Merge pull request #11 from MelbourneDeveloper/asynclocking

Async Locking

Author: MelbourneDeveloper

.github/workflows/build_and_test.yml

@@ -20,7 +20,7 @@ jobs:
 
       - uses: subosito/flutter-action@v2
         with:
-          flutter-version: "3.7.5"
+          flutter-version: "3.10.6"
           channel: "stable"
           cache: true
           cache-key: "flutter-:os:-:channel:-:version:-:arch:-:hash:"
@@ -33,7 +33,7 @@ jobs:
         run: dart analyze lib --no-fatal-warnings
 
       - name: Check Formatting
-        run: flutter format lib --set-exit-if-changed
+        run: dart format lib --set-exit-if-changed
 
       - name: Run Tests
         run: flutter test --coverage --update-goldens

analysis_options.yaml

@@ -1,37 +1,3 @@
 include: package:austerity/analysis_options.yaml
 
-dart_code_metrics:
-  anti-patterns:
-    - long-method:
-        severity: error
-    - long-parameter-list:
-        severity: error
-  metrics:
-    cyclomatic-complexity: 20
-    maximum-nesting-level: 5
-    number-of-parameters: 4
-    source-lines-of-code: 50
-    weight-of-class: 0.33
-    halstead-volume: 150
-  metrics-exclude:
-  rules:
-    - newline-before-return:
-        severity: error
-    - no-boolean-literal-compare:
-        severity: error
-    - no-empty-block:
-        severity: error
-    - prefer-trailing-comma:
-        severity: error
-    - prefer-conditional-expressions:
-        severity: error
-    - no-equal-then-else:
-        severity: error
-    - avoid-restricted-imports:
-        severity: error
-    - avoid-global-state:
-        severity: error
-    - avoid-ignoring-return-values:
-        severity: warning
-    - avoid-late-keyword:
-        severity: error
+

benchmarks/pubspec.lock

@@ -153,6 +153,13 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.0.3"
+  ioc_container:
+    dependency: "direct main"
+    description:
+      path: ".."
+      relative: true
+    source: path
+    version: "1.0.12"
   js:
     dependency: transitive
     description:
@@ -418,4 +425,4 @@ packages:
     source: hosted
     version: "3.1.1"
 sdks:
-  dart: ">=2.18.2 <3.0.0"
+  dart: ">=2.18.2 <4.0.0"

example/pubspec.lock

@@ -5,10 +5,10 @@ packages:
     dependency: transitive
     description:
       name: async
-      sha256: bfe67ef28df125b7dddcea62755991f807aa39a2492a23e1550161692950bbe0
+      sha256: "947bfcf187f74dbc5e146c9eb9c0f10c9f8b30743e341481c1e2ed3ecc18c20c"
       url: "https://pub.dev"
     source: hosted
-    version: "2.10.0"
+    version: "2.11.0"
   austerity:
     dependency: "direct dev"
     description:
@@ -29,10 +29,10 @@ packages:
     dependency: transitive
     description:
       name: characters
-      sha256: e6a326c8af69605aec75ed6c187d06b349707a27fbff8222ca9cc2cff167975c
+      sha256: "04a925763edad70e8443c99234dc3328f442e811f1d8fd1a72f1c8ad0f69a605"
       url: "https://pub.dev"
     source: hosted
-    version: "1.2.1"
+    version: "1.3.0"
   clock:
     dependency: transitive
     description:
@@ -45,10 +45,10 @@ packages:
     dependency: transitive
     description:
       name: collection
-      sha256: cfc915e6923fe5ce6e153b0723c753045de46de1b4d63771530504004a45fae0
+      sha256: "4a07be6cb69c84d677a6c3096fcf960cc3285a8330b4603e0d463d15d9bd934c"
       url: "https://pub.dev"
     source: hosted
-    version: "1.17.0"
+    version: "1.17.1"
   cupertino_icons:
     dependency: "direct main"
     description:
@@ -89,15 +89,15 @@ packages:
       path: ".."
       relative: true
     source: path
-    version: "1.0.11"
+    version: "1.0.12"
   js:
     dependency: transitive
     description:
       name: js
-      sha256: "5528c2f391ededb7775ec1daa69e65a2d61276f7552de2b5f7b8d34ee9fd4ab7"
+      sha256: f2c445dce49627136094980615a031419f7f3eb393237e4ecd97ac15dea343f3
       url: "https://pub.dev"
     source: hosted
-    version: "0.6.5"
+    version: "0.6.7"
   lints:
     dependency: transitive
     description:
@@ -110,10 +110,10 @@ packages:
     dependency: transitive
     description:
       name: matcher
-      sha256: "16db949ceee371e9b99d22f88fa3a73c4e59fd0afed0bd25fc336eb76c198b72"
+      sha256: "6501fbd55da300384b768785b83e5ce66991266cec21af89ab9ae7f5ce1c4cbb"
       url: "https://pub.dev"
     source: hosted
-    version: "0.12.13"
+    version: "0.12.15"
   material_color_utilities:
     dependency: transitive
     description:
@@ -126,18 +126,18 @@ packages:
     dependency: transitive
     description:
       name: meta
-      sha256: "6c268b42ed578a53088d834796959e4a1814b5e9e164f147f580a386e5decf42"
+      sha256: "3c74dbf8763d36539f114c799d8a2d87343b5067e9d796ca22b5eb8437090ee3"
       url: "https://pub.dev"
     source: hosted
-    version: "1.8.0"
+    version: "1.9.1"
   path:
     dependency: transitive
     description:
       name: path
-      sha256: db9d4f58c908a4ba5953fcee2ae317c94889433e5024c27ce74a37f94267945b
+      sha256: "8829d8a55c13fc0e37127c29fedf290c102f4e40ae94ada574091fe0ff96c917"
       url: "https://pub.dev"
     source: hosted
-    version: "1.8.2"
+    version: "1.8.3"
   retry:
     dependency: "direct main"
     description:
@@ -195,10 +195,10 @@ packages:
     dependency: transitive
     description:
       name: test_api
-      sha256: ad540f65f92caa91bf21dfc8ffb8c589d6e4dc0c2267818b4cc2792857706206
+      sha256: eb6ac1540b26de412b3403a163d919ba86f6a973fe6cc50ae3541b80092fdcfb
       url: "https://pub.dev"
     source: hosted
-    version: "0.4.16"
+    version: "0.5.1"
   vector_math:
     dependency: transitive
     description:
@@ -208,4 +208,4 @@ packages:
     source: hosted
     version: "2.1.4"
 sdks:
-  dart: ">=2.18.2 <3.0.0"
+  dart: ">=3.0.0-0 <4.0.0"

lib/async_lock.dart

@@ -0,0 +1,59 @@
+import 'dart:async';
+
+/// A lock that ensures that only one async function executes at a time.
+class AsyncLock<T> {
+  /// Creates a new [AsyncLock].
+  AsyncLock(this.function, {this.retainFutureErrors = false});
+
+  /// The function to execute.
+  final Future<T> Function() function;
+
+  Completer<T>? _completer;
+
+  /// Whether to retain errors or allow reentrancy until the Future completes
+  /// successfully.
+  final bool retainFutureErrors;
+
+  /// Executes the given [function] and returns the value, but ensures that
+  /// only one async function executes at a time. The call defaults to a
+  /// timeout of 5 minutes.
+  Future<T> execute([Duration timeout = const Duration(minutes: 5)]) async {
+    try {
+      if (_completer != null) {
+        return _completer!.future;
+      } else {
+        _completer = Completer<T>();
+      }
+
+      final result = await function().timeout(
+        timeout,
+        onTimeout: () {
+          //On timeout complete with an error
+          final error = TimeoutException('Timeout of $timeout exceeded.');
+          _completer!.completeError(error);
+          if (!retainFutureErrors) {
+            //Clear the completer/error if we're not hanging on to it
+            //TODO: verify this happens in all cases
+            _completer = null;
+          }
+          throw error;
+        },
+      );
+
+      _completer!.complete(result);
+      return result;
+      // ignore: avoid_catches_without_on_clauses
+    } catch (error, stackTrace) {
+      // coverage:ignore-start
+      //This is only here for some potential future use cases
+      if (retainFutureErrors) {
+        _completer!.completeError(error, stackTrace);
+        // coverage:ignore-end
+      } else {
+        _completer = null;
+      }
+
+      rethrow;
+    }
+  }
+}