[enh] add mongodb offline engine

# SPDX-License-Identifier: AGPL-3.0-or-later

"""

 MongoDB engine (Offline)

"""

# pylint: disable=missing-function-docstring

# pylint: disable=import-error

import re

from pymongo import MongoClient

engine_type = 'offline'

paging = True

# mongodb connection variables

host = '127.0.0.1'

port = 27017

username = ''

password = ''

database = None

collection = None

key = None

# engine specific variables

results_per_page = 20

exact_match_only = False

result_template = 'key-value.html'

_client = None

def init(_):

    connect()

def connect():

    global _client

    kwargs = {

        'port': port,

    }

    if username:

        kwargs['username'] = username

    if password:

        kwargs['password'] = password

    _client = MongoClient(host, **kwargs)[database][collection]

def search(query, params):

    ret = []

    if exact_match_only:

        q = {'$eq': query}

    else:

        q = {'$regex': re.compile('.*{0}.*'.format(re.escape(query)), re.I | re.M)}

    results = _client.find({key: q})\

                     .skip((params['pageno']-1)*results_per_page)\

                     .limit(results_per_page)

    ret.append({'number_of_results': results.count()})

    for r in results:

        del(r['_id'])

        r = {str(k):str(v) for k,v in r.items()}

        r['template'] = result_template

        ret.append(r)

    return ret

    engine : mixcloud

    shortcut : mc

# MongoDB engine

# Required dependency: pymongo

#  - name : mymongo

#    engine : mongodb

#    shortcut : md

#    exact_match_only : False

#    host : '127.0.0.1'

#    port : 27017

#    results_per_page : 20

#    database : 'business'

#    collection : 'reviews' # name of the db collection

#    key : 'name' # key in the collection to search for

  - name : npm

    engine : json_engine

    paging : True