Setup App Database & connect to database

In our example we have the posts that will have to be added to a table in our Database

• The posts table will have to have the following columns:

• Also added 2 mock posts to the database

To connect Python to our Database

• We will need a Postgres Driver

• There are multiple libraries that are able to do that but we ill use the Psycopg Library

• To set this up for Psycopg3 use this documentation

• Basic module usage will help you set up the Database connection

To connect to the database we need to set up the following code

import psycopg

try:
    conn = psycopg.connect("dbname=fastapi user=postgres password=Password1")
    cursor = conn.cursor()
    print("Database connection successful")

except Exception as error:
    print("Connecting to database failed")
    print("Error: ", error)

• This should either connect or return the error that was raised

If there is any python code that can fail, it is best to use the try/except block in order to not break the code

• The main problem with the above code is that if the database is not reachable, there is no point in having our server up

• One solution would be to add the whole thing into a while loop

while True:

    try:
        conn = psycopg.connect("dbname=fastapi user=postgres password=Password1")
        cursor = conn.cursor()
        print("Database connection successful")
        break

    except Exception as error:
        print("Connecting to database failed")
        print("Error: ", error)
        time.sleep(2)

• We will break out of the loop if the connection is successful

• If the connection does not work, it will wait 2 seconds and restart the loop

Hint: We have hardcoded our database credentials in our code

This is really bad practice, but as we are learning, this is fine for now.