1. update deps

2. support range fetch when retry
3. add skipRetryStatusCode, fix #107

Author: mchome

example/lib/main.dart

@@ -88,7 +88,7 @@ class LoadImage extends StatelessWidget {
             color: Colors.transparent,
             child: const Icon(Icons.refresh),
           ),
-          imageFilter: ImageFilter.blur(sigmaX: 10.0, sigmaY: 10.0),
+          // imageFilter: ImageFilter.blur(sigmaX: 10.0, sigmaY: 10.0),
           width: 300.0,
           height: 300.0,
           enableRefresh: true,

lib/src/provider/flutter_advanced_networkimage.dart

@@ -36,6 +36,7 @@ class AdvancedNetworkImage extends ImageProvider<AdvancedNetworkImage> {
     this.postProcessing,
     this.disableMemoryCache: false,
     this.printError = false,
+    this.skipRetryStatusCode,
   })  : assert(url != null),
         assert(scale != null),
         assert(useDiskCache != null),
@@ -118,6 +119,9 @@ class AdvancedNetworkImage extends ImageProvider<AdvancedNetworkImage> {
   /// Print error messages.
   final bool printError;
 
+  /// The [HttpStatus] code that you can skip retrying if you meet them.
+  final List<int> skipRetryStatusCode;
+
   ImageStream resolve(ImageConfiguration configuration) {
     assert(configuration != null);
     final ImageStream stream = ImageStream();
@@ -262,6 +266,7 @@ Future<Uint8List> _loadFromDiskCache(
       key.timeoutDuration,
       key.loadingProgress,
       key.getRealUrl,
+      skipRetryStatusCode: key.skipRetryStatusCode,
       printError: key.printError,
     );
     if (imageData != null) {

lib/src/provider/flutter_advanced_networksvg.dart

@@ -33,6 +33,7 @@ class AdvancedNetworkSvg extends PictureProvider<AdvancedNetworkSvg> {
     this.cacheRule,
     this.getRealUrl,
     this.printError = false,
+    this.skipRetryStatusCode,
   })  : assert(url != null),
         assert(scale != null),
         assert(useDiskCache != null),
@@ -89,9 +90,12 @@ class AdvancedNetworkSvg extends PictureProvider<AdvancedNetworkSvg> {
   /// Extract the real url before fetching.
   final UrlResolver getRealUrl;
 
-  /// Print error.
+  /// Print error messages.
   final bool printError;
 
+  /// The [HttpStatus] code that you can skip retrying if you meet them.
+  final List<int> skipRetryStatusCode;
+
   @override
   Future<AdvancedNetworkSvg> obtainKey(PictureConfiguration picture) {
     return SynchronousFuture<AdvancedNetworkSvg>(this);
@@ -222,6 +226,7 @@ Future<Uint8List> _loadFromDiskCache(AdvancedNetworkSvg key, String uId) async {
       key.timeoutDuration,
       null,
       key.getRealUrl,
+      skipRetryStatusCode: key.skipRetryStatusCode,
       printError: key.printError,
     );
     if (imageData != null) {

lib/src/utils.dart

@@ -304,25 +304,32 @@ Future<Uint8List> loadFromRemote(
   Duration timeoutDuration,
   LoadingProgress loadingProgress,
   UrlResolver getRealUrl, {
+  List<int> skipRetryStatusCode,
   bool printError = false,
 }) async {
   assert(url != null);
   assert(retryLimit != null);
 
   if (retryLimit < 0) retryLimit = 0;
+  skipRetryStatusCode ??= [];
 
   /// Retry mechanism.
   Future<http.Response> run<T>(Future f(), int retryLimit,
       Duration retryDuration, double retryDurationFactor) async {
     for (int t in List.generate(retryLimit + 1, (int t) => t + 1)) {
       try {
         http.Response res = await f();
-        if (res != null && res.bodyBytes.length > 0) {
-          if (res.statusCode == HttpStatus.ok)
+        if (res != null) {
+          if ([HttpStatus.ok, HttpStatus.partialContent]
+                  .contains(res.statusCode) &&
+              res.bodyBytes.length > 0) {
             return res;
-          else if (printError)
-            debugPrint('Load error, response status code: ' +
-                res.statusCode.toString());
+          } else {
+            if (printError)
+              debugPrint(
+                  'Failed to load, response status code: ${res.statusCode.toString()}.');
+            if (skipRetryStatusCode.contains(res.statusCode)) return null;
+          }
         }
       } catch (e) {
         if (printError) debugPrint(e.toString());
@@ -334,6 +341,9 @@ Future<Uint8List> loadFromRemote(
     return null;
   }
 
+  List<int> buffer = [];
+  bool acceptRangesHeader = false;
+
   http.Response _response;
   _response = await run(() async {
     String _url = url;
@@ -342,8 +352,13 @@ Future<Uint8List> loadFromRemote(
     if (loadingProgress != null) {
       final _req = http.Request('GET', Uri.parse(_url));
       _req.headers.addAll(header ?? {});
+      if (!acceptRangesHeader)
+        _req.headers[HttpHeaders.rangeHeader] = 'bytes=${buffer.length}-';
       final _res = await _req.send().timeout(timeoutDuration);
-      List<int> buffer = [];
+      acceptRangesHeader =
+          _res.headers.containsKey(HttpHeaders.acceptRangesHeader) &&
+              _res.headers[HttpHeaders.acceptRangesHeader] == 'bytes';
+      if (!acceptRangesHeader) buffer.clear();
       final Completer<http.Response> completer = Completer<http.Response>();
       _res.stream.listen(
         (bytes) {

pubspec.yaml

@@ -1,22 +1,22 @@
 name: flutter_advanced_networkimage
 description: An advanced image provider provides caching and retrying for flutter app. Now with zoomable widget and transition to image widget.
-version: 0.5.0
+version: 0.5.1
 author: "fuyumi <[email protected]>"
 homepage: https://github.com/mchome/flutter_advanced_networkimage
 
 dependencies:
   flutter:
     sdk: flutter
-  http: "^0.12.0"
-  path_provider: "^1.1.0"
-  path: "^1.6.0"
-  flutter_svg: "^0.13.0"
+  http: ^0.12.0
+  path_provider: ^1.2.0
+  path: ^1.6.0
+  flutter_svg: ^0.14.0
 
 dev_dependencies:
   flutter_test:
     sdk: flutter
   test: "^1.6.0"
 
 environment:
-  sdk: ">=2.1.0 <3.0.0"
+  sdk: ">=2.3.0 <3.0.0"
   flutter: ">=1.6.0 <2.0.0"

test/download_test.dart

@@ -40,7 +40,7 @@ void main() {
             const Duration(milliseconds: 100),
             1.0,
             const Duration(seconds: 5),
-            (_, v) => print(v),
+            (_, v) => print(v.length),
             () => Future.value(realUrl),
             printError: true,
           ),
@@ -59,20 +59,20 @@ void main() {
             const Duration(milliseconds: 100),
             1.0,
             const Duration(seconds: 5),
-            (_, v) => print(v),
+            (_, v) => print(v.length),
             () => Future.value(realUrl),
             printError: true,
           ),
           result);
     });
-    test('=> bad url', () async {
+    test('=> bad url with skip 404 retry', () async {
       var url =
           'https://assets-cdn.github.com/images/modules/logos_page/GitHub-Mark.png';
 
       expect(
-          await loadFromRemote(url, null, 0, const Duration(milliseconds: 100),
+          await loadFromRemote(url, null, 5, const Duration(milliseconds: 100),
               1.0, const Duration(seconds: 5), null, null,
-              printError: true),
+              skipRetryStatusCode: [404], printError: true),
           null);
     });
     test('=> not a url', () async {