Set Max Connection Limit as Env Variable

[AtulRajput01]

This PR addresses issue #18 add a new environment variable, POSTGRES_MAX_CONNECTIONS, to the docker-compose.yml file in order to configure the maximum number of database connections for the TimescaleDB service. By setting the value to 10, we can increase the maximum allowed connections to improve scalability and accommodate higher traffic.

[ChakshuGautam]

Hey @AtulRajput01 are we using PG or POSTGRES as the prefix for all these?

[AtulRajput01]

@ChakshuGautam yes sir, we are using 'POSTGRES' as the prefix for all these variables.

[jayanth-kumar-morem]

Hi @AtulRajput01 ,

To ensure this feature works as expected, I recommend adding a smoke test to verify the maximum number of database connections. Here's a rough idea of how you could approach this:

1. Start the Docker services with the new environment variable set.
2. Connect to the PostgreSQL database and check the current max_connections setting using the SQL command SHOW max_connections;. This should return the value set in the POSTGRES_MAX_CONNECTIONS environment variable.
3. Try to open more connections than the limit set. PostgreSQL should start refusing new connections once the limit is reached.

This test will help us confirm that the POSTGRES_MAX_CONNECTIONS environment variable is correctly setting the maximum number of database connections.

[AtulRajput01]

I have made the changes accordingly. I have updated the value of POSTGRES_MAX_CONNECTIONS 10 to 100.

[jayanth-kumar-morem]

Can you add the test to the workflow?

[AtulRajput01]

Can you add the test to the workflow?

hi @jayanth-kumar-morem , Added a smoke test to verify the maximum number of database connections

[jayanth-kumar-morem]

You haven't rebased your updates on the new changes on the repo. Please rebase it properly and here's a sample on how it needs to be tested.

        PGPASSWORD=$POSTGRES_PASSWORD psql -h localhost -U $POSTGRES_USER -d postgres -c "SHOW max_connections;"
        if [ "$(PGPASSWORD=$POSTGRES_PASSWORD psql -h localhost -U $POSTGRES_USER -d postgres -c "SHOW max_connections;" | grep -oP '(?<=row )[0-9]+')" -ne "$POSTGRES_MAX_CONNECTIONS" ]; then
          echo "Max connections is not set correctly!"
          exit 1
        fi

[jayanth-kumar-morem]

1. squash multiple similar commits
2. Default max connections in Postgresql is 100. Please change it to let's say 10 in the docker-compose and smoke tests. If the smoke tests pass when we pass 10 from docker-compose only, we can verify that we are able to modify the max connections from the env variable you added.