urlinfo: check content-type before downloading + handle timeouts

improve codestyle and formatting

bot/urlinfo.py

@@ -16,6 +16,7 @@ class URLInfo(Plugin):
         "^https?:\/\/(?:(?:vid|img|thumb)\.)?pr0gramm\.com"
     ]
 
+    # set the size limit to 2 MB so we don't fully download too large resources
     SIZE_LIMIT = 2 * 1024 ** 2
 
     @irc3.event(r'(?i)^:\S+ PRIVMSG (?P<target>\S+) :.*(?P<url>https?:\/\/\S+\.\S+).*')
@@ -23,26 +24,27 @@ class URLInfo(Plugin):
         for regex in self.BLACKLIST:
             if re.match(regex, url):
                 return
+
         bytes_io = io.BytesIO()
+
         try:
             with requests.get(url, timeout=10, stream=True) as r:
                 r.raise_for_status()
+                mime_type = r.headers.get("content-type")
+                if mime_type is not None and mime_type.split(";")[0] != "text/html":
+                    return
                 size = 0
                 for chunk in r.iter_content(chunk_size=1024 ** 2):
                     size += len(chunk)
                     if size >= self.SIZE_LIMIT:
                         return
                     bytes_io.write(chunk)
-        except (requests.exceptions.ConnectionError, requests.exceptions.HTTPError) as e:
+        except (requests.exceptions.ConnectionError, requests.exceptions.HTTPError, requests.exceptions.ReadTimeout):
             return
 
-        mime_type = r.headers.get("content-type")
-        if mime_type is not None:
-            if mime_type.split(";")[0] != "text/html":
-                return
         bytes_io.seek(0)
         tree = etree.parse(bytes_io, etree.HTMLParser()).getroot()
-        title = tree.xpath("/html/head/title")
-        if len(title) > 0:
-            self.bot.privmsg(target, '\x02[URLInfo]\x02 ' + title[0].text.strip())
+        title_elements = tree.xpath("/html/head/title")
+        if len(title_elements) > 0:
+            self.bot.privmsg(target, '\x02[URLInfo]\x02 ' + title_elements[0].text.strip())