feat: added DatabaseManager that connects to DB

[otomn]

Description

• Creates a database manager that connects with the Postgres database

Checklist

• [x] I have written unit tests for the code I added (sort of)

QA Steps

Production docker compose setting

1. Go to the root directory
2. Copy the .env.template to .env
3. Run the following commands

   npm run clean:ci
   npm install
   npm run docker:build
   npm run docker:up

4. Verify the following log is printed:

   backend-local | 
   backend-local | > @dateam/backend@1.0.0 start
   backend-local | > node ./build/Server.js
   backend-local | 
   backend-local | {
   backend-local |   host: 'postgres',
   backend-local |   port: 5432,
   backend-local |   database: 'dateam',
   backend-local |   user: 'dateam',
   backend-local |   password: 'dateam'
   backend-local | }
   backend-local | 18:56:33 connect(dateam@dateam); useCount: 0
   backend-local | 18:56:33 disconnect(dateam@dateam)
   backend-local | 18:56:33 connect(dateam@dateam); useCount: 0
   backend-local | 18:56:33 select count(*) from item
   backend-local | 18:56:34 disconnect(dateam@dateam)
   backend-local | { count: '0' }

Local development setting

1. In .env, set DB_HOST=localhost
2. Go to backend folder
3. Run the following commands

   rm -rf dbdata
   docker rm pgdb # may fail, but doesn't matter
   docker create --name pgdb \
   -e POSTGRES_USER=dateam \
   -e POSTGRES_PASSWORD=dateam \
   -e PGDATA=/var/lib/postgresql/data/pgdata \
   -v "$(PWD)/dbdata":/var/lib/postgresql/data \
   -v "$(PWD)/src/db/DBInitSQL":/docker-entrypoint-initdb.d \
   -p 5432:5432 \
   postgres:alpine
   docker start pgdb
   docker logs --follow pgdb

4. Wait until you see database system is ready to accept connections
5. Run node build/Server.js
6. Verify the following log is printed

   node build/Server.js
   development
   {
   host: 'localhost',
   port: 5432,
   database: 'dateam',
   user: 'dateam',
   password: 'dateam'
   }
   14:09:46 connect(dateam@dateam); useCount: 0
   14:09:46 select count(*) from item
   14:09:46 connect(dateam@dateam); useCount: 0
   14:09:46 disconnect(dateam@dateam)
   14:09:46 disconnect(dateam@dateam)
   { count: '0' }

[otomn]

@umar-ahmed Auto test is failing due to database not setup. Any solution?

[umar-ahmed]

@umar-ahmed Auto test is failing due to database not setup. Any solution?

Not sure why frontend build is failing, maybe try resetting package-lock.json and running npm install from root again.

In terms of the backend tests, there are two options:

• If we're only testing the API handlers in the backend unit tests, you can provide a mock implemenation of the data access layer
• If you want to add integration tests, I've heard of 2 ideas (but have never implemented it myself):
  • Spin up a Postgress instance when running backend tests using Docker
  • Swap out the database with a SQLite one (may introduce incompatibilities since SQLite may have different types and engine)

[DiademShoukralla]

QA:

Production Docker Compose settings

Verify the log output:

❓ Missing some expected output

backend-local | 18:56:33 connect(dateam@dateam); useCount: 0
backend-local | 18:56:33 select count(*) from item
backend-local | 18:56:34 disconnect(dateam@dateam)
backend-local | { count: '0' }

Also frontend-local did not start up. Not sure if the discrepancies are related

Local Development settings

❓ Same as above.. missing some expected output

@otomn For the most part, seems good, however some expected output is missing in both cases (the last 4 lines)

[otomn]

In the previous commit, I deleted the test query. I have added it back because we need it to see if the database schema is setup properly or not.

[otomn]

Test instruction

.env.template is updated, update the local .env before running the test The rest of the steps are the same

Expected output for docker test:

backend-local | 
backend-local | > @dateam/backend@1.0.0 start
backend-local | > node ./build/Server.js
backend-local | 
backend-local | {
backend-local |   host: 'postgres',
backend-local |   port: 5432,
backend-local |   database: 'dateam',
backend-local |   user: 'dateam',
backend-local |   password: 'dateam'
backend-local | }
backend-local | 21:22:42 connect(dateam@dateam); useCount: 0
backend-local | 21:22:42 SELECT count(*) FROM item
backend-local | 21:22:42 disconnect(dateam@dateam)
backend-local | Dabase is setup

Expected output for local test:

node build/Server.js
{
  host: 'localhost',
  port: 5432,
  database: 'dateam',
  user: 'dateam',
  password: 'dateam'
}
16:24:01 connect(dateam@dateam); useCount: 0
16:24:01 SELECT count(*) FROM item
16:24:01 disconnect(dateam@dateam)
Dabase is setup

[otomn]

@PersonalCorrect please test again

[DiademShoukralla]

QA

Docker/Production Test

✔️ QA Pass

Local Test

❌ QA Fail: Error executing one of the queries Log:

[DiademShoukralla]

Hmm, I still keep getting the same error when doing the local test. I followed all steps listed (ensuring dbdata folder is deleted). The production/docker test still passes; this is only an issue with the local test.

Some things I noticed (which might help debugging?):

• My dbdata folder is consistently named "dbdata;C" not "dbdata"
• My pgdb container logs: Maybe the db is not being initialized properly?