How to Set Up Functions on DigitalOcean App Platform
Quick Answer
Add Functions as serverless components to an existing DigitalOcean App Platform app via Control Panel by selecting source code, configuring name/routes/envs, and deploying; structure code in packages dir for auto-detection. Use CLI/API for automation. Test via app URL with curl; troubleshoot builds by verifying source dir and specs.
Prerequisites
- DigitalOcean account with billing enabled
- Existing App Platform app or Git repository/container image
- Functions code structured in
packagesdirectory (e.g., Node.js handlers) - Repo read permissions for DigitalOcean
- Optional:
doctlCLI or API token
Step-by-Step Instructions
1
Create or Select Existing App
Ensure you have an existing app in DigitalOcean App Platform or create one via the Apps page: click Create App, select Git repository or container image source, configure resources, and deploy. Functions are serverless components auto-detected from
packages directory (e.g., packages/functions-name/index.js exporting module.exports = (event, context) => {...}).2
Navigate to App Overview
Go to the Apps page in the DigitalOcean Control Panel and select your app to open its Overview page.
3
Add Function Component
Click Add components (or Add resources). Choose Create resources from source code to add a Function, prompting the Add resources screen.
Use CLI (<code>doctl apps update</code>) or API (PUT <code>/v2/apps/{id}</code>) for automation with app spec.
4
Select Deployment Source
Choose Git repository (grant read permissions) or container image from Repository dropdown. For Git: select Branch (default:
main; enable auto-redeploy), set Source directory for monorepos (e.g., /functions). Default: root (/). App Platform auto-detects buildpacks (e.g., Node.js for <code>packages/</code>).
5
Configure Function Settings
Enter unique Name (e.g.,
api-functions). Confirm Branch and auto-redeploy. Set optional HTTP request routes (e.g., /api/*; defaults to root). Choose Instance size (default: 0.25 vCPU, 512 MiB RAM); edit for autoscaling (min:1, max:4; CPU:70%). Add Environment variables via Envs (e.g., API_KEY as SECRET, RUN_AND_BUILD_TIME). Routes determine URL: <code>app_url/component_route/package/function</code>.
6
Review and Deploy
Check Summary for config, pricing (e.g., $0.0000185/GB-s + instances), alerts (
DEPLOYMENT_FAILED, DOMAIN_FAILED). Click Add resources to deploy automatically; monitor on Overview or Activity tab.7
Verify Deployment
View live URL on Overview (e.g.,
https://your-app.ondigitalocean.app/api/endpoint). Test with curl: curl -X POST https://your-app.ondigitalocean.app/api/login \
-H "Content-Type: application/json" \
-d '{"username":"test","password":"test"}' Defaults to JSON content-type.
8
Edit Post-Deployment Settings
Go to app Settings tab, select Function, click Edit for routes, envs, or run command (e.g.,
node index.js).9
Structure Code for Detection
Organize in
packages/ dir: each subdir is a package with handler files (e.g., packages/api/index.js). Include package.json for dependencies. Supports Node.js, Python, etc. See sample repos like digitalocean/sample-functions-nodejs-qrcode.
Common Issues & Troubleshooting
Build/Deployment Failure ("DEPLOYMENT_FAILED" or "Build failed" logs)
Verify source directory (e.g., set source_dir: /functions for monorepos) and Functions structure in packages/; check build logs.
Functions not detected
Ensure code exports handlers correctly (e.g., module.exports = async (event) => {...}) in packages/ dir with package.json.
Port binding or runtime errors
Bind to 0.0.0.0 if custom; verify env vars and specs.
No auto-redeploy on Git push
Enable in branch settings; confirm repo permissions granted to DigitalOcean.
Incorrect URL/routing
Set HTTP routes (e.g., /api/*); URL follows app_url/component_route/package/function.
Prices mentioned in this guide are pulled from current plan data and may change. Always verify on the official DigitalOcean App Platform website before purchasing.