Retrofit For Dart

retrofit.dart is a type conversion dio client generator using source_gen and inspired by Chopper and Retrofit.

Usage

Generator

Add the generator to your dev dependencies

dependencies:
  retrofit: any
  logger: any  #for logging purpose

dev_dependencies:
  retrofit_generator: any
  build_runner: any

Define and Generate your API

import 'package:json_annotation/json_annotation.dart';
import 'package:retrofit/retrofit.dart';
import 'package:dio/dio.dart';

part 'example.g.dart';

@RestApi(baseUrl: "https://5d42a6e2bc64f90014a56ca0.mockapi.io/api/v1/")
abstract class RestClient {
  factory RestClient(Dio dio, {String baseUrl}) = _RestClient;

  @GET("/tasks")
  Future<List<Task>> getTasks();
}

@JsonSerializable()
class Task {
  String id;
  String name;
  String avatar;
  String createdAt;

  Task({this.id, this.name, this.avatar, this.createdAt});

  factory Task.fromJson(Map<String, dynamic> json) => _$TaskFromJson(json);
  Map<String, dynamic> toJson() => _$TaskToJson(this);
}

then run the generator

# dart
pub run build_runner build

# flutter	
flutter pub run build_runner build

Use it

import 'package:logger/logger.dart';
import 'package:retrofit_example/example.dart';
import 'package:dio/dio.dart';

final logger = Logger();
void main(List<String> args) {
  final dio = Dio();   // Provide a dio instance
  dio.options.headers["Demo-Header"] = "demo header";   // config your dio headers globally
  final client = RestClient(dio);
  
  client.getTasks().then((it) => logger.i(it));

Type Conversion

Before you use the type conversion, please make sure that a factory Task.fromJson(Map<String, dynamic> json) must be provided for each model class. json_serializable is the recommanded to be used as the serialization tool.

...
@GET("/tasks")
  Future<List<Task>> getTasks();
}

@JsonSerializable()
class Task {
  String name;
  Task({this.name});
  factory Task.fromJson(Map<String, dynamic> json) => _$TaskFromJson(json);
}

HTTP Methods

The HTTP methods in the below sample are supported.

  @GET("/tasks/{id}")
  Future<Task> getTask(@Path("id") String id);

  @GET('/demo')
  Future<String> queries(@Queries() Map<String, dynamic> queries);

  @GET("https://httpbin.org/get")
  Future<String> namedExample(
      @Query("apikey") String apiKey,
      @Query("scope") String scope, 
      @Query("type") String type,
      @Query("from") int from
  );

  @PATCH("/tasks/{id}")
  Future<Task> updateTaskPart(
      @Path() String id, @Body() Map<String, dynamic> map);

  @PUT("/tasks/{id}")
  Future<Task> updateTask(@Path() String id, @Body() Task task);

  @DELETE("/tasks/{id}")
  Future<void> deleteTask(@Path() String id);

  @POST("/tasks")
  Future<Task> createTask(@Body() Task task);

  @POST("http://httpbin.org/post")
  Future<void> createNewTaskFromFile(@Part() File file);

  @POST("http://httpbin.org/post")
  @FormUrlEncoded()
  Future<String> postUrlEncodedFormData(@Field() String hello);

Get orignal HTTP reponse

  @GET("/tasks/{id}")
  Future<HttpResponse<Task>> getTask(@Path("id") String id)

  @GET("/tasks")
  Future<HttpResponse<List<Task>>>> getTasks()

HTTP Header

Add a HTTP header from the parameter of the method

	@GET("/tasks")
  Future<Task> getTasks(@Header("Content-Type") String contentType );

Add staitc HTTP headers

	@GET("/tasks")
	@Headers(<String, dynamic>{
		"Content-Type" : "application/json",
		"Custom-Header" : "Your header"
	})
  Future<Task> getTasks();

Error Handling

catchError(Object) should be used for capturing the exception and failed response. You can get the detailed response info from DioError.response.

 client.getTask("2").then((it){
   logger.i(it);
 }).catchError((Object obj) {
    // non-200 error goes here.
    switch (obj.runtimeType) {
      case DioError:
        // Here's the sample to get the failed response error code and message
        final res = (obj as DioError).response;
        logger.e("Got error : ${res.statusCode} -> ${res.statusMessage}");
        break;
      default:
    }
  });

}

Multiple endpoints support

If you want to use multiple endpoints to your RestClient, you should pass your base url when you initiate RestClient. Any value defined in RestApi will be ignored.

@RestApi(baseUrl: "this url will be ignored if baseUrl is passed")
abstract class RestClient {
  factory RestClient(Dio dio, {String baseUrl}) = _RestClient;
}

final client = RestClient(dio, baseUrl: "your base url");

If you want to use the base url from dio.option.baseUrl, which has lowest priority, please don't pass any parameter to RestApi annotation and RestClient's structure method.

Hide generated files

For the project not to be confused with the files generated by the retrofit you can hide them.

Android studio

File -> Settings -> Editor -> File Types

Add "ignore files and folders"

*.g.dart

SBNTT / retrofit.dart