[add] arxiv engine

searx/engines/arxiv.py

@@ -0,0 +1,73 @@
+#!/usr/bin/env python
+
+"""
+ ArXiV (Scientific preprints)
+ @website     https://axiv.org
+ @provide-api yes (export.arxiv.org/api/query)
+ @using-api   yes
+ @results     XML-RSS
+ @stable      yes
+ @parse       url, title, publishedDate, content
+ More info on api: https://arxiv.org/help/api/user-manual
+"""
+
+from lxml import html
+from datetime import datetime
+from searx.url_utils import urlencode
+
+
+categories = ['science']
+
+base_url = 'http://export.arxiv.org/api/query?search_query=all:'\
+           + '{query}&start={offset}&max_results={number_of_results}'
+
+# engine dependent config
+number_of_results = 10
+
+
+def request(query, params):
+    # basic search
+    offset = (params['pageno'] - 1) * number_of_results
+
+    string_args = dict(query=query,
+                       offset=offset,
+                       number_of_results=number_of_results)
+
+    params['url'] = base_url.format(**string_args)
+
+    return params
+
+
+def response(resp):
+    results = []
+
+    search_results = html.fromstring(resp.text.encode('utf-8')).xpath('//entry')
+
+    for entry in search_results:
+        title = entry.xpath('.//title')[0].text
+
+        url = entry.xpath('.//id')[0].text
+
+        content = entry.xpath('.//summary')[0].text
+
+        #  If a doi is available, add it to the snipppet
+        try:
+            doi = entry.xpath('.//link[@title="doi"]')[0].text
+            content = 'DOI: ' + doi + ' Abstract: ' + content
+        except:
+            pass
+
+        if len(content) > 300:
+                    content = content[0:300] + "..."
+        # TODO: center snippet on query term
+
+        publishedDate = datetime.strptime(entry.xpath('.//published')[0].text, '%Y-%m-%dT%H:%M:%SZ')
+
+        res_dict = {'url': url,
+                    'title': title,
+                    'publishedDate': publishedDate,
+                    'content': content}
+
+        results.append(res_dict)
+
+    return results