Include redirect to URL in notification emails

Closes: #5

check.py

@@ -121,7 +121,9 @@ def normalize_url(url: str) -> str:
     return urlunparse(parsed_url._replace(netloc=normalized_netloc))
 
 
-def check_conference(name: str, src_url: str, year: int) -> tuple[bool, str]:
+def check_conference(
+    name: str, src_url: str, year: int
+) -> tuple[bool, str, str | None]:
     """Check if conference is live."""
     url = src_url.format(year=year)
     past_url = src_url.format(year=year - 1)
@@ -129,7 +131,7 @@ def check_conference(name: str, src_url: str, year: int) -> tuple[bool, str]:
         # SotM Baltics has an invalid TLS certificate, but we don't care
         r = s.get(url, verify=False)
     except requests.exceptions.ConnectionError:
-        return (False, "connection refused")
+        return (False, "connection refused", None)
 
     not_here = find_not_here_message(r.text)
     if (
@@ -137,15 +139,12 @@ def check_conference(name: str, src_url: str, year: int) -> tuple[bool, str]:
         and 'http-equiv="refresh"' in r.text
         and str(year) not in r.text
     ):
-        return (False, "redirect to URL without year")
-
-    if str(year) not in r.url:
-        return (False, "redirect to URL without year")
+        return (False, "redirect to URL without year", r.url)
 
     if normalize_url(r.url) == normalize_url(past_url):
-        return (False, "redirect to previous year")
+        return (False, "redirect to previous year", r.url)
 
-    return (False, not_here) if not_here else (True, get_title(r.text))
+    return (False, not_here, r.url) if not_here else (True, get_title(r.text), r.url)
 
 
 def send_mail(subject: str, body: str) -> None:
@@ -174,10 +173,15 @@ def send_mail(subject: str, body: str) -> None:
 def check_conference_web_site(name: str, src_url: str, year: int) -> bool:
     """Check if an individual web site is live."""
     assert "{year}" in src_url
-    live, msg = check_conference(name, src_url, year)
+    live, msg, redirect_to_url = check_conference(name, src_url, year)
     url = src_url.format(year=year)
     if live:
-        body = f"{name}\n{url}\nWeb page title: {msg}"
+        if redirect_to_url == url:
+            body = f"{name}\n{url}\nWeb page title: {msg}"
+        else:
+            body = f"""{name}
+{url} redirects to {redirect_to_url}
+Web page title: {msg}"""
         send_mail(f"Conference site live: {name} - {year}", body)
 
     return live