stackoverflow_plc.py

import logging
import matplotlib.pyplot as plt
import numpy as np
import pandas as pd
import requests

from collections import defaultdict
from datetime import timedelta, datetime
from glob import glob
import matplotlib.dates as mdates


def all_tags(path):
    return [tag.split(".")[-2] for tag in glob(path)]


def cumulative_entries(dataframe):
    return (~dataframe.sort_index().duplicated()).cumsum().values


def get_latest_questions(tag: str) -> str:
    """Get the last 30 questions for a certain tag"""
    STACKEXCHANGE_API_URL = "https://api.stackexchange.com/2.3/search"
    payload = {
        "sort": "creation",
        "order": "desc",
        "site": "stackoverflow",
        "tagged": tag,
    }
    r = requests.get(STACKEXCHANGE_API_URL, params=payload)

    if not r.ok:
        logging.error(
            f"Failed to get latest questions for {tag}. Error code {r.status_code}: {r.reason}"
        )

    return r.json()


def get_question_id_and_date(questions) -> pd.DataFrame:
    """Return question ID and creation date from questions in json"""
    new_questions = defaultdict(list)
    for item in questions["items"]:
        new_questions["Post Link"].append(item["question_id"])
        date = pd.to_datetime(item["creation_date"], unit="s")
        new_questions["Creation Date"].append(date)

    new_questions = pd.DataFrame.from_dict(new_questions)
    new_questions.set_index("Post Link", inplace=True)

    return new_questions


def get_questions_from_csv(fname):
    return pd.read_csv(fname, index_col=0, parse_dates=["Creation Date"])


so_tag_style = dict(
    color="#797ca0",
    bbox=dict(
        boxstyle="round",
        ec=("#e1ecf4"),
        fc=("#e1ecf4"),
    ),
)


def plotAndSaveStackOverflowQuestions():
    plt.figure(figsize=(9, 5))
    ax = plt.subplot(111)

    for tag in all_tags("*.csv"):
        latest_questions = get_question_id_and_date(get_latest_questions(tag))
        fname = f"{tag}.csv"
        old_questions = get_questions_from_csv(fname)
        old_and_new = old_questions.combine_first(latest_questions)
        old_and_new["Cumulative questions"] = cumulative_entries(old_and_new)
        old_and_new.to_csv(fname)

        t = old_and_new["Creation Date"]
        y = old_and_new["Cumulative questions"]
        plt.semilogy(t, y)
        plt.text(
            t.iat[-1] + timedelta(days=150),
            y.iat[-1],
            f"{tag}: {y.iat[-1]}",
            **so_tag_style,
        )

    plt.annotate(
        f"Last updated: {datetime.today():%d %B %Y}",
        xy=(0.03, 0.95),
        xycoords="axes fraction",
        ha="left",
        color="gray",
    )
    plt.xlabel("Year")
    plt.title(
        "Number of StackOverflow questions for PLC related tags",
        pad=20,
    )

    # Hide the right and top spines
    ax.spines["right"].set_visible(False)
    ax.spines["top"].set_visible(False)

    plt.tight_layout()
    plt.savefig("questions.png")


def plotAndSaveSupportTickets():
    tickets = pd.read_csv("support-ch.txt", index_col=1, parse_dates=True)
    tickets.sort_index(inplace=True)

    fig, ax = plt.subplots(figsize=(9, 5))

    plt.scatter(tickets.index, tickets["Id"])

    # Hide the right and top spines
    ax.spines["right"].set_visible(False)
    ax.spines["top"].set_visible(False)

    plt.title("Beckhoff support Switzerland ticket numbers")
    plt.ylabel("Ticket ID")
    plt.xlabel("Date")

    # Change x-axis ticks to 6 month period
    fmt_half_year = mdates.MonthLocator(interval=6)
    ax.xaxis.set_major_locator(fmt_half_year)

    plt.tight_layout()
    plt.savefig("support.png")


if __name__ == "__main__":
    plt.rcParams.update({"font.size": 12})
    plotAndSaveStackOverflowQuestions()
    plotAndSaveSupportTickets()