[ECO-5642] feat: add message editing support to channels

lib/src/main/java/io/ably/lib/realtime/ChannelBase.java

@@ -16,6 +16,7 @@
 import io.ably.lib.http.HttpUtils;
 import io.ably.lib.objects.RealtimeObjects;
 import io.ably.lib.objects.LiveObjectsPlugin;
+import io.ably.lib.rest.MessageEditsMixin;
 import io.ably.lib.rest.RestAnnotations;
 import io.ably.lib.transport.ConnectionManager;
 import io.ably.lib.transport.ConnectionManager.QueuedMessage;
@@ -32,6 +33,7 @@
 import io.ably.lib.types.Message;
 import io.ably.lib.types.MessageAnnotations;
 import io.ably.lib.types.MessageDecodeException;
+import io.ably.lib.types.MessageOperation;
 import io.ably.lib.types.MessageSerializer;
 import io.ably.lib.types.MessageVersion;
 import io.ably.lib.types.PaginatedResult;
@@ -100,6 +102,8 @@ public abstract class ChannelBase extends EventEmitter<ChannelEvent, ChannelStat
 
     @Nullable private final LiveObjectsPlugin liveObjectsPlugin;
 
+    private volatile MessageEditsMixin messageEditsMixin;
+
     public RealtimeObjects getObjects() throws AblyException {
         if (liveObjectsPlugin == null) {
             throw AblyException.fromErrorInfo(
@@ -1172,6 +1176,172 @@ else if(!"false".equalsIgnoreCase(param.value)) {
     private static final String KEY_UNTIL_ATTACH = "untilAttach";
     private static final String KEY_FROM_SERIAL = "fromSerial";
 
+    //region Message Edits and Deletes
+
+    /**
+     * Retrieves the latest version of a specific message by its serial identifier.
+     * <p>
+     * This method allows you to fetch the current state of a message, including any updates
+     * or deletions that have been applied since its creation.
+     *
+     * @param serial The unique serial identifier of the message to retrieve.
+     * @return A {@link Message} object representing the latest version of the message.
+     * @throws AblyException If the message cannot be retrieved or does not exist.
+     */
+    public Message getMessage(String serial) throws AblyException {
+        return messageEditsMixin.getMessage(ably.http, serial);
+    }
+
+    /**
+     * Asynchronously retrieves the latest version of a specific message by its serial identifier.
+     *
+     * @param serial The unique serial identifier of the message to retrieve.
+     * @param callback A callback to handle the result asynchronously.
+     * <p>
+     * This callback is invoked on a background thread.
+     */
+    public void getMessageAsync(String serial, Callback<Message> callback) {
+        messageEditsMixin.getMessageAsync(ably.http, serial, callback);
+    }
+
+    /**
+     * Updates an existing message using patch semantics.
+     * <p>
+     * Non-null fields in the provided message (name, data, extras) will replace the corresponding
+     * fields in the existing message, while null fields will be left unchanged.
+     *
+     * @param message A {@link Message} object containing the fields to update and the serial identifier.
+     *                Only non-null fields will be applied to the existing message.
+     * @param operation operation metadata such as clientId, description, or metadata in the version field
+     * @throws AblyException If the update operation fails.
+     */
+    public void updateMessage(Message message, MessageOperation operation) throws AblyException {
+        messageEditsMixin.updateMessage(ably.http, message, operation);
+    }
+
+    /**
+     * Updates an existing message using patch semantics.
+     * <p>
+     * Non-null fields in the provided message (name, data, extras) will replace the corresponding
+     * fields in the existing message, while null fields will be left unchanged.
+     *
+     * @param message A {@link Message} object containing the fields to update and the serial identifier.
+     *                Only non-null fields will be applied to the existing message.
+     * @throws AblyException If the update operation fails.
+     */
+    public void updateMessage(Message message) throws AblyException {
+        updateMessage(message, null);
+    }
+
+    /**
+     * Asynchronously updates an existing message.
+     *
+     * @param message A {@link Message} object containing the fields to update and the serial identifier.
+     * @param operation operation metadata such as clientId, description, or metadata in the version field
+     * @param listener A listener to be notified of the outcome of this operation.
+     * <p>
+     * This listener is invoked on a background thread.
+     */
+    public void updateMessageAsync(Message message, MessageOperation operation, CompletionListener listener) {
+        messageEditsMixin.updateMessageAsync(ably.http, message, operation, listener);
+    }
+
+    /**
+     * Asynchronously updates an existing message.
+     *
+     * @param message A {@link Message} object containing the fields to update and the serial identifier.
+     * @param listener A listener to be notified of the outcome of this operation.
+     * <p>
+     * This listener is invoked on a background thread.
+     */
+    public void updateMessageAsync(Message message, CompletionListener listener) {
+        updateMessageAsync(message, null, listener);
+    }
+
+    /**
+     * Marks a message as deleted.
+     * <p>
+     * This operation does not remove the message from history; it marks it as deleted
+     * while preserving the full message history. The deleted message can still be
+     * retrieved and will have its action set to MESSAGE_DELETE.
+     *
+     * @param message A {@link Message} message containing the serial identifier.
+     * @param operation operation metadata such as clientId, description, or metadata in the version field
+     * @throws AblyException If the delete operation fails.
+     */
+    public void deleteMessage(Message message, MessageOperation operation) throws AblyException {
+        messageEditsMixin.deleteMessage(ably.http, message, operation);
+    }
+
+    /**
+     * Marks a message as deleted.
+     * <p>
+     * This operation does not remove the message from history; it marks it as deleted
+     * while preserving the full message history. The deleted message can still be
+     * retrieved and will have its action set to MESSAGE_DELETE.
+     *
+     * @param message A {@link Message} message containing the serial identifier.
+     * @throws AblyException If the delete operation fails.
+     */
+    public void deleteMessage(Message message) throws AblyException {
+        deleteMessage(message, null);
+    }
+
+    /**
+     * Asynchronously marks a message as deleted.
+     *
+     * @param message A {@link Message} object containing the serial identifier and operation metadata.
+     * @param operation operation metadata such as clientId, description, or metadata in the version field
+     * @param listener A listener to be notified of the outcome of this operation.
+     * <p>
+     * This listener is invoked on a background thread.
+     */
+    public void deleteMessageAsync(Message message, MessageOperation operation, CompletionListener listener) {
+        messageEditsMixin.deleteMessageAsync(ably.http, message, operation, listener);
+    }
+
+    /**
+     * Asynchronously marks a message as deleted.
+     *
+     * @param message A {@link Message} object containing the serial identifier and operation metadata.
+     * @param listener A listener to be notified of the outcome of this operation.
+     * <p>
+     * This listener is invoked on a background thread.
+     */
+    public void deleteMessageAsync(Message message, CompletionListener listener) {
+        deleteMessageAsync(message, null, listener);
+    }
+
+    /**
+     * Retrieves all historical versions of a specific message.
+     * <p>
+     * This method returns a paginated result containing all versions of the message,
+     * ordered chronologically. Each version includes metadata about when and by whom
+     * the message was modified.
+     *
+     * @param serial The unique serial identifier of the message.
+     * @param params Query parameters for filtering or pagination (e.g., limit, start, end).
+     * @return A {@link PaginatedResult} containing an array of {@link Message} objects
+     *         representing all versions of the message.
+     * @throws AblyException If the versions cannot be retrieved.
+     */
+    public PaginatedResult<Message> getMessageVersions(String serial, Param[] params) throws AblyException {
+        return messageEditsMixin.getMessageVersions(ably.http, serial, params);
+    }
+
+    /**
+     * Asynchronously retrieves all historical versions of a specific message.
+     *
+     * @param serial The unique serial identifier of the message.
+     * @param params Query parameters for filtering or pagination.
+     * @param callback A callback to handle the result asynchronously.
+     */
+    public void getMessageVersionsAsync(String serial, Param[] params, Callback<AsyncPaginatedResult<Message>> callback) throws AblyException {
+        messageEditsMixin.getMessageVersionsAsync(ably.http, serial, params, callback);
+    }
+
+    //endregion
+
     /************************************
      * Channel history
      ************************************/
@@ -1278,6 +1448,7 @@ public void setOptions(ChannelOptions options) throws AblyException {
      */
     public void setOptions(ChannelOptions options, CompletionListener listener) throws AblyException {
         this.options = options;
+        this.messageEditsMixin = new MessageEditsMixin(basePath, ably.options, options, ably.auth);
         if(this.shouldReattachToSetOptions(options)) {
             this.attach(true, listener);
         } else {
@@ -1353,6 +1524,7 @@ else if(stateChange.current.equals(failureState)) {
             this,
             new RestAnnotations(name, ably.http, ably.options, options)
         );
+        this.messageEditsMixin = new MessageEditsMixin(basePath, ably.options, options, ably.auth);
     }
 
     void onChannelMessage(ProtocolMessage msg) {