Fix empty size in response and write debug file on HTTP error

grmn/updateserver.py

@@ -85,7 +85,10 @@ class UpdateInfo:
         for f in files:
             # For some reason, WebUpdater returns file size in KiB instead of Bytes
             size_kb = self.dom_get_text(f.getElementsByTagName("Size"))
-            size_bytes = float(size_kb) * 1024
+            if not size_kb.isdecimal():
+                size_bytes = None
+            else:
+                size_bytes = float(size_kb) * 1024
             self.files.append( {
                 "url": self.dom_get_text(f.getElementsByTagName("Location")),
                 "md5": self.dom_get_text(f.getElementsByTagName("MD5Sum")),
@@ -288,14 +291,14 @@ class UpdateServer:
 
         r = requests.post(WEBUPDATER_SOFTWAREUPDATE_URL, headers=headers, data=data)
 
-        if r.status_code != 200:
-            r.raise_for_status()
-            return None
-
         if self.debug:
             #print(r.content)
             with open("webupdaterreply.xml", "wb") as f:
                 f.write(r.content)
                 f.close()
 
+        if r.status_code != 200:
+            r.raise_for_status()
+            return None
+
         return r.content