Since MongoDB 3.6 change streams are supported. These change streams enable applications to stream real-time data changes.
They can come in handy if you want to listen to changes in data in a collection and relay (or consume) them instantly in your live application. Have the following setup to be able to test the code snippets in this repo.
Ensure you have the following installed before attempting to run this project locally.
Having higher versions that the ones required here would be an added advantage.
Running MongoDB
Create a .env file in the root of this project and add the following:
# NOTE: r1 is the name you choose to give to your replica set (as shown below).
MONGODB_URI='mongodb://localhost/?replSet=r1'Ensure MongoDB is running on your PC:
Open a terminal and type: mongo to confirm whether it's running or not.
Check this tutorial to learn more about MongoDB.
Start your DB in a Replica Mode:
# you can manually pass the DB path here or not
# Give your replica set a name: `r1`
mongod --dbpath /data/db --replSet r1Create a replica set
Once you have the DB running on a Replica Mode, open a new terminal and run Mongo Shell:
# type the following and press ENTER
mongo
# initialize DB replica set mode
rs.initiate()After running rs.initiate() your DB will officially launch in a replica mode. You should be able to see a shell starting with: r1:SECONDARY. Press ENTER and you're going to see: r1:PRIMARY.
After cloning the repo to your machine, install dependencies with: yarn install
Open a new terminal and run: yarn listen
You won't see any DB logs just yet. Navigate back to the Mongo Shell and insert arbitrary data to the demo collection on our test DB:
# inserting data into MONGODB
# check the running
db
# then use `test` db
use test
# insert data
db.demo.insert({ name: 'Harrison' })Go back to the terminal running: yarn listen and behold!
Drop me an email if you don't see anything or check out the screencast under assets. You may need to download it for now.