Execution order of dependencies

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Example Code

import uvicorn as uvicorn
from fastapi import FastAPI, Depends

app = FastAPI()


def dep1():
    print('1')


def dep2():
    print('2')


@app.get('/test', dependencies=[Depends(dep1), Depends(dep2)])
def test():
    return 'test'


if __name__ == '__main__':
    uvicorn.run("main:app", host="127.0.0.1", port=8008, reload=True, debug=True)

Description

By running the above code the output is

1
2

Is the execution order of dependencies always the declared order? I haven’t found anything in the docs regarding the order of the dependencies.

Operating System

Linux

Operating System Details

No response

FastAPI Version

0.73.0

Python Version

3.10.6

Additional Context

No response

[Soerboe]

@imacat The order of the elements in a list is guaranteed by python. A list is an ordered collection. Please, check your statements before posting.

However, FastAPI could choose to reorder the Depends() in the list for some reason. I want to know whether FastAPI would do this or not.

[imacat]

I suppose the order is from left to right. That means, dep1, and then dep2. However, the order is not guaranteed. And the order is dealt with by the Python compiler, not FastAPI.