Add support for slash commands

js/controller.js

@@ -164,6 +164,25 @@ function sendMessage(endpoint, channel_id, message) {
 	//});
 }
 
+async function executeSlashCommand(endpoint, channel_id, command) {
+	const client = mm_client.get(endpoint);
+	const response = await client.executeSlashCommand(channel_id, command);
+
+	if (
+		response.responseJson &&
+		response.responseJson.text &&
+		response.responseJson.response_type !== "in_channel"
+	) {
+		pubsub.publish("MESSAGES_NEW", {
+			endpoint,
+			channel_id,
+			create_at: (new Date()).getTime(),
+			user_id: client.me.id,
+			message: "(only visible to you) " + response.responseJson.text
+		});
+	}
+}
+
 function markChannelAsRead(client, channel) {
 	return client.markChannelRead(channel.id);
 }
@@ -172,11 +191,22 @@ function checkKeyPress(event) {
 	// Battle tested for many years in several browsers
 	if ((event.keyCode === event.DOM_VK_RETURN || event.keyCode === 13 || event.keyCode === 10 || event.key === "Enter" || event.keyIdentifier === "U+000A") && !event.shiftKey && !event.ctrlKey) {
 		if (byId("compose").value.length > 0) {
-			sendMessage(
-				byId("channel_contents").dataset["server"],
-				byId("channel_contents").dataset["id"],
-				byId("compose").value
-			);
+			let message = byId("compose").value;
+
+			if (message[0] === "/") {
+				executeSlashCommand(
+					byId("channel_contents").dataset["server"],
+					byId("channel_contents").dataset["id"],
+					message
+				);
+			} else {
+				sendMessage(
+					byId("channel_contents").dataset["server"],
+					byId("channel_contents").dataset["id"],
+					message
+				);
+			}
+
 			byId("compose").value = "";
 		}
 		return true;

js/mm_client.js

@@ -155,6 +155,10 @@ class MattermostClient {
 		});
 	}
 
+	executeSlashCommand(channel_id, command) {
+		return this.post("/commands/execute", {channel_id, command});
+	}
+
 	getUsers() {
 		if (!this.users) {
 			this.users = this.paginatedGet("/users", {}).then(users => {

js/util.js

@@ -72,6 +72,11 @@ function arrayToHashmap(array, key) {
 }
 
 
+function startsWith(string, start) {
+	return string.slice(0, start.length) == start;
+}
+
+
 function padLeft(input, width, padding=" ") {
 	text = input + "";
 	while (text.length < width) {