Setting up MongoDB

Install MongoDB

JustIn requires a MongoDB server with replica sets in order to work. These instructions cover how to set up a local instance of MongoDB for testing and playing with the examples.

Download MongoDB Community Edition

Download MongoDB community edition

Create folder for storing data

On Mac, create a /data/mdata directory in your home directory ($ mkdir ~/data/mdata).

On Windows, create a \data\mdata directory at the top level of your C: drive, or (mkdir c:\data\mdata).

Run MongoDB

Enable MongoDB ReplicaSets

JustIn utilizes MongoDB's capability to subscribe to changes in the database, which requires the use of ReplicaSet (https://www.mongodb.com/docs/manual/replication/). To enable this feature, you will need to

1. run mongod with the --replSet option in one terminal

Mac OS

$ mongod --port 27017 --dbpath ~/data/mdata --replSet rs0 --bind_ip localhost

Windows

$ mongod --port 27017 --dbpath "c:\data\mdata" --replSet rs0 --bind_ip localhost

At this point you may see a bunch of errors complaining that replica sets are not initialized.

2. Use mongosh to enable Replica Sets

Leaving mongod running, open a separate terminal and do the following:

Both MacOS and Windows

$ mongosh
[mongosh prompt] > rs.initiate()
[mongosh prompt] > exit

Run mongod whenever running JustIn apps

Everything should be ready to go now, and you should see the error messages in the mongod terminal stop. mongod will need to stay running while any JustIn apps are running.

For information about other ways to install and run MongoDB, including running it as an always-available service, see the MongoDB documentation for your OS. Note that however you configure and run MongoDB you will need to be sure to enable ReplicaSets as discussed above.

Install MongoDB GUI (Optional)

If you want to see the data that JustIn creates and modifies in Mongo, you can use MongoDB compass for exploring the DB, or you can use mongosh from the command line.