Respecting API rate limits

Let's put what we learned about error handling to the test. In this exercise you'll encounter a rate-limit error, which means you're sending too many requests to the server in a short amount of time. Let's fix it by implementing a workaround to circumvent the rate limit so our script doesn't fail.

Your music library contains over 3500 music tracks, so let's try to find the longest track by checking the Length property of each track.

But there is an issue, the /tracks API has a maximum page size of 500 items and has a rate-limit of 1 request per second. The script we've written is sending too many requests to the server in a short amount of time. Let's fix it!

The requests and time packages are already imported, and we've created the following variables for you:

longestTrackLength = 0
longestTrackTitle = ""
headers = {'Authorization': 'Bearer 8apDFHaNJMxy8Kt818aa6b4a0ed0514b5d3'}
page_number = 1

This exercise is part of the course

Introduction to APIs in Python

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Exercise instructions

Start by running the exercise without making changes to the code, you'll notice that the console outputs a 429 Client Error indicating we are sending too many requests to the server in a short amount of time.
Fix the script by adding a 3 second pause at the end of the while-loop using the sleep method from the time package.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

while True:
    params = {'page': page_number, 'per_page': 500}
    response = requests.get('http://localhost:3000/tracks', params=params, headers=headers)
    response.raise_for_status()
    response_data = response.json()
    
    print(f'Fetching tracks page {page_number}')

    if len(response_data['results']) == 0:
        break

    for track in response_data['results']:
        if(track['Length'] > longestTrackLength):
            longestTrackLength = track['Length']
            longestTrackTitle = track['Name']

    page_number = page_number + 1
    
    # Add your fix here
    ____.____(3)

print('The longest track in my music library is: ' + longestTrackTitle)

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