Class for connecting to database

[codeforpdx]

Class for connecting to database

[wittejm]

Possibly naive question: wondering if passing the connection info from outside the wrapper object is the way to go, especially if that information is just getting picked up from env variables or an external file. If the following env variables are already defined,

PGHOST=recordexpungpdx_db 
PGUSER=docker 
PGPORT=5432
PGDATABASE=record_expunge

then you can get the connection object with

import  psycopg2
conn = psycopg2.connect(“”) 
cur = conn.cursor()

and no extra arguments. Or else the values could be provided inside the Database wrapper code , e.g.

conn = pyscopg2.connect("dbname=record_expunge user=docker port=5432 host=recordexpungpdx_db")
cur = conn.cursor()

Is there a reason not to use these approaches?

[maxkwallace]

@wittejm this is a good question about separation of concerns: we need to get the credentials from the environment somewhere, so what part of the code should be responsible for doing that?

AFAIK Erik is currently working on this so I will defer to him for the actual implementation.

But my preference is to use your second approach and pass the credentials in. Environment variables are global variables. If we access them in multiple places in our code it can be difficult to draw a clear boundary between our app and its environment. The best practice here is to only access environment variables in one place, and create one or more configuration objects to pass that data around in our code.

[wittejm]

closing; Database connectivity was added some time ago.