Leetcode API implementation

This repo contains a python client to access all known so far methods of Leetcode API.

The code is autogenerated by swagger. Swagger reference can be found here: https://github.com/prius/leetcode-swagger

PyPi package link: https://pypi.org/project/python-leetcode/

Minimal working example

First set up a virtualenv

virtualenv -p python3 leetcode
. leetcode/bin/activate
pip3 install python-leetcode

Then in python shell initialize the client (if you're using chrome, cookies can be found here chrome://settings/cookies/detail?site=leetcode.com)

import leetcode

# Get the next two values from your browser cookies
leetcode_session = "yyy"
csrf_token = "xxx"

# Experimental: Or CSRF token can be obtained automatically
import leetcode.auth
csrf_token = leetcode.auth.get_csrf_cookie(leetcode_session)

configuration = leetcode.Configuration()

configuration.api_key["x-csrftoken"] = csrf_token
configuration.api_key["csrftoken"] = csrf_token
configuration.api_key["LEETCODE_SESSION"] = leetcode_session
configuration.api_key["Referer"] = "https://leetcode.com"
configuration.debug = False

api_instance = leetcode.DefaultApi(leetcode.ApiClient(configuration))

Now once the client is initilized, you can start performing actual queries

graphql_request = leetcode.GraphqlQuery(
    query="""
      {
        user {
          username
          isCurrentUserPremium
        }
      }
    """,
    variables=leetcode.GraphqlQueryVariables(),
)

print(api_instance.graphql_post(body=graphql_request))

You should get something like that in the response

{'data': {'question': None,
          'user': {'is_current_user_premium': True, 'username': 'omgitspavel'}}}

This confirms you've set up auth correctly.

Advanced example

Now let's try to do something more complicated. For example calculate the percentage of the problems we've solved by topic.

For that we have to acquire the list of all the problems we solved.

api_response = api_instance.api_problems_topic_get(topic="algorithms")

slug_to_solved_status = {
    pair.stat.question__title_slug: True if pair.status == "ac" else False
    for pair in api_response.stat_status_pairs
}

Now for each problem we want to get its tags

import time

from collections import Counter


topic_to_accepted = Counter()
topic_to_total = Counter()


# Take only the first 10 for test purposes
for slug in list(slug_to_solved_status.keys())[:10]:
    time.sleep(1)  # Leetcode has a rate limiter
    
    graphql_request = leetcode.GraphqlQuery(
        query="""
            query getQuestionDetail($titleSlug: String!) {
              question(titleSlug: $titleSlug) {
                topicTags {
                  name
                  slug
                }
              }
            }
        """,
        variables=leetcode.GraphqlQueryVariables(title_slug=slug),
        operation_name="getQuestionDetail",
    )

    api_response = api_instance.graphql_post(body=graphql_request)
    
    for topic in (tag.slug for tag in api_response.data.question.topic_tags):
        topic_to_accepted[topic] += int(slug_to_solved_status[slug])
        topic_to_total[topic] += 1

print(
    list(
        sorted(
            ((topic, accepted / topic_to_total[topic]) for topic, accepted in topic_to_accepted.items()),
            key=lambda x: x[1]
        )
    )
)

The output will look like this:

[('memoization', 0.0),
 ('number-theory', 0.0),
 ('binary-search-tree', 0.0),
 ('quickselect', 0.0),
 ('recursion', 0.0),
 ('suffix-array', 0.0),
 ('topological-sort', 0.0),
 ('shortest-path', 0.0),
 ('trie', 0.0),
 ('geometry', 0.0),
 ('brainteaser', 0.0),
 ('combinatorics', 0.0),
 ('line-sweep', 0.0),
 
 ...
 
 ('union-find', 0.3076923076923077),
 ('linked-list', 0.3333333333333333),
 ('string-matching', 0.3333333333333333),
 ('segment-tree', 0.4),
 ('data-stream', 0.5),
 ('strongly-connected-component', 0.5),
 ('minimum-spanning-tree', 0.6666666666666666),
 ('merge-sort', 1.0),
 ('doubly-linked-list', 1.0)]

So it is clearly visible which topics we should focus on in our preparation. In this case memoization topic is one of the targets for improvement, so I can go to https://leetcode.com/tag/memoization/ and choose a new memoization problem. Or use python to automate the process.

Example services using this library

• Anki cards generator https://github.com/prius/leetcode-anki
• Leetcode helper website https://github.com/prius/grind-helper

Additional info

You can find other examples of usage in example.py

Autogenerated by swagger documentation can be found here.