bots: Move contrib_bots to api/bots*.

This will make it convenient to include these bots in Zulip API
releases on pypi.

Fix #5009.

bots/define/define.py

@@ -0,0 +1,66 @@
+# See readme.md for instructions on running this code.
+import logging
+import json
+import requests
+import html2text
+
+class DefineHandler(object):
+    '''
+    This plugin define a word that the user inputs. It
+    looks for messages starting with '@mention-bot'.
+    '''
+
+    DEFINITION_API_URL = 'https://owlbot.info/api/v1/dictionary/{}?format=json'
+    REQUEST_ERROR_MESSAGE = 'Definition not available.'
+    EMPTY_WORD_REQUEST_ERROR_MESSAGE = 'Please enter a word to define.'
+    PHRASE_ERROR_MESSAGE = 'Definitions for phrases are not available.'
+
+    def usage(self):
+        return '''
+            This plugin will allow users to define a word. Users should preface
+            messages with @mention-bot.
+            '''
+
+    def handle_message(self, message, client, state_handler):
+        original_content = message['content'].strip()
+        bot_response = self.get_bot_define_response(original_content)
+
+        client.send_reply(message, bot_response)
+
+    def get_bot_define_response(self, original_content):
+        split_content = original_content.split(' ')
+        # If there are more than one word (a phrase)
+        if len(split_content) > 1:
+            return DefineHandler.PHRASE_ERROR_MESSAGE
+
+        to_define = split_content[0].strip()
+        to_define_lower = to_define.lower()
+
+        # No word was entered.
+        if not to_define_lower:
+            return self.EMPTY_WORD_REQUEST_ERROR_MESSAGE
+        else:
+            response = '**{}**:\n'.format(to_define)
+
+            try:
+                # Use OwlBot API to fetch definition.
+                api_result = requests.get(self.DEFINITION_API_URL.format(to_define_lower))
+                # Convert API result from string to JSON format.
+                definitions = api_result.json()
+
+                # Could not fetch definitions for the given word.
+                if not definitions:
+                    response += self.REQUEST_ERROR_MESSAGE
+                else:  # Definitions available.
+                    # Show definitions line by line.
+                    for d in definitions:
+                        example = d['example'] if d['example'] else '*No example available.*'
+                        response += '\n' + '* (**{}**) {}\n  {}'.format(d['type'], d['defenition'], html2text.html2text(example))
+
+            except Exception as e:
+                response += self.REQUEST_ERROR_MESSAGE
+                logging.exception(e)
+
+            return response
+
+handler_class = DefineHandler

bots/define/readme.md

@@ -0,0 +1,21 @@
+# DefineBot
+
+* This is a bot that defines a word that the user inputs. Whenever the user
+inputs a message starting with '@define', the bot defines the word
+that follows.
+
+* The definitions are brought to the website using an API. The bot posts the
+definition of the word to the stream from which the user inputs the message.
+If the user inputs a word that does not exist or a word that is incorrect or
+is not in the dictionary, the definition is not displayed.
+
+* For example, if the user says "@define crash", all the meanings of crash
+appear, each in a separate line.
+
+![Correct Word](assets/correct_word.png)
+
+* If the user enters a wrong word, like "@define cresh" or "@define crish",
+then an error message saying no definition is available is displayed.
+
+![Wrong Word](assets/wrong_word.png)
+

bots/define/test_define.py

@@ -0,0 +1,28 @@
+#!/usr/bin/env python
+
+from __future__ import absolute_import
+from __future__ import print_function
+
+import os
+import sys
+
+our_dir = os.path.dirname(os.path.abspath(__file__))
+sys.path.insert(0, os.path.normpath(os.path.join(our_dir)))
+# For dev setups, we can find the API in the repo itself.
+if os.path.exists(os.path.join(our_dir, '..')):
+    sys.path.insert(0, '..')
+from bots_test_lib import BotTestCase
+
+class TestDefineBot(BotTestCase):
+    bot_name = "define"
+
+    def test_bot(self):
+        expected = {
+            "": 'Please enter a word to define.',
+            "foo": "**foo**:\nDefinition not available.",
+            "cat": ("**cat**:\n\n* (**noun**) a small domesticated carnivorous mammal "
+                    "with soft fur, a short snout, and retractile claws. It is widely "
+                    "kept as a pet or for catching mice, and many breeds have been "
+                    "developed.\n  their pet cat\n\n"),
+        }
+        self.check_expected_responses(expected)