@app.get

Learn to define routes with @app.get("/path").

@app.get

The @app.get("/path") decorator binds a GET route to a function. When a request hits that path, FastAPI calls the function and turns its return value into a response.

@app.get("/merhaba")
def merhaba():
    return {"msg": "selam"}

The path string is the path part of the URL (e.g. /merhaba). If the return value is a dict, FastAPI responds with structured data.

Return value

When a route function returns a dict, FastAPI turns it into a structured-data response. Lists, numbers and strings are converted similarly.

@app.get("/sayi")
def sayi():
    return {"deger": 42}
# response body: {"deger":42}

If the function returns a BaseModel instance, FastAPI also turns it into structured data. This lets you shape API responses easily.

Exercise Define and test a GET route

Start with from fastapi import FastAPI and from fastapi.testclient import TestClient. Define app = FastAPI(). With @app.get("/merhaba") define def merhaba(): returning {"msg": "selam"}. Create a client with client = TestClient(app). Print the response body with print(client.get("/merhaba").text).

Show example solution

from fastapi import FastAPI
from fastapi.testclient import TestClient

app = FastAPI()

@app.get("/merhaba")
def merhaba():
    return {"msg": "selam"}

client = TestClient(app)
print(client.get("/merhaba").text)

Test yourself

Complete the get decorator

@____("/merhaba")
def merhaba():
    return {"msg": "selam"}

Show answer

@app.get("/merhaba")
def merhaba():
    return {"msg": "selam"}

What does the @app.get decorator do?
- Deletes a function
- Binds a function to a GET route
- Hides a function
- Calls a function twice
Show answer

Binds a function to a GET route — @app.get('/path') binds a function to a GET route.
Match the @app.get concepts

@app.get

Defines a GET route
/merhaba

Is the path string
def merhaba

Is the function definition
return {...}

Is the response body

Next lesson: Pydantic model

We Are Enhancing Your Experience

Cookie Preferences

Strictly Necessary Cookies

Analytical Cookies