Quick Start Guide

go get github.com/graphql-go/graphql

package main

import (
    "encoding/json"
    "fmt"
    "github.com/graphql-go/graphql"
)

func main() {
    // 1. Define a simple type
    fields := graphql.Fields{
        "hello": &graphql.Field{
            Type: graphql.String,
            Resolve: func(p graphql.ResolveParams) (interface{}, error) {
                return "world", nil
            },
        },
    }
    
    // 2. Create root query type
    rootQuery := graphql.ObjectConfig{Name: "RootQuery", Fields: fields}
    
    // 3. Create schema
    schemaConfig := graphql.SchemaConfig{Query: graphql.NewObject(rootQuery)}
    schema, err := graphql.NewSchema(schemaConfig)
    if err != nil {
        panic(err)
    }

    // 4. Execute a query
    result := graphql.Do(graphql.Params{
        Schema:        schema,
        RequestString: `{ hello }`,
    })
    
    // 5. Handle results
    if result.HasErrors() {
        fmt.Printf("errors: %v\n", result.Errors)
        return
    }
    
    // 6. Output data
    json.NewEncoder(os.Stdout).Encode(result.Data)
    // Output: {"hello":"world"}
}

fields := graphql.Fields{
    "user": &graphql.Field{
        Type: graphql.String,
        Args: graphql.FieldConfigArgument{
            "id": &graphql.ArgumentConfig{
                Type: graphql.NewNonNull(graphql.String),
            },
        },
        Resolve: func(p graphql.ResolveParams) (interface{}, error) {
            id := p.Args["id"].(string)
            return fmt.Sprintf("User %s", id), nil
        },
    },
}

// Query: { user(id: "123") }

result := graphql.Do(graphql.Params{
    Schema:        schema,
    RequestString: `query GetUser($id: String!) { user(id: $id) }`,
    VariableValues: map[string]interface{}{
        "id": "123",
    },
})

import "context"

// Pass context
ctx := context.WithValue(context.Background(), "requestID", "req-123")
result := graphql.Do(graphql.Params{
    Schema:  schema,
    Context: ctx,
})

// Access in resolver
resolve: func(p graphql.ResolveParams) (interface{}, error) {
    requestID := p.Context.Value("requestID").(string)
    // Use requestID for logging, tracing, etc.
    return data, nil
}