grapher

A GraphQL field builder utilizing Go generics with extra utilities and features. Depends on graphql-go.

Examples

Without grapher

type PostsQuery struct {
	Limit int         `json:"limit"`
	Query null.String `json:"query"`
	Tags  []string    `json:"tags"`
}

type Post struct {
	ID   int    `json:"id"`
	Body string `json:"body"`
}

func buildField() graphql.Fields {
	return graphql.Fields{
		"GetPosts": &graphql.Field{
			Description : "Returns posts",
			Type: graphql.NewList(graphql.NewObject(
				graphql.ObjectConfig{
					Name:        "Post",
					Fields:      graphql.Fields{
						"id" : &graphql.Field{
							Type: graphql.Int,
						},
						"body" : &graphql.Field{
							Type: graphql.String,
						},
					},
				},
			)),
			Args: map[string]*graphql.ArgumentConfig{
				"limit": {
					Type: graphql.NewNonNull(graphql.Int),
				},
				"query": {
					Type: graphql.String,
				},
				"tags": {
					Type: graphql.NewList(graphql.String),
				},
			},
			Resolve: func(p graphql.ResolveParams) (ret interface{}, err error) {
				var q PostsQuery
				if err = mapstructure.Decode(p.Args, &q); err != nil {
					return
				}

				/// resolver logic
				return
			},
		},
	}
}

With grapher

type PostsQuery struct {
	Limit int         `json:"limit"`
	Query null.String `json:"query"`
	Tags  []string    `json:"tags"`
}

type Post struct {
	ID   int    `json:"id"`
	Body string `json:"body"`
}

func buildFieldGrapher() graphql.Fields{
	return graphql.Fields{
		"GetPosts" : grapher.NewFieldBuilder[PostsQuery, []Post]().
			WithDescription("Returns posts").
			WithResolver(func(p graphql.ResolveParams, query PostsQuery) (ret []Post, err error) {
				// resolver logic
				return 
			}).
			MustBuild(),
	}
}

v1 Development

This package is still a work-in-progress. The feature candidates for the v1 release is :

Struct to graphql.Object/graphql.InputObject translator utilizing struct tags
Struct to map[string]*graphql.ArgumentConfig{}
Configurable struct tags translator
Schema field builder utilizing go 1.18 Generics feature ensuring type safety
Resolver middlewares
Resolver arg validator
Mux-like schema building with MutationQueryCollector

Most features are done, but needs a little bit of polishing.

If you have any feature ideas, do not hesitate to tell and open a new issue in the Issues tab!

Contributing

Contributions in any way, shape, or form is super welcomed! If you have any issues, ideas or even a question just open a new issue, or make a pull request.

License

MIT

📚 grapher - Awesome Go Library for Query Language