Create a personal access token and save it for use with doctl.
Use the token to grant doctl access to your DigitalOcean account.
```
          doctl auth init
          
```
Finally, run doctl apps update. Basic usage looks like this, but you can read the usage docs for more details:
```
            doctl apps update <app id> [flags]
          
```
The following example updates an app with the ID f81d4fae-7dec-11d0-a765-00a0c91e6bf6 using an app spec located in a directory called /src/your-app.yaml. Additionally, the command returns the updated app’s ID, ingress information, and creation date:
```
              doctl apps update f81d4fae-7dec-11d0-a765-00a0c91e6bf6 --spec src/your-app.yaml --format ID,DefaultIngress,Created
            
```

How to Add a Worker to an App Using the DigitalOcean API

Create a personal access token and save it for use with the API.

Send a PUT request to https://api.digitalocean.com/v2/apps/{id}

cURL

Using cURL:

                curl -X PUT \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $DIGITALOCEAN_TOKEN" \
  "https://api.digitalocean.com/v2/apps/{id}"

Python

                import os
from pydo import Client

client = Client(token=os.environ.get("DIGITALOCEAN_TOKEN"))
req = {
"spec": {
    "name": "web-app-01",
    "region": "nyc",
    "domains": [
        {
            "domain": "app.example.com",
            "type": "DEFAULT",
            "wildcard": True,
            "zone": "example.com",
            "minimum_tls_version": "1.3",
        }
    ],
    "services": [],
    "static_sites": [
        {
            "cors": {
                "allow_origins": [
                    {"exact": "https://www.example.com"},
                    {"regex": "^.*example.com"},
                ],
                "allow_methods": [
                    "GET",
                    "OPTIONS",
                    "POST",
                    "PUT",
                    "PATCH",
                    "DELETE",
                ],
                "allow_headers": ["Content-Type", "X-Custom-Header"],
                "expose_headers": ["Content-Encoding", "X-Custom-Header"],
                "max_age": "5h30m",
                "allow_credentials": False,
            },
            "routes": [{"path": "/api", "preserve_path_prefix": True}],
        }
    ],
    "jobs": [
        {
            "name": "api",
            "gitlab": {
                "branch": "main",
                "deploy_on_push": True,
                "repo": "digitalocean/sample-golang",
            },
            "image": {
                "registry": "registry.hub.docker.com",
                "registry_type": "DOCR",
                "repository": "origin/master",
                "tag": "latest",
            },
            "dockerfile_path": "path/to/Dockerfile",
            "build_command": "npm run build",
            "run_command": "bin/api",
            "source_dir": "path/to/dir",
            "envs": [
                {
                    "key": "BASE_URL",
                    "scope": "BUILD_TIME",
                    "type": "GENERAL",
                    "value": "http://example.com",
                }
            ],
            "environment_slug": "node-js",
            "log_destinations": {
                "name": "my_log_destination",
                "papertrail": {
                    "endpoint": "https://mypapertrailendpoint.com"
                },
                "datadog": {
                    "endpoint": "https://mydatadogendpoint.com",
                    "api_key": "abcdefghijklmnopqrstuvwxyz0123456789",
                },
                "logtail": {
                    "token": "abcdefghijklmnopqrstuvwxyz0123456789"
                },
               "open_search": {
                    "endpoint": "https://myopensearchendpoint.com:9300"
                    "index_name": "logs"
                    "basic_auth": {
                        "user": "doadmin",
                        "password": "password"
                    }
                },
            },
            "instance_count": 2,
            "instance_size_slug": "apps-s-1vcpu-0.5gb",
            "kind": "PRE_DEPLOY",
        }
    ],
    "workers": [
        {
            "name": "api",
            "gitlab": {
                "branch": "main",
                "deploy_on_push": True,
                "repo": "digitalocean/sample-golang",
            },
            "image": {
                "registry": "registry.hub.docker.com",
                "registry_type": "DOCR",
                "repository": "origin/master",
                "tag": "latest",
            },
            "dockerfile_path": "path/to/Dockerfile",
            "build_command": "npm run build",
            "run_command": "bin/api",
            "source_dir": "path/to/dir",
            "envs": [
                {
                    "key": "BASE_URL",
                    "scope": "BUILD_TIME",
                    "type": "GENERAL",
                    "value": "http://example.com",
                }
            ],
            "environment_slug": "node-js",
            "log_destinations": {
                "name": "my_log_destination",
                "papertrail": {
                    "endpoint": "https://mypapertrailendpoint.com"
                },
                "datadog": {
                    "endpoint": "https://mydatadogendpoint.com",
                    "api_key": "abcdefghijklmnopqrstuvwxyz0123456789",
                },
                "logtail": {
                    "token": "abcdefghijklmnopqrstuvwxyz0123456789"
                },
               "open_search": {
                    "endpoint": "https://myopensearchendpoint.com:9300"
                    "index_name": "logs"
                    "basic_auth": {
                        "user": "doadmin",
                        "password": "password"
                    }
                },
            },
            "instance_count": 2,
            "instance_size_slug": "apps-s-1vcpu-0.5gb",
        }
    ],
    "functions": [
        {
            "cors": {
                "allow_origins": [
                    {"exact": "https://www.example.com"},
                    {"regex": "^.*example.com"},
                ],
                "allow_methods": [
                    "GET",
                    "OPTIONS",
                    "POST",
                    "PUT",
                    "PATCH",
                    "DELETE",
                ],
                "allow_headers": ["Content-Type", "X-Custom-Header"],
                "expose_headers": ["Content-Encoding", "X-Custom-Header"],
                "max_age": "5h30m",
                "allow_credentials": False,
            },
            "routes": [{"path": "/api", "preserve_path_prefix": True}],
            "name": "api",
            "source_dir": "path/to/dir",
            "alerts": [
                {
                    "rule": "CPU_UTILIZATION",
                    "disabled": False,
                    "operator": "GREATER_THAN",
                    "value": 2.32,
                    "window": "FIVE_MINUTES",
                }
            ],
            "envs": [
                {
                    "key": "BASE_URL",
                    "scope": "BUILD_TIME",
                    "type": "GENERAL",
                    "value": "http://example.com",
                }
            ],
            "gitlab": {
                "branch": "main",
                "deploy_on_push": True,
                "repo": "digitalocean/sample-golang",
            },
            "log_destinations": {
                "name": "my_log_destination",
                "papertrail": {
                    "endpoint": "https://mypapertrailendpoint.com"
                },
                "datadog": {
                    "endpoint": "https://mydatadogendpoint.com",
                    "api_key": "abcdefghijklmnopqrstuvwxyz0123456789",
                },
                "logtail": {
                    "token": "abcdefghijklmnopqrstuvwxyz0123456789"
                },
               "open_search": {
                    "endpoint": "https://myopensearchendpoint.com:9300"
                    "index_name": "logs"
                    "basic_auth": {
                        "user": "doadmin",
                        "password": "password"
                    }
                },
            },
        }
    ],
    "databases": [
        {
            "cluster_name": "cluster_name",
            "db_name": "my_db",
            "db_user": "superuser",
            "engine": "PG",
            "name": "prod-db",
            "production": True,
            "version": "12",
        }
    ],
}
}
update_resp = client.apps.update(id="bb245ba", body=req)

Add a Worker Using the Control Panel

In the Apps section of the DigitalOcean Control Panel, select your app, then click the Create dropdown and choose Create Resources From Source Code to add a Worker.

Select the repository service to retrieve your source code from, either: GitHub, GitLab, DigitalOcean Container Registry, Docker Hub, or a sample app. If you are connecting to your repository from DigitalOcean for the first time, you will need to click the Manage Access button to provide DigitalOcean access to the repositories or containers, then refresh this page.
Select the repository from the Repository drop-down list. Next, select which branch of the source repo you’d like to use as the source. Optionally, for monorepos, specify the folder that contains the source in the Source Directory field. For containers, specify the image tag to use. Click Next.

App Platform will inspect the code, select an appropriate resource type and also detect any appropriate build and run commands.

To change to a different resource type, click the edit icon to open the Settings page of the resource. Click Expand next to Resource Type, choose another option from the Type drop-down list and click Save.

In the settings page, you can also change the resource’s name, view the resource’s buildpacks, edit its build and run commands, and more. Click Save to confirm your changes.

Optionally, if you want to specify additional resources, click the Add Additional Resource From Source link, repeat the procedure and click Next.
If you need to use environment variables, click Edit to the right of the resource name and supply them. Click the Encrypt checkbox to ensure a variable’s value is obscured in all build, deploy, and application logs.

To specify an app-level environment variable, click Edit to the right of Global. Click Save and then click Next.

See How to Use Environment Variables in App Platform for more details.
Review the resources, environment variables and pricing, and click Create Resources.

Edit Workers

In the Apps section of the DigitalOcean Control Panel, select your app and click on the Settings tab. Click the Worker you’d like to edit.

You can use the configuration settings you see here to change the Worker’s scaling behavior, modify environment variables, edit commands, and more.

Destroy Workers

In the Apps section of the DigitalOcean Control Panel, select your app and click on the Settings tab. Click on the Worker you’d like to destroy.

You can destroy the Worker by clicking the Destroy Component button on the bottom of the page and entering its name to confirm your selection.