How to Scale Apps in App Platform

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.


Scaling your app allows its infrastructure to match its workload. As workloads increase and decrease, you can adjust the amount of resources necessary to keep your app running at an acceptable level of performance. For example, if your app receives a large influx of online traffic and the app’s performance becomes slow, you can increase the number of containers the app is operating in to allow more instances of the app to handle the increased workload.

You can scale the app either horizontally or vertically. Horizontally scaling the app adds additional containers to the app and the workload can be distributed across the containers. Vertical scaling increases the container’s size, providing the app with more memory and CPU resources.

Scale an App Using Automation

You can scale an app using the CLI’s app update command or API’s app update function. To scale an app, update the instance_count or instance_size_slug fields of the component in your app’s spec and then submit the new spec using either the following command or endpoint.

How to scale an app using the DigitalOcean CLI

To scale an app via the command-line, follow these steps:

  1. Install doctl, the DigitalOcean command-line tool.

  2. Create a personal access token, and save it for use with doctl.

  3. Use the token to grant doctl access to your DigitalOcean account.

                  doctl auth init
                
  4. Finally, scale an app with doctl apps update. The basic usage looks like this, but you'll want to read the usage docs for more details:

                  doctl apps update <app id> [flags]
                
How to scale an app using the DigitalOcean API

To scale an app using the DigitalOcean API, follow these steps:

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

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

    cURL

    To scale an app with cURL, call:

    
                    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"
                    },
                },
                "instance_count": 2,
                "instance_size_slug": "basic-xxs",
                "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"
                    },
                },
                "instance_count": 2,
                "instance_size_slug": "basic-xxs",
            }
        ],
        "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"
                    },
                },
            }
        ],
        "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)

Scale an App Using the Control Panel

To scale an app in the control panel, click on your app, and then click on the Settings tab.

From the Settings tab, click on the resource you’d like to scale. Scale your application horizontally by increasing the number of containers, or vertically by increasing the container size. The total cost of running a component is determined by the container size multiplied by the number of containers.

After you have selected how you want to scale the component, click Save. The app redeploys with the new scaled configuration.

Scale your app in App Platform.