jaguar_cors #

CORS interceptor for Jaguar.dart servers

Example #

A complete example can be found here.

library main;

import 'dart:async';
import 'package:jaguar/jaguar.dart';
import 'package:jaguar_cors/jaguar_cors.dart';

static const corsOptions = const CorsOptions(
  allowedOrigins: const ['http://mine.com'],
  allowAllHeaders: true,
  allowAllMethods: true);

Cors cors(Context ctx) => new Cors(corsOptions);

@Api(path: '/api')
class Routes extends Object with CorsHelper {
  @Route(methods: const ['GET', 'OPTIONS'])
  @WrapOne(cors)
  Response<String> get(Context ctx) {
    if(ctx.req.method != 'GET') return null;
    return Response.json('Hello foreigner!');
  }

  @Route(methods: const ['POST', 'OPTIONS'])
  @WrapOne(cors)
  Future<Response<String>> post(Context ctx) async {
    if(ctx.req.method != 'POST') return null;
    return Response.json(await ctx.req.bodyAsJson());
  }
}

main() async {
  final server = new Jaguar(port: 9000);
  server.addApi(reflect(new Routes()));
  server.log.onRecord.listen(print);
  await server.serve();
}

Docs #

Configuring Cors interceptor #

CorsOptions is used to configure Cors Interceptor.

• allowedOrigins List<String>: A list of origins a cross-domain request can be executed from. Setting [allowAllOrigins] to [true] overrides [allowedOrigins] and allows all origins.
• allowAllOrigins bool: Allows all origins. If set to true, overrides allowedOrigins option.
• allowedMethods List<String>: A list of methods the client is allowed to use with cross-domain requests. Default value is simple methods (GET and POST).
• allowAllMethods bool: Allows all methods. If set to true, overrides allowedMethods option.
• allowedHeaders List<String>: A list of non simple headers the client is allowed to use with cross-domain requests.
• allowAllHeaders bool: Allows all headers. If set to true, overrides allowedHeaders option.
• exposeHeaders List<String>: Indicates which headers are safe to expose to the API of a CORS API specification
• exposeAllHeaders bool: Exposes all headers. If set to true, overrides exposeHeaders option.
• allowCredentials bool: Indicates whether the request can include user credentials like cookies, HTTP authentication or client side SSL certificates. The default is false.
• maxAge int: Indicates how long (in seconds) the results of a preflight request can be cached. The default is 0 which stands for no max age.
• vary bool:
• allowNonCorsRequests bool: Should non-CORS requests be allowed?

See API documentation for more info.

Example #

static const options = const CorsOptions(
      allowedOrigins: const ['http://mine.com'],
      // allowedHeaders: const ['X-Requested-With'],
      allowAllHeaders: true,
      allowAllMethods: true);

Wrapping the Cors interceptor #

The Cors interceptor itself is simple to use. It accepts a CorsOptions object as configuration.

Note:

1. Make sure that the route handler method/function accepts OPTIONS method.
2. If same route handler method/function is used to handle both preflight and actual route, the actual route body is skipped during preflight requests

  @Route(methods: const ['GET', 'OPTIONS'])
  @WrapOne(cors)
  Response<String> get(Context ctx) {
    if(ctx.req.method != 'GET') return null;  // Skips for preflight requests
    return Response.json('Hello foreigner!');
  }

Example #

	Cors cors(Context ctx) => new Cors(options);

  @Route(methods: const ['GET', 'OPTIONS'])
  @WrapOne(cors)
  Response<String> get(Context ctx) {
    if(ctx.req.method != 'GET') return null;
    return Response.json('Hello foreigner!');
  }