GraphQL Flutter Freezed Classes

This project aims to speed up your development of Flutter apps by generating Freezed from your GraphQL schema.

Features

• [x] Generate Freezed classes for ObjectTypes
• [x] Generate Freezed classes for InputTypes
• [x] Support for EnumsTypes
• [x] Support for custom ScalarTypes
• [x] Support freeze documentation of class & properties from GraphQL SDL description comments
• [x] Ignore/don't generate freezed classes for certain ObjectTypes
• [] Support arguments
• [] Support directives
• [] Support deprecation annotation
• [] Support for InterfaceTypes
• [x] Support for UnionTypes union/sealed classes
• [x] Merge InputTypes with ObjectType as union/sealed class union/sealed classes

Example

Using the CLI

 ffc generate -s schema.graphql --scalars '{"jsonb": "Map<String, dynamic>","timestamptz": "DateTime", "UUID": "String"}' -m 'Create$Input' -m 'Update$Input' -m 'Upsert$Input' -m 'Delete$Input'

Given the following GraphQL schema below

# schema.graphql
type Movie {
  id: ID!
  title: String!
}

input CreateMovieInput {
  title: String!
}

input UpsertMovieInput {
  id: ID!
  title: String!
}

input UpdateMovieInput {
  id: ID!
  title: String
}

input DeleteMovieInput {
  id: ID!
}

enum Episode {
  NEWHOPE
  EMPIRE
  JEDI
}

type Starship {
  id: ID!
  name: String!
  length: Float
}

interface Character {
  id: ID!
  name: String!
  friends: [Character]
  appearsIn: [Episode]!
}

type Character {
  name: String!
  appearsIn: [Episode]!
}

type Human implements Character {
  id: ID!
  name: String!
  friends: [Character]
  appearsIn: [Episode]!
  starships: [Starship]
  totalCredits: Int
}

type Droid implements Character {
  id: ID!
  name: String!
  friends: [Character]
  appearsIn: [Episode]!
  primaryFunction: String
}

union SearchResult = Human | Droid | Starship

# tests

scalar UUID
scalar timestamptz
scalar jsonb

# cyclic references/nested types
input AInput {
  b: BInput!
}

input BInput {
  c: CInput!
}

input CInput {
  a: AInput!
}

type ComplexType {
  a: [String]
  b: [ID!]
  c: [Boolean!]!
  d: [[Int]]
  e: [[Float]!]
  f: [[String]!]!
  g: jsonb
  h: timestamptz!
  i: UUID!
}

Generated file

// app_models.dart

// with lowercaseEnums: true
enum Episode {
  @JsonKey(name: "EMPIRE") empire,
  @JsonKey(name: "JEDI") jedi,
  @JsonKey(name: "NEWHOPE") newhope,
}

// with lowercaseEnums: false
enum Gender {
  FEMALE,
  MALE,
}


@freezed
class AInput with _$AInput{
   const factory AInput({
    required BInput b
  }) = _AInput;

  factory AInput.fromJson(Map<String, dynamic> json) => _$AInputFromJson(json);
};

@freezed
class BInput with _$BInput{
   const factory BInput({
    required CInput c
  }) = _BInput;

  factory BInput.fromJson(Map<String, dynamic> json) => _$BInputFromJson(json);
};

@freezed
class CInput with _$CInput{
   const factory CInput({
    required AInput a
  }) = _CInput;

  factory CInput.fromJson(Map<String, dynamic> json) => _$CInputFromJson(json);
};

@freezed
class ComplexType with _$ComplexType{
   const factory ComplexType({
     List<String?>? a,
     List<String>? b,
    required List<bool> c,
     List<List<int?>?>? d,
     List<List<double?>>? e,
    required List<List<String?>> f,
     Map<String, dynamic>? g,
    required DateTime h,
    required String i
  }) = _ComplexType;

  factory ComplexType.fromJson(Map<String, dynamic> json) => _$ComplexTypeFromJson(json);
};

// TODO: Merge InputTypes with ObjectType as union/sealed classconst
@freezed
class Movie with _$Movie {
  const factory Movie({
    required String id,
    required String title,
  }) = _Movie;

  const factory Movie.createInput({
    required String title,
  }) = _CreateMovieInput;

  const factory Movie.upsertInput({
    required String id,
    required String title,
  }) = _UpsertMovieInput;

  const factory Movie.updateInput({
    required String id,
    String title,
  }) = _UpdateMovieInput;

  const factory Movie.deleteInput({
    required String id,
  }) = _DeleteMovieInput;

  factory Movie.fromJson(Map<String, dynamic> json) => _$MovieFromJson(json);
}

// Without mergeInputs
@freezed
class Movie with _$Movie{
  const factory Movie({
    required String id,
    required String title,
  }) = _Movie;

factory Movie.fromJson(Map<String, dynamic> json) => _$MovieFromJson(json);
}

@freezed
class CreateMovieInput with _$CreateMovieInput{
  const factory CreateMovieInput({
    required String title,
  }) = _CreateMovieInput;

factory CreateMovieInput.fromJson(Map<String, dynamic> json) => _$CreateMovieInputFromJson(json);
}

@freezed
class UpdateMovieInput with _$UpdateMovieInput{
  const factory UpdateMovieInput({
    required String id,
     String? title,
  }) = _UpdateMovieInput;

factory UpdateMovieInput.fromJson(Map<String, dynamic> json) => _$UpdateMovieInputFromJson(json);
}

@freezed
class UpsertMovieInput with _$UpsertMovieInput{
  const factory UpsertMovieInput({
    required String id,
    required String title,
  }) = _UpsertMovieInput;

factory UpsertMovieInput.fromJson(Map<String, dynamic> json) => _$UpsertMovieInputFromJson(json);
}


@freezed
class DeleteMovieInput with _$DeleteMovieInput{
  const factory DeleteMovieInput({
    required String id,
  }) = _DeleteMovieInput;

factory DeleteMovieInput.fromJson(Map<String, dynamic> json) => _$DeleteMovieInputFromJson(json);
}

Getting started

Flutter Setup

1. Install freezed in your flutter project

2. Install json_serializable in your flutter project

3. Download your GraphQL schema in graphql format and place it at the root of your Flutter project

npm install -g graphqurl

gq <graphql-endpoint>  --introspect > schema.graphql

# if your graphql endpoint requires authentication:
gq <graphql-endpoint> -H "Authorization: Bearer <token>" --introspect > schema.graphql

Generator setup

1. Install the generator globally from npm

2. Generate your Freezed classes with the CLI

CLI Usage

Description

Generate Freezed classes from your GraphQL Schema

Usage

ffc generate [-jeuEpOS -s <string> -o <string> -f <string> -i <string> -m <string> -c <string> -w <string|string[]|boolean|undefined> -T <number>]

Options

| Options | Type Definition | Default values | Description | | ---------------------------------------------------- | ------------------------- | -------------- | :------------------------------------------------------------------------------------------------------ | | -s, --schema | string | optional | the path to the GraphQL Schema. Default: ./schema.graphql | | -o, --output | string | optional | the full path of the output file. Default: ./lib/generated/app_models.dart | | -f, --fileName, --file-name | string | app_models | the name of the output file without the .dart extension. Appends/replaces the fileName in output option | | -i, --ignore, --ignoreTypes, --ignore-types | string[] | [] | names of GraphQL types to ignore when generating Freezed classes | | -j, --json, --fromJsonToJson, --from-json-to-json | boolean | true | generate fromJson and toJson methods on the classes with json_serialization | | -e, --enum, --lowercaseEnums, --lowercase-enums | boolean | true | make enum fields lowercase | | -u, --union, --unionConstructor, --union-constructor | boolean | true | generate empty constructors for Union Types | | -m, --merge, --mergeInputs, --merge-inputs | string[] | [] | merge InputTypes of a pattern with an ObjectType as a union/sealed class | | -c, --scalars, --customScalars, --custom-scalars | string | optional | a JSON.stringify object map of custom Scalars to Dart built-in types | | -w, --watch | string|string[]|boolean | optional | regenerate when GraphQL schemas changes. Accepts a boolean or an array of glob patterns | | -E, --errorsOnly, --errors-only | boolean | optional | print only errors | | -p, --usePolling, --use-polling | boolean | optional | poll for changes when watch is unavailable on system | | -T, --interval | number | optional | poll every x millisecond | | -O, --overwrite | boolean | true | overwrite files if they already exist | | -S, --silent | boolean | optional | suppress printing errors when they occur |

Contribution

What you can do to help

1. Star this repo on GitHub

2. Send in PRs

3. Share the word