Fix error if puid doesn't exist

.gitignore

@@ -1,4 +1,5 @@
 package
 .idea
 .venv
-site/
+site/
+indexes

results.py

@@ -8,6 +8,14 @@
 )
 
 
+def puid_exists(puid):
+    conn = sqlite3.connect("indexes")
+    cursor = conn.cursor()
+    cursor.execute("SELECT path from indexes where path = ?", (puid,))
+    rows = cursor.fetchall()
+    return len(rows) > 0
+
+
 def search(search_string):
     conn = sqlite3.connect('indexes')
     cur = conn.cursor()
@@ -20,7 +28,7 @@ def search(search_string):
 def lambda_handler(event, _):
     query_params = event.get("queryStringParameters", {})
     search_term = query_params.get("q") if query_params else None
-    if re.search(r'^(x-)?fmt\/\d{1,5}$', search_term) is not None:
+    if re.search(r'^(x-)?fmt\/\d{1,5}$', search_term) is not None and puid_exists(search_term):
         return {
             "statusCode": 302,
             "headers": {'Location': f'{search_term}.html'}

templates/home.html

@@ -6,4 +6,6 @@ <h3 class="tna-heading-m">
   <a href="/search.html">Search PRONOM</a>
   <br>
   <a href="https://github.com/nationalarchives/pronom-signatures/">Contribute to PRONOM</a>
+  <br>
+  <a href="/signature_list.html">View signature files</a>
 </h3>