GraphQL for .NET

This is an implementation of Facebook's GraphQL in .NET.

This project uses a lexer/parser originally written by Marek Magdziak and released with a MIT license. Thank you Marek!

Installation

You can install the latest version via NuGet.

PM> Install-Package GraphQL

Documentation

http://graphql-dotnet.github.io

Examples

https://github.com/graphql-dotnet/examples

Training

• API Development in .NET with GraphQL - Glenn Block demonstrates how to use the GraphQL .NET framework to build a fully functional GraphQL endpoint.

Upgrade Guides

• 0.17.x to 2.x
• 0.11.0
• 0.8.0

Basic Usage

Define your schema with a top level query object then execute that query.

Fully-featured examples can be found here.

Hello World

var schema = Schema.For(@"
  type Query {
    hello: String
  }
");

var root = new { Hello = "Hello World!" };
var json = schema.Execute(_ =>
{
  _.Query = "{ hello }";
  _.Root = root;
});

Console.WriteLine(json);

Schema First Approach

This example uses the Graphql schema language. See the documentation for more examples and information.

public class Droid
{
  public string Id { get; set; }
  public string Name { get; set; }
}

public class Query
{
  [GraphQLMetadata("droid")]
  public Droid GetDroid()
  {
    return new Droid { Id = "123", Name = "R2-D2" };
  }
}

var schema = Schema.For(@"
  type Droid {
    id: ID
    name: String
  }

  type Query {
    droid: Droid
  }
", _ => {
    _.Types.Include<Query>();
});

var json = schema.Execute(_ =>
{
  _.Query = "{ droid { id name } }";
});

Parameters

public class Droid
{
  public string Id { get; set; }
  public string Name { get; set; }
}

public class Query
{
  private List<Droid> _droids = new List<Droid>
  {
    new Droid { Id = "123", Name = "R2-D2" }
  };

  [GraphQLMetadata("droid")]
  public Droid GetDroid(string id)
  {
    return _droids.FirstOrDefault(x => x.Id == id);
  }
}

var schema = Schema.For(@"
  type Droid {
    id: ID
    name: String
  }

  type Query {
    droid(id: ID): Droid
  }
", _ => {
    _.Types.Include<Query>();
});

var json = schema.Execute(_ =>
{
  _.Query = $"{{ droid(id: \"123\") {{ id name }} }}";
});

Roadmap

Grammar / AST

• Grammar and AST for the GraphQL language should be compatible with the June 2018 specification.

Operation Execution

• Scalars
• Objects
• Lists of objects/interfaces
• Interfaces
• Unions
• Arguments
• Variables
• Fragments
• Directives
  • Include
  • Skip
  • Custom
• Enumerations
• Input Objects
• Mutations
• Subscriptions
• Async execution

Validation

• Arguments of correct type
• Default values of correct type
• Fields on correct type
• Fragments on composite types
• Known argument names
• Known directives
• Known fragment names
• Known type names
• Lone anonymous operations
• No fragment cycles
• No undefined variables
• No unused fragments
• No unused variables
• Overlapping fields can be merged (help with this rule)
• Possible fragment spreads
• Provide non-null arguments
• Scalar leafs
• Unique argument names
• Unique directives per location
• Unique fragment names
• Unique input field names
• Unique operation names
• Unique variable names
• Variables are input types
• Variables in allowed position

Schema Introspection

• __typename
• __type
  • name
  • kind
  • description
  • fields
  • interfaces
  • possibleTypes
  • enumValues
  • inputFields
  • ofType
• __schema
  • types
  • queryType
  • mutationType
  • subscriptionType
  • directives

Publishing Nugets

yarn run setVersion 2.0.0
git commit/push
download nuget from AppVeyor
upload nuget package to github
publish nuget from MyGet

Running on OSX with mono

To run this project on OSX with mono you will need to add some configuration. Make sure mono is installed and add the following to your bash configuration:

export FrameworkPathOverride=/Library/Frameworks/Mono.framework/Versions/4.6.2/lib/mono/4.5/

See the following for more details:

• Building VS 2017 MSBuild csproj Projects with Mono on Linux
• using .NET Framework as targets framework, the osx/unix build fails