microservices-setup.md

Microservices Setup

{% hint style="info" %} The feature is released for General Availability on the Enterprise Edition v4.0. {% endhint %}

{% hint style="info" %} New in version 3.8. {% endhint %}

Pre-requisites

• NATS
  • Please refer to NATS Docker installation on how to deploy NATS
• MongoDB
  • Storage Engine needs to be WiredTiger:
    • Change Standalone to WiredTiger
• Rocket.Chat
  • The setting Use REST instead of WebSocket for Meteor calls under Admin > General > REST API, must be enabled.

The following environment variables should be set for Rocket.Chat services as well:

Variable	Value	Description
TRANSPORTER	nats://nats:4222	NATS address
DISABLE_DB_WATCH	true	Disables internal DB watcher and rely on mongodb-stream-hub
DISABLE_PRESENCE_MONITOR	true	Disables presence monitoring and rely on the presence-service
INTERNAL_SERVICES_ONLY	true	Do not run external services on rocket.chat process

Micro Services

Rocket.Chat microservices are composed of a few Docker containers:

Accounts

Responsible for user authentications

docker run \
--name accounts-service \
-e MONGO_URL=mongodb://mongo/rocketchat?replicaSet=rs01 \
-e TRANSPORTER=nats://nats:4222 \
rocketchat/account-service:latest

Authorization

Responsible for the validation of access to features

docker run \
--name authorization-service \
-e MONGO_URL=mongodb://mongo/rocketchat?replicaSet=rs01 \
-e TRANSPORTER=nats://nats:4222 \
rocketchat/authorization-service:latest

DDP Streamer

Web socket interface between server and clients

docker run \
--name ddp-streamer \
-e MONGO_URL=mongodb://mongo/rocketchat?replicaSet=rs01 \
-e TRANSPORTER=nats://nats:4222 \
rocketchat/ddp-streamer-service:latest

{% hint style="info" %} DDP Streamer should be scaled from the beginning. (One per 500 concurrent users should be good enough) {% endhint %}

MongoDB Stream Hub

{% hint style="danger" %} Can not be scaled to multiple containers {% endhint %}

Receives real-time data from MongoDB and emits that data to the system.

docker run \
--name mongodb-stream-hub \
-e MONGO_URL=mongodb://mongo/rocketchat?replicaSet=rs01 \
-e TRANSPORTER=nats://nats:4222 \
rocketchat/stream-hub-service:latest

Presence (Optional)

Controls and update users' presence status.

{% hint style="success" %} In a situation where you have a huge amount of data/users, you can get away with not running it to reduce the traffic of presence processing. If you are not running it, the user's online/offline status and notification will not work properly. {% endhint %}

docker run \
--name presence-service \
-e MONGO_URL=mongodb://mongo/rocketchat?replicaSet=rs01 \
-e TRANSPORTER=nats://nats:4222 \
rocketchat/presence-service:latest

Environment variables common to all services

Set the following environment variables to enable Prometheus metrics:

Variable	Default	Description
MS_METRICS	false	Enable Prometheus metrics endpoint
MS_METRICS_PORT	9458	Port of Prometheus metrics endpoint

Reverse proxy

Once all services are up and running the web socket connections should be targeted to ddp-streamer containers, the configuration depends on the reverse proxy you have set up, but you need to change the following routes:

• /sockjs
• /websocket

If using Kubernetes, an Ingress like the following can be used:

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: ddp-streamer
spec:
  rules:
  - host: your-hostname.rocket.chat
    http:
      paths:
      - backend:
          serviceName: ddp-streamer
          servicePort: 3000
        path: /(sockjs|websocket)

Summary:

To summarize it:

1. You just need to deploy the reverse proxy to split the communication.
2. Run all the above services pointing to the NATS and the MongoDB.
3. Deploy NATS.
4. Run Rocket.Chat according to the above-mentioned variables.