Setup guide for FastAPI

This page guides you through the steps of configuring your FastAPI application to work with Apitally. If you don’t have an account yet, now would be a good time to sign up.

Once you’re done with this guide, you will be able to:

• Monitor traffic to your application on our simple dashboard
• Keep track of errors, response times and payload sizes
• Understand how individual API consumers use your application
• Monitor your application’s uptime and receive alerts when it’s down

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Create app

To get started, create a new app in the Apitally dashboard and select as your framework.

Here you can also configure the environments (e.g. prod and dev) for your app, or simply accept the defaults.

Take a note of the client ID displayed after submitting. You will need it in the next step.

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Add middleware

Next, install the Apitally client library in your project with the extra.

pip install "apitally[fastapi]"

Add the Apitally middleware to your FastAPI application and provide the client_id for your app. You’ll find the client_id on the Setup instructions page for your app in the Apitally dashboard, which is displayed immediately after creating the app.

from fastapi import FastAPI
from apitally.fastapi import ApitallyMiddleware

app = FastAPI()
app.add_middleware(
    ApitallyMiddleware,
    client_id="your-client-id",
    env="dev",  # or "prod" etc.
)

Deploy your application with these changes, or restart if you're testing locally.

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Identify consumers

In order to analyze API traffic by consumers in Apitally, your application must identify which consumers requests are coming from.

How you identify API consumers depends on your application and use case. If your application uses authentication, it would make sense to use the authenticated identity (e.g. username) as the consumer identifier.

To associate requests with consumers, set the consumer_identifier attribute on the request.state object. You could do this in a dependency or another middleware, for example.

from typing import Annotated
from fastapi import FastAPI, Depends, Request
from fastapi.security import OAuth2PasswordBearer

oauth2_scheme = OAuth2PasswordBearer(tokenUrl="token")

class User(BaseModel):
    username: str

async def get_current_user(token: Annotated[str, Depends(oauth2_scheme)]):
    user = fake_decode_token(token)
    return user

def identify_consumer(request: Request, current_user: Annotated[User, Depends(get_current_user)]):
    request.state.consumer_identifier = current_user.username

app = FastAPI(dependencies=[Depends(identify_consumer)])

The consumer identifier should be a string that uniquely identifies the consumer of the API, e.g. customer-123. Once the first request is received from a consumer, it will show up in the Apitally dashboard and you can assign a more descriptive name to it.