Graphql on GO

gqlgen getting started

mkdir go-graphql-todoapi
cd go-graphql-todoapi

go mod init github.com/bryanpinheiro/go-graphql-todoapi

go get gorm.io/gorm
go get gorm.io/driver/sqlite

Setup gqlgen

• create a tools.go file

  //go:build tools
  // +build tools
  
  package tools
  
  import (
    _ "github.com/99designs/gqlgen"
  )

• add the dependency automatically:

  go mod tidy

Create gqlgen project structure

go run github.com/99designs/gqlgen init

Change schema.graphql and resolver.go

• schema.graphqls:

  type Todo {
      id: Int!
      title: String!
      completed: Boolean!
  }
  
  type Query {
      todo(id: Int!): Todo
  }
  
  schema {
      query: Query
  }

• resolver.go:

  package graph
  
  import (
    "context"
  
    "github.com/bryanpinheiro/go-graphql-todoapi/database"
    "github.com/bryanpinheiro/go-graphql-todoapi/models"
  )
  
  type Resolver struct{}
  
  func (r *Resolver) Todos(ctx context.Context) ([]*models.Todo, error) {
    // Access the DB instance from the database package
    db := database.DB
  
    var todos []*models.Todo
    if err := db.Find(&todos).Error; err != nil {
      return nil, err
    }
  
    return todos, nil
  }

• fix some dependencies:

  go get github.com/99designs/gqlgen/graphql/handler

Generate auto code using gqlgen

go run github.com/99designs/gqlgen generate

Run project

go run server.go