feat: support multiple headers

analysis_options.yaml

@@ -8,16 +8,16 @@ analyzer:
 
 linter:
   rules:
-  - avoid_bool_literals_in_conditional_expressions
-  - avoid_classes_with_only_static_members
-  - avoid_private_typedef_functions
-  - avoid_returning_this
-  - avoid_unused_constructor_parameters
-  - cascade_invocations
-  - join_return_with_assignment
-  - missing_whitespace_between_adjacent_strings
-  - no_adjacent_strings_in_list
-  - no_runtimeType_toString
-  - prefer_const_declarations
-  - prefer_expression_function_bodies
-  - use_string_buffers
+    - avoid_bool_literals_in_conditional_expressions
+    - avoid_classes_with_only_static_members
+    - avoid_private_typedef_functions
+    - avoid_returning_this
+    - avoid_unused_constructor_parameters
+    - cascade_invocations
+    - join_return_with_assignment
+    - missing_whitespace_between_adjacent_strings
+    - no_adjacent_strings_in_list
+    - no_runtimeType_toString
+    - prefer_const_declarations
+    - prefer_expression_function_bodies
+    - use_string_buffers

pkgs/http/lib/http.dart

@@ -20,6 +20,7 @@ export 'src/base_response.dart';
 export 'src/byte_stream.dart';
 export 'src/client.dart' hide zoneClient;
 export 'src/exception.dart';
+export 'src/headers.dart';
 export 'src/multipart_file.dart';
 export 'src/multipart_request.dart';
 export 'src/request.dart';
@@ -34,7 +35,7 @@ export 'src/streamed_response.dart';
 /// the same server, you should use a single [Client] for all of those requests.
 ///
 /// For more fine-grained control over the request, use [Request] instead.
-Future<Response> head(Uri url, {Map<String, String>? headers}) =>
+Future<Response> head(Uri url, {Map<String, Iterable<String>>? headers}) =>
     _withClient((client) => client.head(url, headers: headers));
 
 /// Sends an HTTP GET request with the given headers to the given URL.
@@ -44,7 +45,7 @@ Future<Response> head(Uri url, {Map<String, String>? headers}) =>
 /// the same server, you should use a single [Client] for all of those requests.
 ///
 /// For more fine-grained control over the request, use [Request] instead.
-Future<Response> get(Uri url, {Map<String, String>? headers}) =>
+Future<Response> get(Uri url, {Map<String, Iterable<String>>? headers}) =>
     _withClient((client) => client.get(url, headers: headers));
 
 /// Sends an HTTP POST request with the given headers and body to the given URL.
@@ -66,7 +67,9 @@ Future<Response> get(Uri url, {Map<String, String>? headers}) =>
 /// For more fine-grained control over the request, use [Request] or
 /// [StreamedRequest] instead.
 Future<Response> post(Uri url,
-        {Map<String, String>? headers, Object? body, Encoding? encoding}) =>
+        {Map<String, Iterable<String>>? headers,
+        Object? body,
+        Encoding? encoding}) =>
     _withClient((client) =>
         client.post(url, headers: headers, body: body, encoding: encoding));
 
@@ -89,7 +92,9 @@ Future<Response> post(Uri url,
 /// For more fine-grained control over the request, use [Request] or
 /// [StreamedRequest] instead.
 Future<Response> put(Uri url,
-        {Map<String, String>? headers, Object? body, Encoding? encoding}) =>
+        {Map<String, Iterable<String>>? headers,
+        Object? body,
+        Encoding? encoding}) =>
     _withClient((client) =>
         client.put(url, headers: headers, body: body, encoding: encoding));
 
@@ -113,7 +118,9 @@ Future<Response> put(Uri url,
 /// For more fine-grained control over the request, use [Request] or
 /// [StreamedRequest] instead.
 Future<Response> patch(Uri url,
-        {Map<String, String>? headers, Object? body, Encoding? encoding}) =>
+        {Map<String, Iterable<String>>? headers,
+        Object? body,
+        Encoding? encoding}) =>
     _withClient((client) =>
         client.patch(url, headers: headers, body: body, encoding: encoding));
 
@@ -125,7 +132,9 @@ Future<Response> patch(Uri url,
 ///
 /// For more fine-grained control over the request, use [Request] instead.
 Future<Response> delete(Uri url,
-        {Map<String, String>? headers, Object? body, Encoding? encoding}) =>
+        {Map<String, Iterable<String>>? headers,
+        Object? body,
+        Encoding? encoding}) =>
     _withClient((client) =>
         client.delete(url, headers: headers, body: body, encoding: encoding));
 
@@ -141,7 +150,7 @@ Future<Response> delete(Uri url,
 ///
 /// For more fine-grained control over the request and response, use [Request]
 /// instead.
-Future<String> read(Uri url, {Map<String, String>? headers}) =>
+Future<String> read(Uri url, {Map<String, Iterable<String>>? headers}) =>
     _withClient((client) => client.read(url, headers: headers));
 
 /// Sends an HTTP GET request with the given headers to the given URL and
@@ -157,7 +166,8 @@ Future<String> read(Uri url, {Map<String, String>? headers}) =>
 ///
 /// For more fine-grained control over the request and response, use [Request]
 /// instead.
-Future<Uint8List> readBytes(Uri url, {Map<String, String>? headers}) =>
+Future<Uint8List> readBytes(Uri url,
+        {Map<String, Iterable<String>>? headers}) =>
     _withClient((client) => client.readBytes(url, headers: headers));
 
 Future<T> _withClient<T>(Future<T> Function(Client) fn) async {

pkgs/http/lib/retry.dart

@@ -136,10 +136,16 @@ final class RetryClient extends BaseClient {
     final request = StreamedRequest(original.method, original.url)
       ..contentLength = original.contentLength
       ..followRedirects = original.followRedirects
-      ..headers.addAll(original.headers)
       ..maxRedirects = original.maxRedirects
       ..persistentConnection = original.persistentConnection;
 
+    for (final (name, value) in original.headers.entries()) {
+      request.headers.append(name, value);
+    }
+    for (final cookie in original.headers.getSetCookie()) {
+      request.headers.append('set-cookie', cookie);
+    }
+
     body.listen(request.sink.add,
         onError: request.sink.addError,
         onDone: request.sink.close,

pkgs/http/lib/src/base_client.dart

@@ -9,6 +9,7 @@ import 'base_request.dart';
 import 'byte_stream.dart';
 import 'client.dart';
 import 'exception.dart';
+import 'headers.dart';
 import 'request.dart';
 import 'response.dart';
 import 'streamed_response.dart';
@@ -19,42 +20,51 @@ import 'streamed_response.dart';
 /// maybe [close], and then they get various convenience methods for free.
 abstract mixin class BaseClient implements Client {
   @override
-  Future<Response> head(Uri url, {Map<String, String>? headers}) =>
+  Future<Response> head(Uri url, {Map<String, Iterable<String>>? headers}) =>
       _sendUnstreamed('HEAD', url, headers);
 
   @override
-  Future<Response> get(Uri url, {Map<String, String>? headers}) =>
+  Future<Response> get(Uri url, {Map<String, Iterable<String>>? headers}) =>
       _sendUnstreamed('GET', url, headers);
 
   @override
   Future<Response> post(Uri url,
-          {Map<String, String>? headers, Object? body, Encoding? encoding}) =>
+          {Map<String, Iterable<String>>? headers,
+          Object? body,
+          Encoding? encoding}) =>
       _sendUnstreamed('POST', url, headers, body, encoding);
 
   @override
   Future<Response> put(Uri url,
-          {Map<String, String>? headers, Object? body, Encoding? encoding}) =>
+          {Map<String, Iterable<String>>? headers,
+          Object? body,
+          Encoding? encoding}) =>
       _sendUnstreamed('PUT', url, headers, body, encoding);
 
   @override
   Future<Response> patch(Uri url,
-          {Map<String, String>? headers, Object? body, Encoding? encoding}) =>
+          {Map<String, Iterable<String>>? headers,
+          Object? body,
+          Encoding? encoding}) =>
       _sendUnstreamed('PATCH', url, headers, body, encoding);
 
   @override
   Future<Response> delete(Uri url,
-          {Map<String, String>? headers, Object? body, Encoding? encoding}) =>
+          {Map<String, Iterable<String>>? headers,
+          Object? body,
+          Encoding? encoding}) =>
       _sendUnstreamed('DELETE', url, headers, body, encoding);
 
   @override
-  Future<String> read(Uri url, {Map<String, String>? headers}) async {
+  Future<String> read(Uri url, {Map<String, Iterable<String>>? headers}) async {
     final response = await get(url, headers: headers);
     _checkResponseSuccess(url, response);
     return response.body;
   }
 
   @override
-  Future<Uint8List> readBytes(Uri url, {Map<String, String>? headers}) async {
+  Future<Uint8List> readBytes(Uri url,
+      {Map<String, Iterable<String>>? headers}) async {
     final response = await get(url, headers: headers);
     _checkResponseSuccess(url, response);
     return response.bodyBytes;
@@ -72,11 +82,20 @@ abstract mixin class BaseClient implements Client {
 
   /// Sends a non-streaming [Request] and returns a non-streaming [Response].
   Future<Response> _sendUnstreamed(
-      String method, Uri url, Map<String, String>? headers,
+      String method, Uri url, Map<String, Iterable<String>>? headers,
       [Object? body, Encoding? encoding]) async {
     var request = Request(method, url);
 
-    if (headers != null) request.headers.addAll(headers);
+    if (headers != null) {
+      final newHeaders = Headers(headers);
+      for (final (name, value) in newHeaders.entries()) {
+        request.headers.append(name, value);
+      }
+      for (final cookie in newHeaders.getSetCookie()) {
+        request.headers.append('Set-Cookie', cookie);
+      }
+    }
+
     if (encoding != null) request.encoding = encoding;
     if (body != null) {
       if (body is String) {

pkgs/http/lib/src/base_request.dart

@@ -2,15 +2,14 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
-import 'dart:collection';
-
 import 'package:meta/meta.dart';
 
 import '../http.dart' show ClientException, get;
 import 'base_client.dart';
 import 'base_response.dart';
 import 'byte_stream.dart';
 import 'client.dart';
+import 'headers.dart';
 import 'streamed_response.dart';
 import 'utils.dart';
 
@@ -82,7 +81,7 @@ abstract class BaseRequest {
   // TODO(nweiz): automatically parse cookies from headers
 
   // TODO(nweiz): make this a HttpHeaders object
-  final Map<String, String> headers;
+  final Headers headers = Headers();
 
   /// Whether [finalize] has been called.
   bool get finalized => _finalized;
@@ -96,11 +95,7 @@ abstract class BaseRequest {
     return method;
   }
 
-  BaseRequest(String method, this.url)
-      : method = _validateMethod(method),
-        headers = LinkedHashMap(
-            equals: (key1, key2) => key1.toLowerCase() == key2.toLowerCase(),
-            hashCode: (key) => key.toLowerCase().hashCode);
+  BaseRequest(String method, this.url) : method = _validateMethod(method);
 
   /// Finalizes the HTTP request in preparation for it being sent.
   ///

pkgs/http/lib/src/base_response.dart

@@ -4,6 +4,7 @@
 
 import 'base_client.dart';
 import 'base_request.dart';
+import 'headers.dart';
 
 /// The base class for HTTP responses.
 ///
@@ -47,7 +48,7 @@ abstract class BaseResponse {
   /// by a single space. Leading and trailing whitespace in header values are
   /// always removed.
   // TODO(nweiz): make this a HttpHeaders object.
-  final Map<String, String> headers;
+  final Headers headers;
 
   final bool isRedirect;
 
@@ -57,10 +58,11 @@ abstract class BaseResponse {
   BaseResponse(this.statusCode,
       {this.contentLength,
       this.request,
-      this.headers = const {},
+      Headers? headers,
       this.isRedirect = false,
       this.persistentConnection = true,
-      this.reasonPhrase}) {
+      this.reasonPhrase})
+      : headers = headers ?? Headers() {
     if (statusCode < 100) {
       throw ArgumentError('Invalid status code $statusCode.');
     } else if (contentLength != null && contentLength! < 0) {

pkgs/http/lib/src/browser_client.dart

@@ -3,14 +3,16 @@
 // BSD-style license that can be found in the LICENSE file.
 
 import 'dart:async';
+import 'dart:convert';
 import 'dart:js_interop';
 
-import 'package:web/helpers.dart';
+import 'package:web/helpers.dart' hide Headers;
 
 import 'base_client.dart';
 import 'base_request.dart';
 import 'byte_stream.dart';
 import 'exception.dart';
+import 'headers.dart';
 import 'streamed_response.dart';
 
 final _digitRegex = RegExp(r'^\d+$');
@@ -62,14 +64,22 @@ class BrowserClient extends BaseClient {
       ..open(request.method, '${request.url}', true)
       ..responseType = 'arraybuffer'
       ..withCredentials = withCredentials;
-    for (var header in request.headers.entries) {
-      xhr.setRequestHeader(header.key, header.value);
+
+    // Sets all headers without set-cookie headers.
+    for (final (name, value) in request.headers.entries()) {
+      xhr.setRequestHeader(name, value);
+    }
+
+    // Sets cookie headers.
+    for (final cookie in request.headers.getSetCookie()) {
+      xhr.setRequestHeader('set-cookie', cookie);
     }
 
     var completer = Completer<StreamedResponse>();
 
     unawaited(xhr.onLoad.first.then((_) {
-      if (xhr.responseHeaders['content-length'] case final contentLengthHeader
+      if (xhr.responseHeaders.get('content-length')
+          case final contentLengthHeader
           when contentLengthHeader != null &&
               !_digitRegex.hasMatch(contentLengthHeader)) {
         completer.completeError(ClientException(
@@ -118,12 +128,12 @@ class BrowserClient extends BaseClient {
 }
 
 extension on XMLHttpRequest {
-  Map<String, String> get responseHeaders {
+  Headers get responseHeaders {
+    final headers = Headers();
+    final lines = const LineSplitter().convert(getAllResponseHeaders());
+
     // from Closure's goog.net.Xhrio.getResponseHeaders.
-    var headers = <String, String>{};
-    var headersString = getAllResponseHeaders();
-    var headersList = headersString.split('\r\n');
-    for (var header in headersList) {
+    for (var header in lines) {
       if (header.isEmpty) {
         continue;
       }
@@ -132,14 +142,13 @@ extension on XMLHttpRequest {
       if (splitIdx == -1) {
         continue;
       }
+
       var key = header.substring(0, splitIdx).toLowerCase();
       var value = header.substring(splitIdx + 2);
-      if (headers.containsKey(key)) {
-        headers[key] = '${headers[key]}, $value';
-      } else {
-        headers[key] = value;
-      }
+
+      headers.append(key, value);
     }
+    // return headers;
     return headers;
   }
 }