[PYTHON] A less likely misunderstanding about how to specify a handler for a zip uploaded with Lambda

• I feel like I wasted about half a day by fundamentally misunderstanding how to set the handler, so I will keep a record with my own caution.

Conclusion

Since the Lambda handler specification method is in the format file-name.function-name,

• Wrong: path.to.module.handler
• Correct: path / to / module.handler

Work record

What I wanted to do

For small services, I wanted to specify a zip version of a set of Lambda functions when creating the function.

Folder structure

+ attakei/
  + __init__.py
  + models.py
  + handlers.py 

Contents of the file (part)

attakei/handlers.py

def get_articles(event, context):
    return {}

def search_by_tags(event, context):
    return {"""something"""}

I want to manage the function as a set by specifying various handlers like attakei.handlers.get_articles when creating the Lambda function with the configuration like.

I can't do it for some reason

In this state, create a zip according to the AWS rules and upload it to S3 → If you specify a handler in the above format, it will not work at all when executing Test. Such a log keeps appearing.

Unable to import module 'attakei.handlers': No module named attakei.handlers

Try & error

A list of things I tried to reach the above conclusion

• Upload using lambda-upload ... NG
• Prepare main.py and call ʻattakei.handlers.get_articles` in the function in main ... OK
• Prepare main.py, write only from attakei.handler import get_articles in main, and register main.get_articles as a handler ... OK

Around here, I felt like "What is this?" Document Go and solve the problem. You have to read the document properly

complaints

When defining a console command when creating a python package, it is described as module path: function name, so it seems that my brain was stagnant because I completely turned my consciousness to that. However, I personally appreciate it if you matched this format ...