Custom GPT Actions API with OAuth2 and Postgres

Description

Example OpenAI Custom GPT with user authentication and ability to read and write from a database.

• Database: Prisma with Neon Serverless Postgres
• Authentication: Clerk.com OAuth 2 server
• Hosting: Vercel

Getting Started

Create a Custom GPT

• Creating a GPT | OpenAI Help Center

Custom Domain Name

• you will need a custom domain name when configuring Clerk.

Setup Clerk

• create a new clerk project
• Create a production instance and assign a custom production domain
• Create a Clerk Oauth2 Provider
  • leave the callbackURL incorrect for now, we will update it later
  • update the client secret and name

curl -X POST https://api.clerk.com/v1/oauth_applications \
 -H "Authorization: Bearer <CLERK_SECRET_KEY>"  \
 -H "Content-Type: application/json" \
 -d '{"callback_url":"https://oauth-client.com/oauth2/callback", "name": "oauth_app_1", "scopes": "profile email"}'

• The response from Clerk will have the information needed to configure authentication in the custom GPT Action
• Take the Open API schema generated above, update the server addrss, and authentication endpoints, then paste it into the schema for the Action
• wait for the draft to save successfully
• refresh and you should now see the Callback URL
• Copy the Callback URL and update the Clerk Oauth2 server

curl -X PATCH https://api.clerk.com/v1/oauth_applications/<oauth_application_id> \
 -H "Authorization: Bearer <CLERK_SECRET_KEY>"  \
 -H "Content-Type: application/json" \
 -d '{"callback_url":"https://oauth-client.com/oauth2/callback"}'

Verify with:

curl -X GET https://api.clerk.com/v1/oauth_applications \
 -H "Authorization: Bearer <CLERK_SECRET_KEY>"

Setup Neon

• create a new Neon database
• update the DATABASE_URL in the .env file

Install Packages

pnpm install

Run Database Migrations

npx prisma generate npx prisma db push

Generate Open API Specs

Use the ActionsGPT created by OpenAI to create the Open API spec. https://chatgpt.com/g/g-TYEliDU6A-actionsgpt

Here is the prompt:

Create an Open API spec based on the Prisma Schema and code snippet below. OAuth2 is used for authentication. The scopes are “profile”, "email". The spec should be in YAML format. Prisma schema:

{YOUR PRISMA SCHEMA HERE}

code snippet:

{YOUR CODE HERE}

After it generates the spec, update the server URL, authorizationUrl, and tokenURL.

Deploy to Vercel

• The project is setup to deploy to Vercel without any changes.
• Note, Vercel automatically turns everything in the /api folder into serverless functions
• I suggest using the Vercel CLI to deploy the project

Update and Test the GPT

• update the Open API spec with the URL for your deployed API
• test the GPT

Privacy Policy

• Before publishing a GPT, you will need to create a privacy policy. If you don't have one, here is a prompt template:

Help me create a simple privacy policy to publish on my website for my custom GPT. My company name is [company name] and my |website is [website url]. The company will collect email addresses, but it will never sell this information to third parties Ask me any questions you need to improve the privacy policy.

Publishing a GPT

ChatGPT Domain Verification

In order to publish a GPT, you need to complete your Builder Profile including verifying your domain name. More info: https://help.openai.com/en/articles/8798878-building-and-publishing-a-gpt

FAQ

• vercel dev is not working as expected. run pnpm dev. For some reason it tries to call app.listen() a second time despite the fact that it does not do this in production.
• When deploying to vercel, there are type build errors related to Prisma.
  They are ignorable.
• How do I deploy this to a conventional Nodejs server? add a build script to package.json ("build": "tsc"). Then you can use the dist folder as the root folder for your server.
• How do I use Prisma? npx prisma generate - this will generate the Prisma client npx prisma db push - this effectively runs migrations on the Neon serverless postgres database npx prisma format - this will help define foreign keys and enforce best practices prisma migrate dev --name {name} - this will create a migration file in the migrations folder. You can use this to create a migration file. The name is the name of the migration file. The name should be in snake-case. prisma migrate deploy - this will run the migrations

Note: What I am loving about Prisma is being able to generate the Types, restart my Typescript server, and boom, I have the types for free. I can also use Prisma Studio to visually see the database schema and relationships. It's a great tool for development.

• How do I use Prisma Studio? npx prisma studio - this will open the Prisma Studio in your browser. You can use this to visually see the database schema and relationships.

Next Steps for Production Deploy

• This is a demo project. It is not recommended to deploy to a production environment. While building, I intentionally tried to keep things simple and avoid adding things like tests, error handling, and more. I did not want to make this demo too complicated. However, below are a few things I would recommend before a production deploy:
  • Add tests
  • Add error handling
  • Add more endpoints
  • Add more error handling
  • Follow this Guide on a more Vercel friendly way to organize the API endpoints into files and folders
    • https://www.prisma.io/blog/how-to-build-a-node-js-api-with-prisma-2-and-postgres-part-1-setting-up-the-development-environment-and-creating-the-database-schema
  • Alternative guide on a more standard Express structure src/ │ ├── controllers/ # Functions to handle requests │ ├── storeController.ts │ ├── productController.ts │ └── userController.ts ├── routes/ # Route definitions │ ├── storeRoutes.ts │ ├── productRoutes.ts │ └── userRoutes.ts │ └── api/ └── index.ts
  • Automatically generate Open API specs
  • consider using TSOA: https://tsoa-community.github.io/docs/getting-started.html

Contributing

PRs are welcome. Please feel free to submit a PR or an issue.

License

This project is licensed under the MIT License - see the LICENSE.txt file for details.