mathematicians.py

from requests import get
from requests.exceptions import RequestException
from contextlib import closing
from bs4 import BeautifulSoup


def simple_get(url):
    """
    Attempts to get the content at `url` by making an HTTP GET request.
    If the content-type of response is some kind of HTML/XML, return the
    text content, otherwise return None
    """
    try:
        with closing(get(url, stream=True)) as resp:
            if is_good_response(resp):
                return resp.content
            else:
                return None

    except RequestException as e:
        log_error("Error during requests to {0} : {1}".format(url, str(e)))
        return None


def is_good_response(resp):
    """
    Returns true if the response seems to be HTML, false otherwise
    """
    content_type = resp.headers["Content-Type"].lower()
    return (
        resp.status_code == 200
        and content_type is not None
        and content_type.find("html") > -1
    )


def log_error(e):
    """
    It is always a good idea to log errors.
    This function just prints them, but you can
    make it do anything.
    """
    print(e)


def get_names():
    """
    Downloads the page where the list of mathematicians is found
    and returns a list of strings, one per mathematician
    """
    url = "http://www.fabpedigree.com/james/mathmen.htm"
    response = simple_get(url)

    if response is not None:
        html = BeautifulSoup(response, "html.parser")
        names = set()
        for li in html.select("li"):
            for name in li.text.split("\n"):
                if len(name) > 0:
                    names.add(name.strip())

        return list(names)

    # Raise an exception if we failed to get any data from the url
    raise Exception("Error retrieving contents at {}".format(url))


def get_hits_on_name(name):
    """
    Accepts a `name` of a mathematician and returns the number
    of hits that mathematician's wikipedia page received in the
    last 60 days, as an `int`
    """
    # url_root is a template string that used to buld a URL.
    url_root = "https://xtools.wmflabs.org/articleinfo/en.wikipedia.org/{}"
    response = simple_get(url_root.format(name))

    if response is not None:
        html = BeautifulSoup(response, "html.parser")

        hit_link = [a for a in html.select("a") if a["href"].find("latest-60") > -1]

        if len(hit_link) > 0:
            # Strip commas:
            link_text = hit_link[0].text.replace(",", "")
            try:
                # Convert to integer
                return int(link_text)
            except ValueError:
                log_error("couldn't parse {} as an `int`".format(link_text))

    log_error("No pageviews found for {}".format(name))

    return None


if __name__ == "__main__":
    print("Getting the list of names....")
    names = get_names()
    print("... done.\n")

    results = []

    print("Getting stats for each name....")

    for name in names:
        try:
            hits = get_hits_on_name(name)
            if hits is None:
                hits = -1
            results.append((hits, name))
        except Exception:
            results.append((-1, name))
            log_error("error encountered while processing " "{}, skipping".format(name))

    print("... done.\n")

    results.sort()
    results.reverse()

    if len(results) > 5:
        top_marks = results[:5]
    else:
        top_marks = results

    print("\nThe most popular mathematicians are:\n")
    for (mark, mathematician) in top_marks:
        print("{} with {} page views".format(mathematician, mark))

    no_results = len([res for res in results if res[0] == -1])
    print(
        "\nBut we did not find results for "
        "{} mathematicians on the list".format(no_results)
    )