add FlatMapPolicy & release 1.2.1 - Jun 17, 2021 (#5)

* add

* docs

* change dispose to a func

* dart format

* docs and bump version

* docs and bump version

* LICENSE

Author: hoc081098

CHANGELOG.md

@@ -1,3 +1,15 @@
+## 1.2.1 - Jun 17, 2021
+
+*   Change `dispose` from a field to a function.
+*   Add `FlatMapPolicy` allow changing _flatMap behavior_ of `loaderFunction` and `refresherFunction`.
+    ```dart
+    LoaderBloc(
+      ...,
+      loaderFlatMapPolicy: FlatMapPolicy.concat, // asyncExpand
+      refreshFlatMapPolicy: FlatMapPolicy.latest, // switchMap
+    );
+    ```
+
 ## 1.2.0 - May 10, 2021
 
 *   Update `rxdart` to `0.27.0`.

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2020 Petrus Nguyễn Thái Học
+Copyright (c) 2020-2021 Petrus Nguyễn Thái Học
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -29,7 +29,7 @@ dependencies:
     <img src="https://github.com/hoc081098/hoc081098.github.io/raw/master/stream_loader/untitled.gif" height="480"/>
 </p>
 
-#### Model and api
+#### 1. Model and api
 ```dart
 abstract class Comment implements Built<Comment, CommentBuilder> { ... }
 
@@ -40,7 +40,7 @@ class Api {
 final api = Api();
 ```
 
-#### Create LoaderWidget load comments from api
+#### 2. Create LoaderWidget load comments from api
 ```dart
 import 'package:stream_loader/stream_loader.dart';
 
@@ -74,7 +74,7 @@ LoaderWidget<BuiltList<Comment>>(
 );
 ```
 
-#### Create LoaderWidget load comment detail from api
+#### 3. Create LoaderWidget load comment detail from api
 ```dart
 import 'package:stream_loader/stream_loader.dart';
 
@@ -153,7 +153,21 @@ class _CommentsState extends State<Comments> {
 }
 ```
 
+### Change _flatMap behavior_ of `loaderFunction` and `refresherFunction`.
+
+-   Default behavior of `loaderFunction` is `FlatMapPolicy.latest` (uses `switchMap`).
+-   Default behavior of `refreshFlatMapPolicy` is `FlatMapPolicy.first`, (uses `exhaustMap`).
+-   To change them, passing your value to `LoaderBloc` constructor
+
+```dart
+LoaderBloc(
+  ...,
+  loaderFlatMapPolicy: FlatMapPolicy.concat, // asyncExpand
+  refreshFlatMapPolicy: FlatMapPolicy.latest, // switchMap
+);
+```
+
 ## License
     MIT License
 
-    Copyright (c) 2020 Petrus Nguyễn Thái Học
+    Copyright (c) 2020-2021 Petrus Nguyễn Thái Học

example/pubspec.lock

@@ -28,7 +28,7 @@ packages:
       name: async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.5.0"
+    version: "2.6.1"
   boolean_selector:
     dependency: transitive
     description:
@@ -421,7 +421,7 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0"
+    version: "1.8.1"
   stack_trace:
     dependency: transitive
     description:
@@ -442,7 +442,7 @@ packages:
       path: ".."
       relative: true
     source: path
-    version: "1.2.0"
+    version: "1.2.1"
   stream_transform:
     dependency: transitive
     description:
@@ -470,7 +470,7 @@ packages:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.19"
+    version: "0.3.0"
   timing:
     dependency: transitive
     description:

lib/src/loader_bloc.dart

@@ -4,16 +4,7 @@ import 'package:disposebag/disposebag.dart' show DisposeBag;
 import 'package:distinct_value_connectable_stream/distinct_value_connectable_stream.dart'
     show DistinctValueConnectableExtensions, DistinctValueStream;
 import 'package:meta/meta.dart' show visibleForTesting;
-import 'package:rxdart_ext/rxdart_ext.dart'
-    show
-        PublishSubject,
-        Rx,
-        SwitchMapExtension,
-        ExhaustMapExtension,
-        DoExtensions,
-        OnErrorExtensions,
-        ScanExtension,
-        StartWithExtension;
+import 'package:rxdart_ext/rxdart_ext.dart';
 
 import 'loader_message.dart';
 import 'loader_state.dart';
@@ -22,6 +13,37 @@ import 'utils.dart';
 
 // ignore_for_file: close_sinks
 
+/// Defines which flatMap behavior should be applied whenever a new values is emitted.
+enum FlatMapPolicy {
+  /// uses [FlatMapExtension.flatMap].
+  merge,
+
+  /// uses [Stream.asyncExpand].
+  concat,
+
+  /// uses [SwitchMapExtension.switchMap].
+  latest,
+
+  /// uses [ExhaustMapExtension.exhaustMap].
+  first,
+}
+
+extension _FlatMapWithPolicy<T> on Stream<T> {
+  Stream<R> flatMapWithPolicy<R>(
+      FlatMapPolicy policy, Stream<R> Function(T) transform) {
+    switch (policy) {
+      case FlatMapPolicy.merge:
+        return flatMap(transform);
+      case FlatMapPolicy.concat:
+        return asyncExpand(transform);
+      case FlatMapPolicy.latest:
+        return switchMap(transform);
+      case FlatMapPolicy.first:
+        return exhaustMap(transform);
+    }
+  }
+}
+
 /// BLoC that handles loading and refreshing data
 class LoaderBloc<Content extends Object> {
   static const _tag = '« stream_loader »';
@@ -32,22 +54,23 @@ class LoaderBloc<Content extends Object> {
   /// Message stream
   final Stream<LoaderMessage<Content>> message$;
 
-  /// Call this function fetch data
+  /// Call this function to fetch data
   final void Function() fetch;
 
   /// Call this function to refresh data
   final Future<void> Function() refresh;
 
   /// Clean up resources
-  final Future<void> Function() dispose;
+  Future<void> dispose() => _dispose();
+  final Future<void> Function() _dispose;
 
   LoaderBloc._({
-    required this.dispose,
+    required Future<void> Function() dispose,
     required this.state$,
     required this.fetch,
     required this.refresh,
     required this.message$,
-  });
+  }) : _dispose = dispose;
 
   /// Construct a [LoaderBloc]
   /// The [loaderFunction] is a function return a stream of [Content]s (must be not null).
@@ -63,6 +86,10 @@ class LoaderBloc<Content extends Object> {
     Stream<Content> Function()? refresherFunction,
     Content? initialContent,
     void Function(String)? logger,
+    FlatMapPolicy loaderFlatMapPolicy =
+        FlatMapPolicy.latest, // default is `switchMap`
+    FlatMapPolicy refreshFlatMapPolicy =
+        FlatMapPolicy.first, // default is `exhaustMap`
   }) {
     refresherFunction ??= () => Stream<Content>.empty();
 
@@ -73,7 +100,8 @@ class LoaderBloc<Content extends Object> {
     final controllers = <StreamController<dynamic>>[fetchS, refreshS, messageS];
 
     /// Input actions to state
-    final fetchChanges = fetchS.stream.switchMap(
+    final fetchChanges = fetchS.stream.flatMapWithPolicy(
+      loaderFlatMapPolicy,
       (_) => Rx.defer(loaderFunction)
           .doOnData(
               (content) => messageS.add(LoaderMessage.fetchSuccess(content)))
@@ -84,7 +112,8 @@ class LoaderBloc<Content extends Object> {
           .onErrorReturnWith(
               (e, _) => LoaderPartialStateChange.fetchFailure(e)),
     );
-    final refreshChanges = refreshS.stream.exhaustMap(
+    final refreshChanges = refreshS.stream.flatMapWithPolicy(
+      refreshFlatMapPolicy,
       (completer) => Rx.defer(refresherFunction!)
           .doOnData(
               (content) => messageS.add(LoaderMessage.refreshSuccess(content)))

pubspec.lock

@@ -28,7 +28,7 @@ packages:
       name: async
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "2.5.0"
+    version: "2.6.1"
   boolean_selector:
     dependency: transitive
     description:
@@ -386,7 +386,7 @@ packages:
       name: source_span
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "1.8.0"
+    version: "1.8.1"
   stack_trace:
     dependency: transitive
     description:
@@ -428,7 +428,7 @@ packages:
       name: test_api
       url: "https://pub.dartlang.org"
     source: hosted
-    version: "0.2.19"
+    version: "0.3.0"
   timing:
     dependency: transitive
     description:

pubspec.yaml

@@ -1,6 +1,6 @@
 name: stream_loader
 description: A flutter plugin for loading content asynchronously with Dart stream. RxDart loader bloc.
-version: 1.2.0
+version: 1.2.1
 homepage: https://github.com/hoc081098/stream_loader.git
 repository: https://github.com/hoc081098/stream_loader.git
 issue_tracker: https://github.com/hoc081098/stream_loader/issues