added old method

back/methods/chat/sendMessage.js

@@ -0,0 +1,30 @@
+module.exports = Self => {
+    Self.remoteMethodCtx('sendMessage', {
+        description: 'Send a RocketChat message',
+        accessType: 'WRITE',
+        accepts: [{
+            arg: 'to',
+            type: 'String',
+            required: true,
+            description: 'user (@) or channel (#) to send the message'
+        }, {
+            arg: 'message',
+            type: 'String',
+            required: true,
+            description: 'The message'
+        }],
+        returns: {
+            type: 'Object',
+            root: true
+        },
+        http: {
+            path: `/sendMessage`,
+            verb: 'POST'
+        }
+    });
+
+    // FIXME: Deprecate this method #2019
+    Self.sendMessage = async(ctx, to, message) => {
+        return Self.send(ctx, to, message);
+    };
+};

back/models/chat.js

@@ -1,4 +1,5 @@
 module.exports = Self => {
     require('../methods/chat/send')(Self);
+    require('../methods/chat/sendMessage')(Self);
     require('../methods/chat/sendCheckingPresence')(Self);
 };