API-The-Cozy-Whisker

A restaurant API for The Cozy Whisker Cat Café.

Running the API Node App with Docker

This guide walks you through the process of setting up and running your API Node application with Docker, including handling a PostgreSQL database container.

Prerequisites

• Docker installed on your system
• Windows Subsystem for Linux (WSL) set up for Windows users
• Node.js and npm installed for running the Node application

Instructions

Setting Up Your Node Application

1. Open a WSL terminal.

2. Navigate to your project directory where the package.json is located.

3. Run your Node application:

   npm start

Setting Up PostgreSQL with Docker

1. Open a second WSL terminal.

2. Build your PostgreSQL Docker image:

   docker build -t postgres_image .

3. Run your PostgreSQL container:

   docker run --name postgresql -p 5432:5432 postgres_image

4. After you run your image you'll see the PostgreSQL logs, when you for somewhat reason you stop it using Ctrl + C in the bash, you can run it again, as explained below, but you won't be able to see the logs again, so you will have to do:

      docker logs -f CONTAINER_ID

   The flag -f keeps the PostgreSQL logs on screen, so you don't have to be doing docker logs CONTAINER_ID every time you want to see the database logs.

Managing Your PostgreSQL Container

• Check Running Containers: If your container stops and

  docker ps

  shows no running containers, follow these steps to restart it:

  3.1 List all containers (stopped and running):

  docker ps -a

  3.2. Find the Process ID (CONTAINER ID) of your PostgreSQL container.

  3.3. Restart the container:

  docker start PROCESSID
  

  3.4. Verify it's running:

  docker ps
  

Commenting Out Database Creation:

• After the initial database creation, you may want to comment out the CREATE DATABASE line in your Docker setup to prevent errors on subsequent starts.

• Dropping a Database:

  • Ensure your PostgreSQL container is running, then execute:

  docker exec PROCESSID dropdb -U dbadmin DATABASENAME

Starting Over with a New Docker Setup

• To remove your current Docker setup and start fresh:

  1. List all containers:

  docker ps -a

  2. Copy the Process ID (CONTAINER ID) of the container you wish to remove.

  3. Stop the container:

  docker stop PROCESSID

  4. Remove the container:

  docker rm PROCESSID

  5. You can now proceed with the build process again as described in the setup instructions.

Handling PostgreSQL Database Operations in Docker

This guide provides steps to follow if you encounter errors like "CANNOT DROP DATABASE" or "DATABASE ALREADY EXISTS" when working with PostgreSQL inside a Docker container.

Steps to Resolve Common Errors

1. List All Containers

   Use this command to list all Docker containers, including their IDs and statuses:

   docker ps -a

2. Select the Container ID

   Identify and note down the container ID of the PostgreSQL container from the list provided by the previous command.

3. Start the Container (If Not Running)

   If the container is not already running, start it with the following command, replacing containerID with your actual container ID:

   docker start containerID

4. Access the Container's Bash Shell

   Use this command to enter the bash shell of your container:

   docker exec -it containerID bash

5. Inside the Bash Shell

   Once inside the container's bash shell, execute the following command to create a temporary database. This step is necessary for performing certain operations like dropping another database, as you cannot drop a database while connected to it.

   createdb -U dbadmin tempdb

6. Execute the Drop Database Command

   Exit the bash shell to return to your host machine's command line. Then, execute the following command to drop the desired database, in this case, the_cozy_whisker:

   docker exec -it containerID psql -U dbadmin -d tempdb -c "DROP DATABASE IF EXISTS the_cozy_whisker;" -W

   When prompted, enter the password for the dbadmin user.

Notes

• Replace containerID with the actual ID of your Docker container.
• Replace the_cozy_whisker with the name of the database you wish to drop, if different.
• These instructions assume dbadmin as the PostgreSQL user. Adjust accordingly if you use a different username.

Conclusion

Follow these steps carefully to ensure a smooth setup and operation of your API Node app with Docker. Remember to substitute PROCESSID, dbadmin, and DATABASENAME with your actual process ID, database admin username, and database name, respectively.