Essential Books

Routing URLs

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With Flask, URL routing is traditionally done using decorators. These decorators can be used for static routing, as well as routing URLs with parameters. For the following example, imagine this Flask script is running the website www.example.com. 

@app.route("/")
def index():
    return "You went to www.example.com"

@app.route("/about")
def about():
    return "You went to www.example.com/about"

@app.route("/users/guido-van-rossum")
    return "You went to www.example.com/guido-van-rossum"

With that last route, you can see that given a URL with /users/ and the profile name, we could return a profile. Since it would be horribly inefficient and messy to include a @app.route() for every user, Flask offers to take parameters from the URL: 

@app.route("/users/<username>")
def profile(username):
    return "Welcome to the profile of " + username

cities = ["OMAHA", "MELBOURNE", "NEPAL", "STUTTGART", "LIMA", "CAIRO", "SHANGHAI"]

@app.route("/stores/locations/<city>")
def storefronts(city):
    if city in cities:
        return "Yes! We are located in " + city
    else:
        return "No. We are not located in " + city
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Flask:
* Flask
* Files and Templates
* The basics
* Routing URLs
* HTTP Methods
* Jinja Templating
* The Request Object
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