[wip] Create trivia quiz bot.

zulip_bots/zulip_bots/bots/trivia_quiz/requirements.txt

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+requests

zulip_bots/zulip_bots/bots/trivia_quiz/trivia_quiz.py

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+import html
+import json
+import requests
+import random
+import re
+from zulip_bots.lib import Any
+
+from typing import Optional, Any, Dict
+
+class NotAvailableException(Exception):
+    pass
+
+class InvalidAnswerException(Exception):
+    pass
+
+class TriviaQuizHandler:
+    def usage(self) -> str:
+        return '''
+            This plugin will give users a trivia question from
+            the open trivia database at opentdb.com.'''
+
+    def handle_message(self, message: Dict[str, Any], bot_handler: Any) -> None:
+        query = message['content']
+        if query == 'new':
+            try:
+                start_new_quiz(message, bot_handler)
+                return
+            except NotAvailableException:
+                bot_response = 'Uh-Oh! Trivia service is down.'
+                bot_handler.send_reply(message, bot_response)
+                return
+        elif query.startswith('answer'):
+            try:
+                (quiz_id, answer) = parse_answer(query)
+            except InvalidAnswerException:
+                bot_response = 'Invalid answer format'
+                bot_handler.send_reply(message, bot_response)
+                return
+            try:
+                quiz_payload = bot_handler.storage.get(quiz_id)
+            except KeyError:
+                bot_response = 'Invalid quiz id'
+                bot_handler.send_reply(message, bot_response)
+                return
+            quiz = json.loads(quiz_payload)
+            correct, bot_response = grade_question(quiz, answer)
+            bot_handler.send_reply(message, bot_response)
+            if correct:
+                start_new_quiz(message, bot_handler)
+            return
+        else:
+            bot_response = 'type "new" for a new question'
+        bot_handler.send_reply(message, bot_response)
+
+def start_new_quiz(message: Dict[str, Any], bot_handler: Any) -> None:
+    quiz = get_trivia_quiz()
+    quiz_id = generate_quiz_id(bot_handler.storage)
+    bot_response = format_quiz_for_markdown(quiz_id, quiz)
+    widget_content = format_quiz_for_widget(quiz_id, quiz)
+    bot_handler.storage.put(quiz_id, json.dumps(quiz))
+    bot_handler.send_reply(message, bot_response, widget_content)
+
+def parse_answer(query):
+    m = re.match('answer\s+(Q...)\s+(.)', query)
+    if not m:
+        raise InvalidAnswerException()
+
+    quiz_id = m.group(1)
+    answer = m.group(2).upper()
+    if answer not in 'ABCD':
+        raise InvalidAnswerException()
+
+    return (quiz_id, answer)
+
+def get_trivia_quiz() -> str:
+    payload = get_trivia_payload()
+    quiz = get_quiz_from_payload(payload)
+    return quiz
+
+def get_trivia_payload() -> str:
+
+    url = 'https://opentdb.com/api.php?amount=1&type=multiple'
+
+    try:
+        data = requests.get(url)
+
+    except requests.exceptions.RequestException:
+        raise NotAvailableException()
+
+    if data.status_code != 200:
+        raise NotAvailableException()
+
+    payload = data.json()
+    return payload
+
+def fix_quotes(s):
+    # opentdb is nice enough to escape HTML for us, but
+    # we are sending this to code that does that already :)
+    #
+    # Meanwhile Python took until version 3.4 to have a
+    # simple html.unescape function.
+    try:
+        return html.unescape(s)
+    except Exception:
+        raise Exception('Please use python3.4 or later for this bot.')
+
+def get_quiz_from_payload(payload):
+    result = payload['results'][0]
+    question = result['question']
+    letters = ['A', 'B', 'C', 'D']
+    random.shuffle(letters)
+    correct_letter = letters[0]
+    answers = dict()
+    answers[correct_letter] = result['correct_answer']
+    for i in range(3):
+        answers[letters[i+1]] = result['incorrect_answers'][i]
+    answers = {
+        letter: fix_quotes(answer)
+        for letter, answer
+        in answers.items()
+    }
+    quiz = dict(
+        question=fix_quotes(question),
+        answers=answers,
+        correct_letter=correct_letter,
+    )
+    return quiz
+
+def generate_quiz_id(storage) -> str:
+    try:
+        quiz_num = storage.get('quiz_id')
+    except KeyError:
+        quiz_num = 0
+    quiz_num += 1
+    quiz_num = quiz_num % (1000)
+    storage.put('quiz_id', quiz_num)
+    quiz_id = 'Q%03d' % (quiz_num,)
+    return quiz_id
+
+def format_quiz_for_widget(quiz_id, quiz):
+    widget_type = 'zform'
+    question = quiz['question']
+    answers = quiz['answers']
+
+    heading = quiz_id + ': ' + question
+
+    def get_choice(letter):
+        answer = answers[letter]
+        reply = 'answer ' + quiz_id + ' ' + letter
+
+        return dict(
+            type='multiple_choice',
+            short_name=letter,
+            long_name=answer,
+            reply=reply,
+        )
+
+    choices = [get_choice(letter) for letter in 'ABCD']
+
+    extra_data = dict(
+        type='choices',
+        heading=heading,
+        choices=choices,
+    )
+
+    widget_content = dict(
+        widget_type=widget_type,
+        extra_data=extra_data,
+    )
+    payload = json.dumps(widget_content)
+    return payload
+
+def format_quiz_for_markdown(quiz_id, quiz):
+    question = quiz['question']
+    answers = quiz['answers']
+    answer_list = '\n'.join([
+        '* **{letter}** {answer}'.format(
+            letter=letter,
+            answer=answers[letter],
+        )
+        for letter in 'ABCD'
+    ])
+    how_to_respond = '''**reply**: answer {quiz_id} <letter>'''.format(quiz_id=quiz_id)
+
+    content = '''
+Q: {question}
+
+{answer_list}
+{how_to_respond}'''.format(
+        question=question,
+        answer_list=answer_list,
+        how_to_respond=how_to_respond,
+    )
+    return content
+
+def grade_question(quiz, answer):
+    correct = (answer == quiz['correct_letter'])
+
+    if correct:
+        long_answer = quiz['answers'][answer]
+        response = '**CORRECT!** {long_answer} :tada:'.format(long_answer=long_answer)
+        return correct, response
+
+    response = '**WRONG!** {answer} is not correct :disappointed:'.format(answer=answer)
+    return correct, response
+
+
+handler_class = TriviaQuizHandler