[enh] add blekko_images engine

## Blekko (Images)

#

# @website     https://blekko.com

# @provide-api yes (inofficial)

#

# @using-api   yes

# @results     JSON

# @stable      yes

# @parse       url, title, img_src

from json import loads

from urllib import urlencode

# engine dependent config

categories = ['images']

paging = True

# search-url

base_url = 'https://blekko.com'

search_url = '/api/images?{query}&c={c}'

# do search-request

def request(query, params):

    c = (params['pageno'] - 1) * 48

    params['url'] = base_url +\

        search_url.format(query=urlencode({'q': query}),

                          c=c)

    if params['pageno'] != 1:

        params['url'] += '&page={pageno}'.format(pageno=(params['pageno']-1))

    return params

# get response from search-request

def response(resp):

    results = []

    search_results = loads(resp.text)

    # return empty array if there are no results

    if not search_results:

        return []

    for result in search_results:

        # append result

        results.append({'url': result['page_url'],

                        'title': result['title'],

                        'content': '',

                        'img_src': result['url'],

                        'template': 'images.html'})

    # return results

    return results

    locale : en-US

    shortcut : bin

  - name : blekko images

    engine : blekko_images

    locale : en-US

    shortcut : bli

  - name : btdigg

    engine : btdigg

    shortcut : bt

from collections import defaultdict

import mock

from searx.engines import blekko_images

from searx.testing import SearxTestCase

class TestBlekkoImagesEngine(SearxTestCase):

    def test_request(self):

        query = 'test_query'

        dicto = defaultdict(dict)

        dicto['pageno'] = 0

        params = blekko_images.request(query, dicto)

        self.assertTrue('url' in params)

        self.assertTrue(query in params['url'])

        self.assertTrue('blekko.com' in params['url'])

    def test_response(self):

        self.assertRaises(AttributeError, blekko_images.response, None)

        self.assertRaises(AttributeError, blekko_images.response, [])

        self.assertRaises(AttributeError, blekko_images.response, '')

        self.assertRaises(AttributeError, blekko_images.response, '[]')

        response = mock.Mock(text='[]')

        self.assertEqual(blekko_images.response(response), [])

        json = """

        [

            {

                "c": 1,

                "page_url": "http://result_url.html",

                "title": "Photo title",

                "tn_url": "http://ts1.mm.bing.net/th?id=HN.608050619474382748&pid=15.1",

                "url": "http://result_image.jpg"

            },

            {

                "c": 2,

                "page_url": "http://companyorange.simpsite.nl/OSM",

                "title": "OSM",

                "tn_url": "http://ts2.mm.bing.net/th?id=HN.608048068264919461&pid=15.1",

                "url": "http://simpsite.nl/userdata2/58985/Home/OSM.bmp"

            },

            {

                "c": 3,

                "page_url": "http://invincible.webklik.nl/page/osm",

                "title": "OSM",

                "tn_url": "http://ts1.mm.bing.net/th?id=HN.608024514657649476&pid=15.1",

                "url": "http://www.webklik.nl/user_files/2009_09/65324/osm.gif"

            },

            {

                "c": 4,

                "page_url": "http://www.offshorenorway.no/event/companyDetail/id/12492",

                "title": "Go to OSM Offshore AS homepage",

                "tn_url": "http://ts2.mm.bing.net/th?id=HN.608054265899847285&pid=15.1",

                "url": "http://www.offshorenorway.no/firmalogo/OSM-logo.png"

            }

        ]

        """

        response = mock.Mock(text=json)

        results = blekko_images.response(response)

        self.assertEqual(type(results), list)

        self.assertEqual(len(results), 4)

        self.assertEqual(results[0]['title'], 'Photo title')

        self.assertEqual(results[0]['url'], 'http://result_url.html')

        self.assertEqual(results[0]['img_src'], 'http://result_image.jpg')

from searx.tests.engines.test_bing import *  # noqa

from searx.tests.engines.test_bing_images import *  # noqa

from searx.tests.engines.test_bing_news import *  # noqa

from searx.tests.engines.test_blekko_images import *  # noqa

from searx.tests.engines.test_btdigg import *  # noqa

from searx.tests.engines.test_dailymotion import *  # noqa

from searx.tests.engines.test_deezer import *  # noqa