feat(graphql_flutter): work on making subscriptions more of a first-c…

…lass citizen
zino-hofmann · May 23, 2020 · a0e0d5c · a0e0d5c
1 parent 6d0b045
commit a0e0d5c
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Showing 4 changed files with 45 additions and 220 deletions.
diff --git a/packages/graphql_flutter/lib/src/widgets/_subscription.dart b/packages/graphql_flutter/lib/src/widgets/_subscription.dart
diff --git a/packages/graphql_flutter/lib/src/widgets/mutation.dart b/packages/graphql_flutter/lib/src/widgets/mutation.dart
@@ -1,7 +1,6 @@
 import 'package:flutter/widgets.dart';
 
 import 'package:graphql/client.dart';
-import 'package:graphql/internal.dart';
 
 import 'package:graphql_flutter/src/widgets/graphql_provider.dart';
 
@@ -54,7 +53,7 @@ class MutationState extends State<Mutation> {
   bool _setNewOptions() {
     final _cached = __cachedOptions;
     final _new = _providedOptions;
-    if (_cached == null || !_new.areEqualTo(_cached)) {
+    if (_cached == null || !_new.equal(_cached)) {
       __cachedOptions = _new;
       return true;
     }
@@ -94,7 +93,7 @@ class MutationState extends State<Mutation> {
     Map<String, dynamic> variables, {
     Object optimisticResult,
   }) {
-    final mutationCallbacks = MutationCallbacks(
+    final mutationCallbacks = MutationCallbackHandler(
       cache: client.cache,
       queryId: observableQuery.queryId,
       options: widget.options,
@@ -118,11 +117,7 @@ class MutationState extends State<Mutation> {
   @override
   Widget build(BuildContext context) {
     return StreamBuilder<QueryResult>(
-      // we give the stream builder a key so that
-      // toggling mutations at the same place in the tree,
-      // such as is done in the example, won't result in bugs
-      key: Key(observableQuery?.options?.toKey()),
-      initialData: observableQuery?.latestResult ?? QueryResult(),
+      initialData: observableQuery?.latestResult ?? QueryResult(source: null),
       stream: observableQuery?.stream,
       builder: (
         BuildContext buildContext,

diff --git a/packages/graphql_flutter/lib/src/widgets/query.dart b/packages/graphql_flutter/lib/src/widgets/query.dart
@@ -1,7 +1,6 @@
 import 'package:flutter/widgets.dart';
 
 import 'package:graphql/client.dart';
-import 'package:graphql/internal.dart';
 
 import 'package:graphql_flutter/src/widgets/graphql_provider.dart';
 
@@ -35,20 +34,8 @@ class Query extends StatefulWidget {
 class QueryState extends State<Query> {
   ObservableQuery observableQuery;
   GraphQLClient _client;
-  WatchQueryOptions get _options {
-    final QueryOptions options = widget.options;
-
-    return WatchQueryOptions(
-      document: options.document,
-      variables: options.variables,
-      fetchPolicy: options.fetchPolicy,
-      errorPolicy: options.errorPolicy,
-      pollInterval: options.pollInterval,
-      fetchResults: true,
-      context: options.context,
-      optimisticResult: options.optimisticResult,
-    );
-  }
+
+  WatchQueryOptions get _options => widget.options.asWatchQueryOptions();
 
   void _initQuery() {
     observableQuery?.close();
@@ -76,7 +63,7 @@ class QueryState extends State<Query> {
     optionsWithOverrides.policies = client.defaultPolicies.watchQuery
         .withOverrides(optionsWithOverrides.policies);
 
-    if (!observableQuery.options.areEqualTo(optionsWithOverrides)) {
+    if (!observableQuery.options.equal(optionsWithOverrides)) {
       _initQuery();
     }
   }
@@ -90,7 +77,6 @@ class QueryState extends State<Query> {
   @override
   Widget build(BuildContext context) {
     return StreamBuilder<QueryResult>(
-      key: Key(observableQuery?.options?.toKey()),
       initialData: observableQuery?.latestResult ?? QueryResult.loading(),
       stream: observableQuery.stream,
       builder: (

diff --git a/packages/graphql_flutter/lib/src/widgets/subscription.dart b/packages/graphql_flutter/lib/src/widgets/subscription.dart
@@ -3,99 +3,69 @@ import 'dart:io';
 
 import 'package:connectivity/connectivity.dart';
 import 'package:flutter/widgets.dart';
-import 'package:gql/language.dart';
-import 'package:gql_exec/gql_exec.dart';
 import 'package:graphql/client.dart';
-import 'package:graphql/internal.dart';
+import 'package:graphql_flutter/graphql_flutter.dart';
 import 'package:graphql_flutter/src/widgets/graphql_provider.dart';
 
-typedef OnSubscriptionCompleted = void Function();
+typedef OnSubscriptionResult = void Function(
+  QueryResult subscriptionResult,
+  GraphQLClient client,
+);
 
-typedef SubscriptionBuilder<T> = Widget Function({
-  bool loading,
-  T payload,
-  dynamic error,
-});
+typedef SubscriptionBuilder = Widget Function(QueryResult result);
 
 class Subscription<T> extends StatefulWidget {
-  const Subscription(
-    this.operationName,
-    this.query, {
-    this.variables = const <String, dynamic>{},
-    final Key key,
+  const Subscription({
+    @required this.options,
     @required this.builder,
-    this.initial,
-    this.onCompleted,
+    this.onSubscriptionResult,
+    Key key,
   }) : super(key: key);
 
-  final String operationName;
-  final String query;
-  final Map<String, dynamic> variables;
-  final SubscriptionBuilder<T> builder;
-  final OnSubscriptionCompleted onCompleted;
-  final T initial;
+  final SubscriptionOptions options;
+  final SubscriptionBuilder builder;
+  final OnSubscriptionResult onSubscriptionResult;
 
   @override
   _SubscriptionState<T> createState() => _SubscriptionState<T>();
 }
 
 class _SubscriptionState<T> extends State<Subscription<T>> {
-  bool _loading = true;
-  T _data;
-  dynamic _error;
-  StreamSubscription<Response> _subscription;
-  GraphQLClient _client;
+  Stream<QueryResult> stream;
+  GraphQLClient client;
 
   ConnectivityResult _currentConnectivityResult;
   StreamSubscription<ConnectivityResult> _networkSubscription;
 
   void _initSubscription() {
     final GraphQLClient client = GraphQLProvider.of(context).value;
     assert(client != null);
-    final Request request = Request(
-      operation: Operation(
-        document: parseString(widget.query),
-        operationName: widget.operationName,
-      ),
-      variables: widget.variables,
-    );
 
-    final Stream<Response> stream = _client.subscribe(request);
+    stream = client.subscribe(widget.options);
 
-    if (_subscription == null) {
-      // Set the initial value for the first time.
-      if (widget.initial != null) {
-        setState(() {
-          _loading = true;
-          _data = widget.initial;
-          _error = null;
-        });
-      }
+    if (widget.onSubscriptionResult != null) {
+      stream = stream.map((result) {
+        widget.onSubscriptionResult(result, client);
+        return result;
+      });
     }
-
-    _subscription?.cancel();
-    _subscription = stream.listen(
-      _onData,
-      onError: _onError,
-      onDone: _onDone,
-    );
   }
 
   @override
   void initState() {
-    _networkSubscription = Connectivity().onConnectivityChanged.listen(
-        (ConnectivityResult result) async => await _onNetworkChange(result));
+    _networkSubscription =
+        Connectivity().onConnectivityChanged.listen(_onNetworkChange);
 
     super.initState();
   }
 
   @override
   void didChangeDependencies() {
     super.didChangeDependencies();
-    final GraphQLClient client = GraphQLProvider.of(context).value;
-    assert(client != null);
-    if (client != _client) {
-      _client = client;
+    final GraphQLClient newClient = GraphQLProvider.of(context).value;
+    assert(newClient != null);
+    if (client != newClient) {
+      client = newClient;
       _initSubscription();
     }
   }
@@ -104,42 +74,17 @@ class _SubscriptionState<T> extends State<Subscription<T>> {
   void didUpdateWidget(Subscription<T> oldWidget) {
     super.didUpdateWidget(oldWidget);
 
-    if (widget.query != oldWidget.query ||
-        widget.operationName != oldWidget.operationName ||
-        areDifferentVariables(widget.variables, oldWidget.variables)) {
+    if (!widget.options.equal(oldWidget.options)) {
       _initSubscription();
     }
   }
 
   @override
   void dispose() {
-    _subscription?.cancel();
     _networkSubscription?.cancel();
     super.dispose();
   }
 
-  void _onData(final Response message) {
-    setState(() {
-      _loading = false;
-      _data = message.data as T;
-      _error = message.errors;
-    });
-  }
-
-  void _onError(final Object error) {
-    setState(() {
-      _loading = false;
-      _data = null;
-      _error = error;
-    });
-  }
-
-  void _onDone() {
-    if (widget.onCompleted != null) {
-      widget.onCompleted();
-    }
-  }
-
   Future _onNetworkChange(ConnectivityResult result) async {
     //if from offline to online
     if (_currentConnectivityResult == ConnectivityResult.none &&
@@ -170,10 +115,17 @@ class _SubscriptionState<T> extends State<Subscription<T>> {
 
   @override
   Widget build(final BuildContext context) {
-    return widget.builder(
-      loading: _loading,
-      error: _error,
-      payload: _data,
+    return StreamBuilder<QueryResult>(
+      initialData: widget.options?.optimisticResult != null
+          ? QueryResult.optimistic(data: widget.options?.optimisticResult)
+          : QueryResult.loading(),
+      stream: stream,
+      builder: (
+        BuildContext buildContext,
+        AsyncSnapshot<QueryResult> snapshot,
+      ) {
+        return widget?.builder(snapshot.data);
+      },
     );
   }
 }