Add Response.url

Closes #321, closes #623, closes #692
Fixes #293

Add a Uri field to BaseResponse with the final, potentially redirected,
url for the content.

The field is nullable for backwards compatibility - TODO: consider if
this should be non-nullable from the start, or if it can be published
nullable first and become non-nullable (and the constructor arg
required) in the next breaking release.

This may break tests which use bocks but do not mock the field used to
read the URL.

Author: natebosch

lib/src/base_request.dart

@@ -137,6 +137,7 @@ abstract class BaseRequest {
           request: response.request,
           headers: response.headers,
           isRedirect: response.isRedirect,
+          url: response.url,
           persistentConnection: response.persistentConnection,
           reasonPhrase: response.reasonPhrase);
     } catch (_) {

lib/src/base_response.dart

@@ -31,6 +31,8 @@ abstract class BaseResponse {
 
   final bool isRedirect;
 
+  final Uri? url;
+
   /// Whether the server requested that a persistent connection be maintained.
   final bool persistentConnection;
 
@@ -39,6 +41,7 @@ abstract class BaseResponse {
       this.request,
       this.headers = const {},
       this.isRedirect = false,
+      this.url,
       this.persistentConnection = true,
       this.reasonPhrase}) {
     if (statusCode < 100) {

lib/src/browser_client.dart

@@ -53,10 +53,15 @@ class BrowserClient extends BaseClient {
 
     unawaited(xhr.onLoad.first.then((_) {
       var body = (xhr.response as ByteBuffer).asUint8List();
+      var responseUrl = xhr.responseUrl;
+      var url = (responseUrl != null && responseUrl.isNotEmpty)
+          ? Uri.parse(responseUrl)
+          : null;
       completer.complete(StreamedResponse(
           ByteStream.fromBytes(body), xhr.status!,
           contentLength: body.length,
           request: request,
+          url: url,
           headers: xhr.responseHeaders,
           reasonPhrase: xhr.statusText));
     }));

lib/src/io_client.dart

@@ -59,6 +59,9 @@ class IOClient extends BaseClient {
           request: request,
           headers: headers,
           isRedirect: response.isRedirect,
+          url: response.redirects.isNotEmpty
+              ? response.redirects.last.location
+              : request.url,
           persistentConnection: response.persistentConnection,
           reasonPhrase: response.reasonPhrase,
           inner: response);

lib/src/io_streamed_response.dart

@@ -22,6 +22,7 @@ class IOStreamedResponse extends StreamedResponse {
       BaseRequest? request,
       Map<String, String> headers = const {},
       bool isRedirect = false,
+      Uri? url,
       bool persistentConnection = true,
       String? reasonPhrase,
       HttpClientResponse? inner})
@@ -31,6 +32,7 @@ class IOStreamedResponse extends StreamedResponse {
             request: request,
             headers: headers,
             isRedirect: isRedirect,
+            url: url,
             persistentConnection: persistentConnection,
             reasonPhrase: reasonPhrase);
 

lib/src/mock_client.dart

@@ -46,6 +46,7 @@ class MockClient extends BaseClient {
               request: response.request,
               headers: response.headers,
               isRedirect: response.isRedirect,
+              url: response.url,
               persistentConnection: response.persistentConnection,
               reasonPhrase: response.reasonPhrase);
         });
@@ -60,6 +61,7 @@ class MockClient extends BaseClient {
               request: response.request,
               headers: response.headers,
               isRedirect: response.isRedirect,
+              url: response.url,
               persistentConnection: response.persistentConnection,
               reasonPhrase: response.reasonPhrase);
         });

lib/src/response.dart

@@ -32,12 +32,14 @@ class Response extends BaseResponse {
       {BaseRequest? request,
       Map<String, String> headers = const {},
       bool isRedirect = false,
+      Uri? url,
       bool persistentConnection = true,
       String? reasonPhrase})
       : this.bytes(_encodingForHeaders(headers).encode(body), statusCode,
             request: request,
             headers: headers,
             isRedirect: isRedirect,
+            url: url,
             persistentConnection: persistentConnection,
             reasonPhrase: reasonPhrase);
 
@@ -46,6 +48,7 @@ class Response extends BaseResponse {
       {BaseRequest? request,
       Map<String, String> headers = const {},
       bool isRedirect = false,
+      Uri? url,
       bool persistentConnection = true,
       String? reasonPhrase})
       : bodyBytes = toUint8List(bodyBytes),
@@ -54,6 +57,7 @@ class Response extends BaseResponse {
             request: request,
             headers: headers,
             isRedirect: isRedirect,
+            url: url,
             persistentConnection: persistentConnection,
             reasonPhrase: reasonPhrase);
 

lib/src/streamed_response.dart

@@ -23,6 +23,7 @@ class StreamedResponse extends BaseResponse {
       BaseRequest? request,
       Map<String, String> headers = const {},
       bool isRedirect = false,
+      Uri? url,
       bool persistentConnection = true,
       String? reasonPhrase})
       : stream = toByteStream(stream),
@@ -31,6 +32,7 @@ class StreamedResponse extends BaseResponse {
             request: request,
             headers: headers,
             isRedirect: isRedirect,
+            url: url,
             persistentConnection: persistentConnection,
             reasonPhrase: reasonPhrase);
 }

test/io/request_test.dart

@@ -44,6 +44,7 @@ void main() {
     final response = await request.send();
 
     expect(response.statusCode, equals(302));
+    expect(response.url, serverUrl.resolve('/redirect'));
   });
 
   test('with redirects', () async {
@@ -53,6 +54,7 @@ void main() {
     expect(response.statusCode, equals(200));
     final bytesString = await response.stream.bytesToString();
     expect(bytesString, parse(containsPair('path', '/')));
+    expect(response.url, serverUrl.resolve('/'));
   });
 
   test('exceeding max redirects', () async {