forked from Ponysearch/Ponysearch
86 lines
2.2 KiB
Python
86 lines
2.2 KiB
Python
# WolframAlpha (Maths)
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#
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# @website http://www.wolframalpha.com/
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# @provide-api yes (http://api.wolframalpha.com/v2/)
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#
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# @using-api no
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# @results HTML
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# @stable no
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# @parse answer
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from re import search, sub
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from json import loads
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from urllib import urlencode
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from lxml import html
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import HTMLParser
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# search-url
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url = 'http://www.wolframalpha.com/'
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search_url = url + 'input/?{query}'
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# xpath variables
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scripts_xpath = '//script'
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title_xpath = '//title'
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failure_xpath = '//p[attribute::class="pfail"]'
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# do search-request
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def request(query, params):
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params['url'] = search_url.format(query=urlencode({'i': query}))
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return params
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# get response from search-request
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def response(resp):
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results = []
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line = None
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dom = html.fromstring(resp.text)
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scripts = dom.xpath(scripts_xpath)
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# the answer is inside a js function
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# answer can be located in different 'pods', although by default it should be in pod_0200
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possible_locations = ['pod_0200\.push\((.*)',
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'pod_0100\.push\((.*)']
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# failed result
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if dom.xpath(failure_xpath):
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return results
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# get line that matches the pattern
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for pattern in possible_locations:
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for script in scripts:
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try:
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line = search(pattern, script.text_content()).group(1)
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break
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except AttributeError:
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continue
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if line:
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break
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if line:
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# extract answer from json
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answer = line[line.find('{'):line.rfind('}') + 1]
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try:
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answer = loads(answer)
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except Exception:
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answer = loads(answer.encode('unicode-escape'))
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answer = answer['stringified']
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# clean plaintext answer
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h = HTMLParser.HTMLParser()
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answer = h.unescape(answer.decode('unicode-escape'))
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answer = sub(r'\\', '', answer)
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results.append({'answer': answer})
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# user input is in first part of title
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title = dom.xpath(title_xpath)[0].text.encode('utf-8')
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result_url = request(title[:-16], {})['url']
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# append result
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results.append({'url': result_url,
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'title': title.decode('utf-8')})
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return results
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