moto s3 using AWS_ENDPOINT_URL from .env

problem

In my Python project, I'm uploading files to AWS S3 using their boto3 library, with code that starts like:

client = boto3.client("s3", region_name=region, endpoint_url=endpoint_url)

I'm providing here the endpoint_url, as locally this points to LocalStack configured through an environment variable AWS_ENDPOINT_URL in my .env file.

To unit test this I'm using the moto library, which helps with mocking AWS services. I have a unit test method decorated with the @mock_s3 attribute and inside it I'm first creating a bucket, as per their documentation:

s3 = boto3.resource("s3")
s3.create_bucket(Bucket="test-bucket")

Because of the mocking attribute, this code is actually intercepted by moto.

I noticed that this unit test sometimes fails. Investigating this, I realized that it fails when my LocalStack Docker container is stopped, which lead me to the fact that the code is actually trying to create the bucket using the environment variable AWS_ENDPOINT_URL that I have configured in my .env file.

Now that's a serious problem, as I want the unit test to be independent and NOT use that AWS_ENDPOINT_URL.

solution

After some debugging and things that I tried, I managed to fix this by setting that environment variable to empty string from the unit test code, so before the code above I added:

os.environ["AWS_ENDPOINT_URL"] = ""

moto do have advice along these lines in their documentation: https://docs.getmoto.org/en/latest/docs/getting_started.html#how-do-i-avoid-tests-from-mutating-my-real-infrastructure

, but this variable, AWS_ENDPOINT_URL, is not covered there.

Gravatar
Author: Dan Dumitru
Last Edit: October 24, 2023
Last Edit October 24, 2023
Created October 24, 2023
Views 12
Tags
Python
AWS

Join us!

Do you like this website?

Bookmark it and come back here to write a post yourself when you run into something shareable.

Early collaborators will get to own a part of the project (5 to 20%)... >> read more

Your Comment

Feel free to post additional info or improvement suggestions.
preview
Optional, never shown, displays gravatar.

Formatting Tips

This editor uses Markdown to easily add code in your posts.

Triple backticks for full line(s) of code (or indent 4 spaces)

```
let foo = 'bar';
```

[link text](http://a.com)

*italic* **bold**

More Tips