Fixing Database Connection and Testing the Application in Docker Compose

rest-server | 2021/05/10 00:54:26 failed to initialise the store: pq: password authentication failed for user totoro rest-server | 2021/05/10 00:54:29 failed to initialise the store: pq: password authentication failed for user totoro rest-server | 2021/05/10 00:54:25 failed to initialise the store: pq: password authentication failed for user totoro rest-server | 2021/05/10 00:54:26 failed to initialise the store: pq: password authentication failed for user totoro rest-server | 2021/05/10 00:54:29 failed to initialise the store: pq: password authentication failed for user totoro rest-server exited with code 1 # ... omitted output ... ``` Because of the way you set up your deployment using `restart_policy`, the failing container is being restarted every 20 seconds. So, in order to fix the problem, you need to log in to the database engine and create the user. You've done it before in [Configure the database engine](#configure-the-database-engine). This isn't a big deal. All you have to do is to connect to CockroachDB instance and run the three SQL commands to create the database and the user, as described in [Configure the database engine](#configure-the-database-engine). So, log in to the database engine from another terminal: ```console $ docker exec -it roach ./cockroach sql --insecure ``` And run the same commands as before to create the database `mydb`, the user `totoro`, and to grant that user necessary permissions. Once you do that (and the example application container is automatically restarts), the `rest-service` stops failing and restarting and the console goes quiet. It would have been possible to connect the volume that you had previously used, but for the purposes of this example it's more trouble than it's worth and it also provided an opportunity to show how to introduce resilience into your deployment via the `restart_policy` Compose file feature. ### Testing the application Now, test your API endpoint. In the new terminal, run the following command: ```console $ curl http://localhost/ ``` You should receive the following response: ```json Hello, Docker! (0) ``` ### Shutting down To stop the containers started by Docker Compose, press `ctrl+c` in the terminal where you ran `docker compose up`. To remove those containers after they've been stopped, run `docker compose down`. ### Detached mode You can run containers started by the `docker compose` command in detached mode, just as you would with the `docker` command, by using the `-d` flag. To start the stack, defined by the Compose file in detached mode, run:

This section details how to fix the database connection issue in a Docker Compose setup by logging into the CockroachDB instance and creating the missing database and user. It also explains how the `restart_policy` ensures the container restarts automatically. Once the database is configured, the application should run without errors. Finally, it guides the user to test the API endpoint using `curl` and explains how to shut down the containers and run them in detached mode using the `-d` flag.