[CHA-6675] feat: add includeSoftDeletedChannel to getChannel

src/main/java/io/getstream/chat/java/models/Channel.java

@@ -622,6 +622,10 @@ public static class GetChannelRequestData {
     @JsonProperty("messages_id_around")
     private String messagesIdAround;
 
+    @Nullable
+    @JsonProperty("include_soft_deleted_channel")
+    private Boolean includeSoftDeletedChannel;
+
     public static class GetChannelRequest extends StreamRequest<ChannelGetResponse> {
       @NotNull private String channelType;
 
@@ -1761,7 +1765,9 @@ public static ChannelGetRequest getOrCreate(@NotNull String type) {
   /**
    * Creates a get channel request. The channel is never created: a missing, deleted or disabled
    * channel yields a 404, so this request doubles as an existence check. The messages of the
-   * channel are paged with the messagesId* parameters, which need state to be true.
+   * channel are paged with the messagesId* parameters, which need state to be true. Set
+   * includeSoftDeletedChannel to read a soft-deleted channel and the messages its deletion hid; its
+   * members are not returned.
    *
    * @param type the channel type
    * @param id the channel id

src/test/java/io/getstream/chat/java/ChannelTest.java

@@ -122,6 +122,42 @@ private List<String> messageIds(ChannelGetResponse response) {
     return response.getMessages().stream().map(Message::getId).collect(Collectors.toList());
   }
 
+  @DisplayName("Can get a soft-deleted channel and its messages")
+  @Test
+  void whenGettingSoftDeletedChannelWithInclude_thenReturnsChannelAndMessages() {
+    var channelId = RandomStringUtils.randomAlphabetic(12);
+    Assertions.assertDoesNotThrow(
+        () ->
+            Channel.getOrCreate(testChannel.getType(), channelId)
+                .data(
+                    ChannelRequestObject.builder()
+                        .createdBy(testUserRequestObject)
+                        .members(buildChannelMembersList())
+                        .build())
+                .request());
+
+    var first = sendMessageToChannel(channelId, "first");
+    var second = sendMessageToChannel(channelId, "second");
+
+    Assertions.assertDoesNotThrow(() -> Channel.delete(testChannel.getType(), channelId).request());
+
+    var notFound =
+        Assertions.assertThrows(
+            StreamException.class,
+            () -> Channel.getChannel(testChannel.getType(), channelId).state(true).request());
+    Assertions.assertEquals(404, notFound.getResponseData().getStatusCode());
+
+    var response =
+        Assertions.assertDoesNotThrow(
+            () ->
+                Channel.getChannel(testChannel.getType(), channelId)
+                    .state(true)
+                    .includeSoftDeletedChannel(true)
+                    .request());
+    Assertions.assertNotNull(response.getChannel().getDeletedAt());
+    Assertions.assertEquals(Arrays.asList(first, second), messageIds(response));
+  }
+
   @DisplayName("Get channel does not create a missing channel")
   @Test
   void whenGettingMissingChannel_thenNotFound() {