Offer subscribe/unsubscribe in channel action sheet

assets/l10n/app_en.arb

@@ -96,6 +96,14 @@
   "@permissionsDeniedReadExternalStorage": {
     "description": "Message for dialog asking the user to grant permissions for external storage read access."
   },
+  "actionSheetOptionSubscribe": "Subscribe",
+  "@actionSheetOptionSubscribe": {
+    "description": "Label in the channel action sheet for subscribing to the channel."
+  },
+  "subscribeFailedTitle": "Failed to subscribe",
+  "@subscribeFailedTitle": {
+    "description": "Error title when subscribing to a channel failed."
+  },
   "actionSheetOptionMarkChannelAsRead": "Mark channel as read",
   "@actionSheetOptionMarkChannelAsRead": {
     "description": "Label for marking a channel as read."
@@ -108,6 +116,29 @@
   "@actionSheetOptionListOfTopics": {
     "description": "Label for navigating to a channel's topic-list page."
   },
+  "actionSheetOptionUnsubscribe": "Unsubscribe",
+  "@actionSheetOptionUnsubscribe": {
+    "description": "Label in the channel action sheet for unsubscribing from the channel."
+  },
+  "unsubscribeConfirmationDialogTitle": "Unsubscribe from {channelName}?",
+  "@unsubscribeConfirmationDialogTitle": {
+    "description": "Title for a confirmation dialog for unsubscribing from a channel.",
+    "placeholders": {
+      "channelName": {"type": "String", "example": "mobile"}
+    }
+  },
+  "unsubscribeConfirmationDialogMessageMaybeCannotResubscribe": "Once you leave this channel, you might not be able to rejoin.",
+  "@unsubscribeConfirmationDialogMessageMaybeCannotResubscribe": {
+    "description": "Message for a confirmation dialog for unsubscribing from a channel when you might not have permission to resubscribe."
+  },
+  "unsubscribeConfirmationDialogConfirmButton": "Unsubscribe",
+  "@unsubscribeConfirmationDialogConfirmButton": {
+    "description": "Label for the 'Unsubscribe' button on a confirmation dialog for unsubscribing from a channel."
+  },
+  "unsubscribeFailedTitle": "Failed to unsubscribe",
+  "@unsubscribeFailedTitle": {
+    "description": "Error title when unsubscribing from a channel failed."
+  },
   "actionSheetOptionMuteTopic": "Mute topic",
   "@actionSheetOptionMuteTopic":  {
     "description": "Label for muting a topic on action sheet."

lib/api/route/channels.dart

@@ -4,6 +4,42 @@ import '../core.dart';
 import '../model/model.dart';
 part 'channels.g.dart';
 
+/// https://zulip.com/api/subscribe
+///
+/// [subscriptions] is a list of channel names.
+/// (This is one of the few remaining areas where the Zulip API hasn't migrated
+/// to using IDs.)
+Future<void> subscribeToChannel(ApiConnection connection, {
+  // TODO(server-future): This should use a stream ID, not stream name.
+  //   (Keep dartdoc up to date.)
+  //   Server issue: https://github.com/zulip/zulip/issues/10744
+  required List<String> subscriptions,
+  List<int>? principals,
+}) {
+  return connection.post('subscribeToChannel', (_) {}, 'users/me/subscriptions', {
+    'subscriptions': subscriptions.map((name) => {'name': name}).toList(),
+    if (principals != null) 'principals': principals,
+  });
+}
+
+/// https://zulip.com/api/unsubscribe
+///
+/// [subscriptions] is a list of channel names.
+/// (This is one of the few remaining areas where the Zulip API hasn't migrated
+/// to using IDs.)
+Future<void> unsubscribeFromChannel(ApiConnection connection, {
+  // TODO(server-future): This should use a stream ID, not stream name.
+  //   (Keep dartdoc up to date.)
+  //   Server issue: https://github.com/zulip/zulip/issues/10744
+  required List<String> subscriptions,
+  List<int>? principals,
+}) {
+  return connection.delete('unsubscribeFromChannel', (_) {}, 'users/me/subscriptions', {
+    'subscriptions': subscriptions,
+    if (principals != null) 'principals': principals,
+  });
+}
+
 /// https://zulip.com/api/get-stream-topics
 Future<GetStreamTopicsResult> getStreamTopics(ApiConnection connection, {
   required int streamId,

lib/generated/l10n/zulip_localizations.dart

@@ -275,6 +275,18 @@ abstract class ZulipLocalizations {
   /// **'To upload files, please grant Zulip additional permissions in Settings.'**
   String get permissionsDeniedReadExternalStorage;
 
+  /// Label in the channel context menu for subscribing to the channel.
+  ///
+  /// In en, this message translates to:
+  /// **'Subscribe'**
+  String get actionSheetOptionSubscribe;
+
+  /// Error title when subscribing to a channel failed.
+  ///
+  /// In en, this message translates to:
+  /// **'Failed to subscribe'**
+  String get subscribeFailedTitle;
+
   /// Label for marking a channel as read.
   ///
   /// In en, this message translates to:
@@ -293,6 +305,36 @@ abstract class ZulipLocalizations {
   /// **'List of topics'**
   String get actionSheetOptionListOfTopics;
 
+  /// Label in the channel context menu for unsubscribing from the channel.
+  ///
+  /// In en, this message translates to:
+  /// **'Unsubscribe'**
+  String get actionSheetOptionUnsubscribe;
+
+  /// Title for a confirmation dialog for unsubscribing from a channel.
+  ///
+  /// In en, this message translates to:
+  /// **'Unsubscribe from {channelName}?'**
+  String unsubscribeConfirmationDialogTitle(String channelName);
+
+  /// Message for a confirmation dialog for unsubscribing from a channel when you might not have permission to resubscribe.
+  ///
+  /// In en, this message translates to:
+  /// **'Once you leave this channel, you might not be able to rejoin.'**
+  String get unsubscribeConfirmationDialogMessageMaybeCannotResubscribe;
+
+  /// Label for the 'Unsubscribe' button on a confirmation dialog for unsubscribing from a channel.
+  ///
+  /// In en, this message translates to:
+  /// **'Unsubscribe'**
+  String get unsubscribeConfirmationDialogConfirmButton;
+
+  /// Error title when unsubscribing from a channel failed.
+  ///
+  /// In en, this message translates to:
+  /// **'Failed to unsubscribe'**
+  String get unsubscribeFailedTitle;
+
   /// Label for muting a topic on action sheet.
   ///
   /// In en, this message translates to:

lib/generated/l10n/zulip_localizations_ar.dart

@@ -87,6 +87,12 @@ class ZulipLocalizationsAr extends ZulipLocalizations {
   String get permissionsDeniedReadExternalStorage =>
       'To upload files, please grant Zulip additional permissions in Settings.';
 
+  @override
+  String get actionSheetOptionSubscribe => 'Subscribe';
+
+  @override
+  String get subscribeFailedTitle => 'Failed to subscribe';
+
   @override
   String get actionSheetOptionMarkChannelAsRead => 'Mark channel as read';
 
@@ -96,6 +102,24 @@ class ZulipLocalizationsAr extends ZulipLocalizations {
   @override
   String get actionSheetOptionListOfTopics => 'List of topics';
 
+  @override
+  String get actionSheetOptionUnsubscribe => 'Unsubscribe';
+
+  @override
+  String unsubscribeConfirmationDialogTitle(String channelName) {
+    return 'Unsubscribe from $channelName?';
+  }
+
+  @override
+  String get unsubscribeConfirmationDialogMessageMaybeCannotResubscribe =>
+      'Once you leave this channel, you might not be able to rejoin.';
+
+  @override
+  String get unsubscribeConfirmationDialogConfirmButton => 'Unsubscribe';
+
+  @override
+  String get unsubscribeFailedTitle => 'Failed to unsubscribe';
+
   @override
   String get actionSheetOptionMuteTopic => 'Mute topic';
 

lib/generated/l10n/zulip_localizations_de.dart

@@ -88,6 +88,12 @@ class ZulipLocalizationsDe extends ZulipLocalizations {
   String get permissionsDeniedReadExternalStorage =>
       'Bitte gewähre Zulip zusätzliche Berechtigungen in den Einstellungen, um Dateien hochzuladen.';
 
+  @override
+  String get actionSheetOptionSubscribe => 'Subscribe';
+
+  @override
+  String get subscribeFailedTitle => 'Failed to subscribe';
+
   @override
   String get actionSheetOptionMarkChannelAsRead =>
       'Kanal als gelesen markieren';
@@ -98,6 +104,24 @@ class ZulipLocalizationsDe extends ZulipLocalizations {
   @override
   String get actionSheetOptionListOfTopics => 'Themenliste';
 
+  @override
+  String get actionSheetOptionUnsubscribe => 'Unsubscribe';
+
+  @override
+  String unsubscribeConfirmationDialogTitle(String channelName) {
+    return 'Unsubscribe from $channelName?';
+  }
+
+  @override
+  String get unsubscribeConfirmationDialogMessageMaybeCannotResubscribe =>
+      'Once you leave this channel, you might not be able to rejoin.';
+
+  @override
+  String get unsubscribeConfirmationDialogConfirmButton => 'Unsubscribe';
+
+  @override
+  String get unsubscribeFailedTitle => 'Failed to unsubscribe';
+
   @override
   String get actionSheetOptionMuteTopic => 'Thema stummschalten';
 

lib/generated/l10n/zulip_localizations_en.dart

@@ -87,6 +87,12 @@ class ZulipLocalizationsEn extends ZulipLocalizations {
   String get permissionsDeniedReadExternalStorage =>
       'To upload files, please grant Zulip additional permissions in Settings.';
 
+  @override
+  String get actionSheetOptionSubscribe => 'Subscribe';
+
+  @override
+  String get subscribeFailedTitle => 'Failed to subscribe';
+
   @override
   String get actionSheetOptionMarkChannelAsRead => 'Mark channel as read';
 
@@ -96,6 +102,24 @@ class ZulipLocalizationsEn extends ZulipLocalizations {
   @override
   String get actionSheetOptionListOfTopics => 'List of topics';
 
+  @override
+  String get actionSheetOptionUnsubscribe => 'Unsubscribe';
+
+  @override
+  String unsubscribeConfirmationDialogTitle(String channelName) {
+    return 'Unsubscribe from $channelName?';
+  }
+
+  @override
+  String get unsubscribeConfirmationDialogMessageMaybeCannotResubscribe =>
+      'Once you leave this channel, you might not be able to rejoin.';
+
+  @override
+  String get unsubscribeConfirmationDialogConfirmButton => 'Unsubscribe';
+
+  @override
+  String get unsubscribeFailedTitle => 'Failed to unsubscribe';
+
   @override
   String get actionSheetOptionMuteTopic => 'Mute topic';
 

lib/generated/l10n/zulip_localizations_fr.dart

@@ -87,6 +87,12 @@ class ZulipLocalizationsFr extends ZulipLocalizations {
   String get permissionsDeniedReadExternalStorage =>
       'To upload files, please grant Zulip additional permissions in Settings.';
 
+  @override
+  String get actionSheetOptionSubscribe => 'Subscribe';
+
+  @override
+  String get subscribeFailedTitle => 'Failed to subscribe';
+
   @override
   String get actionSheetOptionMarkChannelAsRead => 'Mark channel as read';
 
@@ -96,6 +102,24 @@ class ZulipLocalizationsFr extends ZulipLocalizations {
   @override
   String get actionSheetOptionListOfTopics => 'List of topics';
 
+  @override
+  String get actionSheetOptionUnsubscribe => 'Unsubscribe';
+
+  @override
+  String unsubscribeConfirmationDialogTitle(String channelName) {
+    return 'Unsubscribe from $channelName?';
+  }
+
+  @override
+  String get unsubscribeConfirmationDialogMessageMaybeCannotResubscribe =>
+      'Once you leave this channel, you might not be able to rejoin.';
+
+  @override
+  String get unsubscribeConfirmationDialogConfirmButton => 'Unsubscribe';
+
+  @override
+  String get unsubscribeFailedTitle => 'Failed to unsubscribe';
+
   @override
   String get actionSheetOptionMuteTopic => 'Mute topic';
 

lib/generated/l10n/zulip_localizations_it.dart

@@ -88,6 +88,12 @@ class ZulipLocalizationsIt extends ZulipLocalizations {
   String get permissionsDeniedReadExternalStorage =>
       'Per caricare file, bisogna concedere a Zulip autorizzazioni aggiuntive nelle Impostazioni.';
 
+  @override
+  String get actionSheetOptionSubscribe => 'Subscribe';
+
+  @override
+  String get subscribeFailedTitle => 'Failed to subscribe';
+
   @override
   String get actionSheetOptionMarkChannelAsRead => 'Segna il canale come letto';
 
@@ -97,6 +103,24 @@ class ZulipLocalizationsIt extends ZulipLocalizations {
   @override
   String get actionSheetOptionListOfTopics => 'Elenco degli argomenti';
 
+  @override
+  String get actionSheetOptionUnsubscribe => 'Unsubscribe';
+
+  @override
+  String unsubscribeConfirmationDialogTitle(String channelName) {
+    return 'Unsubscribe from $channelName?';
+  }
+
+  @override
+  String get unsubscribeConfirmationDialogMessageMaybeCannotResubscribe =>
+      'Once you leave this channel, you might not be able to rejoin.';
+
+  @override
+  String get unsubscribeConfirmationDialogConfirmButton => 'Unsubscribe';
+
+  @override
+  String get unsubscribeFailedTitle => 'Failed to unsubscribe';
+
   @override
   String get actionSheetOptionMuteTopic => 'Silenzia argomento';
 

lib/generated/l10n/zulip_localizations_ja.dart

@@ -86,6 +86,12 @@ class ZulipLocalizationsJa extends ZulipLocalizations {
   String get permissionsDeniedReadExternalStorage =>
       'To upload files, please grant Zulip additional permissions in Settings.';
 
+  @override
+  String get actionSheetOptionSubscribe => 'Subscribe';
+
+  @override
+  String get subscribeFailedTitle => 'Failed to subscribe';
+
   @override
   String get actionSheetOptionMarkChannelAsRead => 'チャンネルを既読にする';
 
@@ -95,6 +101,24 @@ class ZulipLocalizationsJa extends ZulipLocalizations {
   @override
   String get actionSheetOptionListOfTopics => 'トピック一覧';
 
+  @override
+  String get actionSheetOptionUnsubscribe => 'Unsubscribe';
+
+  @override
+  String unsubscribeConfirmationDialogTitle(String channelName) {
+    return 'Unsubscribe from $channelName?';
+  }
+
+  @override
+  String get unsubscribeConfirmationDialogMessageMaybeCannotResubscribe =>
+      'Once you leave this channel, you might not be able to rejoin.';
+
+  @override
+  String get unsubscribeConfirmationDialogConfirmButton => 'Unsubscribe';
+
+  @override
+  String get unsubscribeFailedTitle => 'Failed to unsubscribe';
+
   @override
   String get actionSheetOptionMuteTopic => 'トピックをミュート';