Fix linkbot title bug

If an HTML title was parsed with whitespace, it would not strip that
surrounding whitespace. This fixes that.

Also, there are some new debug log messages in linkbot. Hooray!

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

plugins/linkbot.py

@@ -22,7 +22,17 @@ class TitleParser(HTMLParser):
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         self.parsing_title = False
-        self.parsed_title: str | None = None
+        self.__parsed_title: str | None = None
+
+    @property
+    def parsed_title(self) -> str | None:
+        return self.__parsed_title
+
+    @parsed_title.setter
+    def parsed_title(self, value: str | None):
+        if value:
+            value = value.strip()
+        self.__parsed_title = value
 
     def reset(self) -> None:
         super().reset()
@@ -107,7 +117,10 @@ class Linkbot(Plugin):
         return False
 
     async def fetch(self, url: str) -> Tuple[int, str, str] | None:
-        async with aiohttp.ClientSession() as session:
+        headers = {
+            "User-Agent": "Omnibot",
+        }
+        async with aiohttp.ClientSession(headers=headers) as session:
             async with session.get(url) as response:
                 status = response.status
                 content_type = response.headers["content-type"].lower()
@@ -124,12 +137,14 @@ class Linkbot(Plugin):
         if not matches:
             return
         for url in matches:
+            log.debug("trying URL %s", url)
             if await self.is_blocked(url):
                 # Skip this URL if it's blocked
                 log.debug("skipping URL %s because it is blocked", url)
                 continue
             # Fetch the HTML at the URL
             result = await self.fetch(url)
+            log.debug("got %s characters back", len(result))
             if not result:
                 # Could not fetch this URL
                 log.debug("skipping URL %s because it couldn't be fetched", url)
@@ -142,6 +157,7 @@ class Linkbot(Plugin):
             if not (200 <= status <= 299):
                 message = f"{who.nick}: (status {status})"
             else:
+                log.debug("got title %r", title_parser.parsed_title)
                 message = title_parser.parsed_title
 
             if message: