[CHAT-1108] slow mode (#404)

* wip on cool down

* improve tests

* align with feature docs

* run all tests

* add ts definitions

* simplify

* move to TS

src/channel.ts

@@ -469,6 +469,49 @@ export class Channel<
     return data;
   }
 
+  /**
+   * enableSlowMode - enable slow mode
+   *
+   * @param {coolDownInterval<number>} coolDownInterval the cooldown interval in seconds
+   * @return {Promise<UpdateChannelAPIResponse<ChannelType, AttachmentType, MessageType, ReactionType, UserType>>} The server response
+   */
+  async enableSlowMode(coolDownInterval: number) {
+    const data = await this.getClient().post<
+      UpdateChannelAPIResponse<
+        ChannelType,
+        AttachmentType,
+        MessageType,
+        ReactionType,
+        UserType
+      >
+    >(this._channelURL(), {
+      cooldown: coolDownInterval,
+    });
+    this.data = data.channel;
+    return data;
+  }
+
+  /**
+   * disableSlowMode - disable slow mode
+   *
+   * @return {Promise<UpdateChannelAPIResponse<ChannelType, AttachmentType, MessageType, ReactionType, UserType>>} The server response
+   */
+  async disableSlowMode() {
+    const data = await this.getClient().post<
+      UpdateChannelAPIResponse<
+        ChannelType,
+        AttachmentType,
+        MessageType,
+        ReactionType,
+        UserType
+      >
+    >(this._channelURL(), {
+      cooldown: 0,
+    });
+    this.data = data.channel;
+    return data;
+  }
+
   /**
    * delete - Delete the channel. Messages are permanently removed.
    *

test/slow_mode.js

@@ -0,0 +1,125 @@
+import uuidv4 from 'uuid/v4';
+import { getTestClient, getTestClientForUser } from './utils';
+import chai from 'chai';
+import chaiAsPromised from 'chai-as-promised';
+import { sleep } from '../src/utils';
+
+const expect = chai.expect;
+chai.use(chaiAsPromised);
+
+describe('channel slow mode', function() {
+	const moderator = 'mod-' + uuidv4();
+	const admin = 'admin-' + uuidv4();
+	const member = 'member' + uuidv4();
+	let ssClient;
+	let moderatorClient;
+	let adminClient;
+	let memberClient;
+	let channel;
+	before(async function() {
+		ssClient = await getTestClient(true);
+		await ssClient.upsertUsers([
+			{ id: admin, role: 'admin' },
+			{ id: member },
+			{ id: moderator },
+		]);
+		moderatorClient = await getTestClientForUser(moderator);
+		memberClient = await getTestClientForUser(member);
+		adminClient = await getTestClientForUser(admin);
+		channel = ssClient.channel('messaging', uuidv4(), {
+			members: [member, moderator],
+			created_by_id: admin,
+		});
+		await channel.create();
+		await channel.addModerators([moderator]);
+	});
+
+	it('server side auth clients should be able to change cooldown', async function() {
+		const resp = await channel.enableSlowMode(3);
+		expect(resp.channel.cooldown).to.be.equal(3);
+	});
+
+	it('moderator users should be able to change cooldown', async function() {
+		const resp = await moderatorClient
+			.channel('messaging', channel.id)
+			.enableSlowMode(2);
+		expect(resp.channel.cooldown).to.be.equal(2);
+	});
+
+	it('admin users should be able to change cooldown', async function() {
+		const resp = await adminClient.channel('messaging', channel.id).enableSlowMode(1);
+		expect(resp.channel.cooldown).to.be.equal(1);
+	});
+
+	it('regular members cannot change cooldown', async function() {
+		const p = memberClient.channel('messaging', channel.id).enableSlowMode(1);
+		await expect(p).to.be.rejectedWith(
+			'StreamChat error code 17: UpdateChannel failed with error: "cooldown settings can only be updated by channel moderator or admin"',
+		);
+	});
+
+	it('an error must be returned for regular users when sending messages under coolDown period', async function() {
+		const ch = memberClient.channel('messaging', channel.id);
+		await ch.query();
+		let resp = await ch.sendMessage({ text: 'hi' });
+		expect(resp.message).to.not.be.undefined;
+
+		// second message should return an error (under cooldown period)
+		await expect(ch.sendMessage({ text: 'hi' })).to.be.rejectedWith(
+			`StreamChat error code 60: SendMessage failed with error: "user ${member} is not allowed to send messages on channel ${ch.cid} under cool down period(1s)"`,
+		);
+		// wait for cool down to complete
+		await sleep(1000);
+
+		resp = await ch.sendMessage({ text: 'hi' });
+		expect(resp.message).to.not.be.undefined;
+	});
+
+	it('cool down doesnt apply to moderators', async function() {
+		// send messages with moderator
+		const modChannel = moderatorClient.channel('messaging', channel.id);
+		for (let i = 0; i < 5; i++) {
+			const resp = await modChannel.sendMessage({ text: 'hi' });
+			expect(resp.message).to.not.be.undefined;
+		}
+	});
+
+	it('cool down doesnt apply to admin users', async function() {
+		// send messages with admin
+		const adminChannel = adminClient.channel('messaging', channel.id);
+		for (let i = 0; i < 5; i++) {
+			const resp = await adminChannel.sendMessage({ text: 'hi' });
+			expect(resp.message).to.not.be.undefined;
+		}
+	});
+
+	it('cool down doesnt apply to server side auth', async function() {
+		// send messages with server side auth
+		for (let i = 0; i < 5; i++) {
+			const resp = await channel.sendMessage({ text: 'hi', user_id: admin });
+			expect(resp.message).to.not.be.undefined;
+		}
+	});
+
+	it('disable slow mode', async function() {
+		const resp = await channel.disableSlowMode();
+		expect(resp.channel.cooldown).to.be.undefined;
+	});
+
+	it('creating a channel with custom field cooldown should fail', async function() {
+		const ch = ssClient.channel('messaging', uuidv4(), {
+			members: [member, moderator],
+			created_by_id: admin,
+			cooldown: 2,
+		});
+		await expect(ch.create()).to.be.rejectedWith(
+			'StreamChat error code 4: GetOrCreateChannel failed with error: "data.cooldown is a reserved field"',
+		);
+	});
+
+	it('update the channel with custom field cooldown return an error', async function() {
+		await expect(channel.update({ cooldown: 1 })).to.be.rejectedWith(
+			'StreamChat error code 4: UpdateChannel failed with error: "data.cooldown is a reserved field"',
+		);
+	});
+});