[gui] read everything from grpc response streams

we have bidirectional streaming rpcs, but we usually send only one
response back on that stream for most operations. therefore, the gui
would only read data from the stream until it got the first reply. but
this introduced errors in which the stream was disposed too early. now
we read everything from the stream, so that issue shouldn't happen.

src/client/gui/lib/grpc_client.dart

@@ -1,6 +1,6 @@
+import 'dart:async';
 import 'dart:io';
 
-import 'package:async/async.dart';
 import 'package:fpdart/fpdart.dart';
 import 'package:grpc/grpc.dart';
 import 'package:protobuf/protobuf.dart' hide RpcClient;
@@ -100,7 +100,7 @@ class GrpcClient {
         .start(Stream.value(request))
         .doOnData(checkForUpdate)
         .doOnEach(logGrpc(request))
-        .firstOrNull;
+        .lastOrNull;
   }
 
   Future<StopReply?> stop(Iterable<String> names) {
@@ -111,7 +111,7 @@ class GrpcClient {
     return _client
         .stop(Stream.value(request))
         .doOnEach(logGrpc(request))
-        .firstOrNull;
+        .lastOrNull;
   }
 
   Future<SuspendReply?> suspend(Iterable<String> names) {
@@ -122,7 +122,7 @@ class GrpcClient {
     return _client
         .suspend(Stream.value(request))
         .doOnEach(logGrpc(request))
-        .firstOrNull;
+        .lastOrNull;
   }
 
   Future<RestartReply?> restart(Iterable<String> names) {
@@ -134,7 +134,7 @@ class GrpcClient {
         .restart(Stream.value(request))
         .doOnData(checkForUpdate)
         .doOnEach(logGrpc(request))
-        .firstOrNull;
+        .lastOrNull;
   }
 
   Future<DeleteReply?> delete(Iterable<String> names) {
@@ -147,7 +147,7 @@ class GrpcClient {
     return _client
         .delet(Stream.value(request))
         .doOnEach(logGrpc(request))
-        .firstOrNull;
+        .lastOrNull;
   }
 
   Future<RecoverReply?> recover(Iterable<String> names) {
@@ -158,7 +158,7 @@ class GrpcClient {
     return _client
         .recover(Stream.value(request))
         .doOnEach(logGrpc(request))
-        .firstOrNull;
+        .lastOrNull;
   }
 
   Future<DeleteReply?> purge(Iterable<String> names) {
@@ -172,7 +172,7 @@ class GrpcClient {
     return _client
         .delet(Stream.value(request))
         .doOnEach(logGrpc(request))
-        .firstOrNull;
+        .lastOrNull;
   }
 
   Future<List<VmInfo>> info([Iterable<String> names = const []]) {
@@ -193,7 +193,7 @@ class GrpcClient {
     return _client
         .mount(Stream.value(request))
         .doOnEach(logGrpc(request))
-        .firstOrNull;
+        .lastOrNull;
   }
 
   Future<void> umount(String name, [String? path]) {
@@ -204,7 +204,7 @@ class GrpcClient {
     return _client
         .umount(Stream.value(request))
         .doOnEach(logGrpc(request))
-        .firstOrNull;
+        .lastOrNull;
   }
 
   Future<FindReply> find({bool images = true, bool blueprints = true}) {
@@ -254,7 +254,7 @@ class GrpcClient {
     return _client
         .set(Stream.value(request))
         .doOnEach(logGrpc(request))
-        .firstOrNull;
+        .lastOrNull;
   }
 
   Future<SSHInfo?> sshInfo(String name) {
@@ -263,7 +263,7 @@ class GrpcClient {
     return _client
         .ssh_info(Stream.value(request))
         .doOnEach(logGrpc(request))
-        .first
+        .last
         .then((reply) => reply.sshInfo[name]);
   }
 
@@ -299,3 +299,17 @@ class CustomChannelCredentials extends ChannelCredentials {
     return ctx;
   }
 }
+
+extension<T> on Stream<T> {
+  Future<T?> get lastOrNull {
+    final completer = Completer<T?>.sync();
+    T? result;
+    listen(
+      (event) => result = event,
+      onError: completer.completeError,
+      onDone: () => completer.complete(result),
+      cancelOnError: true,
+    );
+    return completer.future;
+  }
+}

src/client/gui/lib/providers.dart

@@ -68,9 +68,6 @@ final daemonAvailableProvider = Provider((ref) {
     if (message.contains('failed to obtain exit status for remote process')) {
       return true;
     }
-    if (message.contains('Connection is being forcefully terminated')) {
-      return true;
-    }
   }
   return false;
 });