Routing

Code

from flask import Flask, request

app = Flask(__name__)

@app.route("/")
def index():
    return "Hello, Flask!"

@app.route("/user/<username>")
def show_user(username):
    return f"User: {username}"

@app.route("/post/<int:post_id>")
def show_post(post_id):
    return f"Post #{post_id}"

@app.route("/api", methods=["GET", "POST"])
def api():
    if request.method == "POST":
        return "created", 201
    return "list"

if __name__ == "__main__":
    app.run(debug=True)

Explanation

The @app.route decorator maps a URL to a view function. Converters like <int:post_id> validate and cast URL segments, while the methods argument restricts accepted HTTP verbs. Returning a tuple like (body, status_code) sets the response status.

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