Add an onRetry() callback
diff --git a/lib/http_retry.dart b/lib/http_retry.dart
index b50d680..4f30e03 100644
--- a/lib/http_retry.dart
+++ b/lib/http_retry.dart
@@ -22,6 +22,9 @@
/// The callback that determines how long to wait before retrying a request.
final Duration Function(int) _delay;
+ /// The callback to call to indicate that a request is being retried.
+ final void Function(BaseRequest, BaseResponse, int) _onRetry;
+
/// Creates a client wrapping [inner] that retries HTTP requests.
///
/// This retries a failing request [retries] times (3 by default). Note that
@@ -35,15 +38,20 @@
/// retry, then increases the delay by 1.5x for each subsequent retry. If
/// [delay] is passed, it's used to determine the time to wait before the
/// given (zero-based) retry.
+ ///
+ /// If [onRetry] is passed, it's called immediately before each retry so that
+ /// the client has a chance to perform side effects like logging.
RetryClient(this._inner,
{int retries,
bool when(BaseResponse response),
- Duration delay(int retryCount)})
+ Duration delay(int retryCount),
+ void onRetry(BaseRequest request, BaseResponse response, int retryCount)})
: _retries = retries ?? 3,
_when = when ?? ((response) => response.statusCode == 503),
_delay = delay ??
((retryCount) =>
- new Duration(milliseconds: 500) * math.pow(1.5, retryCount)) {
+ new Duration(milliseconds: 500) * math.pow(1.5, retryCount)),
+ _onRetry = onRetry {
RangeError.checkNotNegative(_retries, "retries");
}
@@ -54,15 +62,18 @@
/// in order. It will wait for `delays[0]` after the initial request,
/// `delays[1]` after the first retry, and so on.
RetryClient.withDelays(Client inner, Iterable<Duration> delays,
- {bool when(BaseResponse response)})
- : this._withDelays(inner, delays.toList(), when: when);
+ {bool when(BaseResponse response),
+ void onRetry(BaseRequest request, BaseResponse response, int retryCount)})
+ : this._withDelays(inner, delays.toList(), when: when, onRetry: onRetry);
RetryClient._withDelays(Client inner, List<Duration> delays,
- {bool when(BaseResponse response)})
+ {bool when(BaseResponse response),
+ void onRetry(BaseRequest request, BaseResponse response, int retryCount)})
: this(inner,
retries: delays.length,
delay: (retryCount) => delays[retryCount],
- when: when);
+ when: when,
+ onRetry: onRetry);
Future<StreamedResponse> send(BaseRequest request) async {
var splitter = new StreamSplitter(request.finalize());
@@ -76,6 +87,7 @@
// dangling connections.
response.stream.listen((_) {}).cancel()?.catchError((_) {});
await new Future.delayed(_delay(i));
+ if (_onRetry != null) _onRetry(request, response, i);
i++;
}
}
diff --git a/pubspec.yaml b/pubspec.yaml
index 6af9806..b2b3c7e 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
name: http_retry
-version: 0.1.0-dev
+version: 0.1.0
description: HTTP client middleware that automatically retries requests.
author: Dart Team <misc@dartlang.org>
homepage: https://github.com/dart-lang/http_retry
diff --git a/test/http_retry_test.dart b/test/http_retry_test.dart
index 3ba61b4..a0f4d30 100644
--- a/test/http_retry_test.dart
+++ b/test/http_retry_test.dart
@@ -162,6 +162,23 @@
});
});
+ test("calls onRetry for each retry", () async {
+ var count = 0;
+ var client = new RetryClient(
+ new MockClient(
+ expectAsync1((_) async => new Response("", 503), count: 3)),
+ retries: 2,
+ delay: (_) => Duration.ZERO,
+ onRetry: expectAsync3((request, response, retryCount) {
+ expect(request.url, equals(Uri.parse("http://example.org")));
+ expect(response.statusCode, equals(503));
+ expect(retryCount, equals(count));
+ count++;
+ }, count: 2));
+ var response = await client.get("http://example.org");
+ expect(response.statusCode, equals(503));
+ });
+
test("copies all request attributes for each attempt", () async {
var client = new RetryClient.withDelays(
new MockClient(expectAsync1((request) async {
