No release in over 3 years
Low commit activity in last 3 years
Generates swift code based on the GraphQL schema to provide type-safe API for building GraphQL queries and using their responses.
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
 Dependencies

Development

~> 1.13
~> 1.3
~> 5.10
~> 12.0

Runtime

 Project Readme

GraphQLSwiftGen

Build Status

Generate swift code for any specific GraphQL schema that provides query builders and response classes.

Installation

The code generator requires ruby version 2.1 or later.

Until this project is released, it is recommended to include it into a project as a git submodule.

$ git submodule https://github.com/Shopify/graphql_swift_gen.git

It is recommended to use bundler to install the code generators ruby package.

Add this line to your application's Gemfile:

gem 'graphql_swift_gen', path: 'graphql_swift_gen'

And then execute:

$ bundle

The generated code depends on support/Sources/GraphQL.swift from this repo which should be added to the project along with the generated code.

Usage

Create a script that generates the code for a GraphQL API

require 'graphql_swift_gen'
require 'graphql_schema'
require 'json'

introspection_result = File.read("graphql_schema.json")
schema = GraphQLSchema.new(JSON.parse(introspection_result))

GraphQLSwiftGen.new(schema,
  nest_under: 'ExampleSchema',
  custom_scalars: [
    GraphQLSwiftGen::Scalar.new(
      type_name: 'Money',
      swift_type: 'NSDecimalNumber',
      deserialize_expr: ->(expr) { "NSDecimalNumber(string: #{expr}, locale: GraphQL.posixLocale)" },
      serialize_expr: ->(expr) { "#{expr}.description(withLocale: GraphQL.posixLocale)" },
    ),
  ]
).save("#{Dir.pwd}/../MyApp/Source")

That generated code depends on the GraphQLSupport package.

The generated code includes a query builder that can be used to create a GraphQL query in a type-safe mannar.

let queryString = ExampleSchema.buildQuery { $0
    .user { $0
        .firstName()
        .lastName()
    }
}

The generated code also includes response classes that will deserialize the response and provide methods for accessing the field data with it already coerced to the correct type.

guard let response = try? GraphQLResponse<ExampleSchema.QueryRoot>(jsonData: response) else {
    print("Invalid GraphQL response")
    return
}
if let errors = response.errors {
    for error in errors {
        print("GraphQL error: \(error.message)")
    }
}
if let data = response.data {
    let user = data.user
    print("\(user.firstName) \(user.lastName)")
}

Development

After checking out the repo, run bundle to install ruby dependencies. Then, run rake test to run the tests.

To install this gem onto your local machine, run bundle exec rake install or reference it from a Gemfile using the path option (e.g. gem 'graphql_swift_gen', path: '~/src/graphql_swift_gen').

Contributing

See our contributing guidelines for more information.

License

The gem is available as open source under the terms of the MIT License.