search.py

#################################
# Programmer: Kenneth Sinder
# Date Created: 2017-02-10
# Filename: search.py
# Description: Main search script
#################################

import argparse
import os
from dbconnect import ConversationRetrievalService

DESCRIPTION = 'Skype conversation search tool'

class Searcher(object):
    """
    Skype message searcher.
    Implements `filter([str]) -> str`.
    """

    conversation_service = None
    messages = []
    ci = False

    def __init__(self, conversation_service, username, case_insensitive=False):
        """ (class, str, [bool]) -> Searcher
        Prepares a new Searcher object by constructing the given
        `conversation_service` class (which must implement `retrieve([bool])`
        to retrieve a list of chat message dicts, and take in a username
        in its constructor) and calling `retrieve` on the service instance
        to populate messages internally.
        """
        self.conversation_service = conversation_service(username)
        self.messages = self.conversation_service.retrieve(True)
        self.ci = case_insensitive

    def filter(self, string=''):
        """ ([str]) -> list of dict
        Returns a new list of chat messages only containing
        the given `string` in the message body. Default behaviour
        without `string` parameter is to return all messages unfiltered.
        """
        match_function = self._is_ci_match if self.ci else self._is_match
        return os.linesep.join([self._convert_message(m) \
                for m in self.messages if match_function(string, m)])

    def _is_match(self, string: str, msg: dict) -> bool:
        """ (str, dict) -> bool
        Returns True iff `s` is a substring of the message body
        within `msg`.
        """
        return string in msg['message']

    def _is_ci_match(self, string: str, msg: dict) -> bool:
        """ (str, dict) -> bool
        Returns true iff `s` is a case-insensitive substring of the
        message body within `msg`.
        """
        return string.upper() in msg['message'].upper()

    def _convert_message(self, message) -> str:
        """ (dict) -> str
        Convert a `message` represented as a dictionary to an appropriate
        string format for printing.
        """
        result = "From: {0} ({1})" + os.linesep + "Date: {2}" + \
                os.linesep + "Conversation ID: {3}" + os.linesep
        result += "Message:" + os.linesep + "{4}" + os.linesep
        result = result.format(message['display_name'], message['username'], \
                message['local_datetime'], \
                message['conversation_id'], \
                message['message'])
        return result

def main():
    """ () -> None
    Main program entry point.
    """
    # Deal with the two command-line arguments
    parser = argparse.ArgumentParser(description=DESCRIPTION)
    parser.add_argument('username', metavar='username', type=str,
                        help='Skype username')
    parser.add_argument('query', metavar='query', type=str, help='Search query')
    parser.add_argument('-c', '--case-insensitive', dest='case_insensitive', \
                        help='Do a case-sensitive search', default=False, action='store_true')
    args = parser.parse_args()

    # Create Searcher object
    searcher = Searcher(ConversationRetrievalService, args.username, args.case_insensitive)

    # Filter and print the result
    try:
        print(searcher.filter(args.query))
    except UnicodeEncodeError:
        print(r"You must set up Unicode in Command Prompt. Please see README.md for details.")

if __name__ == '__main__':
    main()