Exception handling in routes in Flask - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the Flask class.

Flask

from flask import [1]

Drag options to blanks, or click blank then click option'

Arequest

BFlask

Crender_template

Djsonify

Attempts:

3 left

💡 Hint

Common Mistakes

Importing request instead of Flask

Using jsonify which is for JSON responses

Importing render_template which is for HTML templates

The Flask class is imported from the flask module to create the app instance.

2fill in blank

medium

Complete the code to define a route that handles GET requests at '/' path.

Flask

@app.route('[1]', methods=['GET'])
def home():
    return 'Hello World!'

Drag options to blanks, or click blank then click option'

A/

B/home

C/index

D/main

Attempts:

3 left

💡 Hint

Common Mistakes

Using '/home' or '/index' which are valid but not root

Forgetting the leading slash

The root path '/' is used to define the main page route.

3fill in blank

hard

Fix the error in the code to catch exceptions in the route.

Flask

from flask import Flask
app = Flask(__name__)

@app.route('/data')
def data():
    try:
        result = 10 / [1]
        return str(result)
    except ZeroDivisionError:
        return 'Cannot divide by zero', 400

Drag options to blanks, or click blank then click option'

A''

B0

CNone

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Using 0 causes a ZeroDivisionError

Using None or empty string causes TypeError

Dividing by 5 is valid and won't raise an exception. Dividing by 0 causes ZeroDivisionError.

4fill in blank

hard

Fill both blanks to raise and catch a ValueError in the route.

Flask

@app.route('/check')
def check():
    try:
        if int('abc') [1] ValueError:
            raise ValueError('Invalid number')
    except [2] as e:
        return str(e), 400

Drag options to blanks, or click blank then click option'

A==

B!=

CValueError

DTypeError

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' instead of '!=' in condition

Catching wrong exception type like TypeError

The code checks if conversion raises ValueError and catches it properly.

5fill in blank

hard

Fill all three blanks to handle a KeyError in a route and return JSON error message.

Flask

from flask import jsonify

@app.route('/item')
def item():
    data = {'name': 'apple'}
    try:
        value = data[[1]]
        return jsonify({{'value': value}})
    except [2] as e:
        return jsonify({{'error': str(e)}}), [3]

Drag options to blanks, or click blank then click option'

A'price'

BKeyError

C404

D'name'

Attempts:

3 left

💡 Hint

Common Mistakes

Using existing key 'name' so no error occurs

Catching wrong exception type

Returning wrong status code

Accessing missing key 'price' raises KeyError, caught and returns 404 with JSON error.