GraphQL Server Example

This example shows how to implement a GraphQL server with Golang based on Prisma & gqlgen.

How to use

1. Download example & install dependencies

Clone the repository:

git clone [email protected]:prisma/prisma-examples.git

Ensure dependencies are available and up-to-date:

cd prisma-examples/go/graphql
dep ensure -update

2. Install the Prisma CLI

To run the example, you need the Prisma CLI. Please install it via Homebrew or using another method:

brew install prisma
brew tap

3. Set up database & deploy Prisma datamodel

For this example, you'll use a free demo database (AWS Aurora) hosted in Prisma Cloud. To set up your database, run:

prisma deploy

Then, follow these steps in the interactive CLI wizard:

1. Select Demo server
2. Authenticate with Prisma Cloud in your browser (if necessary)
3. Back in your terminal, confirm all suggested values

Alternative: Run Prisma locally via Docker

1. Ensure you have Docker installed on your machine. If not, you can get it from here.
2. Create docker-compose.yml for MySQL (see here for Postgres):

   version: '3'
   services:
     prisma:
       image: prismagraphql/prisma:1.28
       restart: always
       ports:
       - "4466:4466"
       environment:
         PRISMA_CONFIG: |
           port: 4466
           databases:
             default:
               connector: mysql
               host: mysql
               port: 3306
               user: root
               password: prisma
               migrations: true
     mysql:
       image: mysql:5.7
       restart: always
       environment:
         MYSQL_ROOT_PASSWORD: prisma
       volumes:
         - mysql:/var/lib/mysql
   volumes:
     mysql:

3. Run docker-compose up -d
4. Set the endpoint in prisma.yml to http://localhost:4466
5. Run prisma deploy

4. Start the GraphQL server

go run ./server

Navigate to http://localhost:4000 in your browser to explore the API of your GraphQL server in a GraphQL Playground.

5. Using the GraphQL API

The schema that specifies the API operations of your GraphQL server is defined in ./src/schema.graphql. Below are a number of operations that you can send to the API using the GraphQL Playground.

Feel free to adjust any operation by adding or removing fields. The GraphQL Playground helps you with its auto-completion and query validation features.

Retrieve all published posts and their authors

query {
  feed {
    id
    title
    content
    published
    author {
      id
      name
      email
    }
  }
}

See more API operations

Create a new user

mutation {
  signupUser(
    name: "Sarah"
    email: "[email protected]"
  ) {
    id
  }
}

Create a new draft

mutation {
  createDraft(
    title: "Join the Prisma Slack"
    content: "https://slack.prisma.io"
    authorEmail: "[email protected]"
  ) {
    id
    published
  }
}

Publish an existing draft

mutation {
  publish(id: "__POST_ID__") {
    id
    published
  }
}

Note: You need to replace the __POST_ID__-placeholder with an actual id from a Post item. You can find one e.g. using the filterPosts-query.

Search for posts with a specific title or content

{
  filterPosts(searchString: "graphql") {
    id
    title
    content
    published 
    author {
      id
      name
      email
    }
  }
}

Retrieve a single post

{
  post(id: "__POST_ID__") {
    id
    title
    content
    published
    author {
      id
      name
      email
    }
  }
}

Note: You need to replace the __POST_ID__-placeholder with an actual id from a Post item. You can find one e.g. using the filterPosts-query.

Delete a post

mutation {
  deletePost(id: "__POST_ID__") {
    id
  }
}

Note: You need to replace the __POST_ID__-placeholder with an actual id from a Post item. You can find one e.g. using the filterPosts-query.

6. Changing the GraphQL schema

After you made changes to schema.graphql, you need to update the generated types in ./server/generated.go and potentially also adjust the resolver implementations in ./server/resolver.go:

go run sripts/gqlgen.go

This updates ./server/generated.go to incorporate the schema changes in your Go type definitions. It also generates scaffolded resolvers in tmp/resolver.go that you might need to copy and paste into ./server/resolver.go.

Next steps

• Use Prisma with an existing database
• Explore the Prisma client API
• Learn more about the GraphQL schema