[Cache] Add some more debugging and error logging

src/cache.rs

@@ -273,7 +273,10 @@ impl UserInfo {
         // Determine XDG directories now
         let base_dirs = match BaseDirectories::with_prefix(BASE_NAME) {
             Ok(b) => b,
-            Err(e) => return Err(io::Error::new(io::ErrorKind::Other, e))
+            Err(e) => {
+                error!("Could not determine XDG base directories: {}", e);
+                return Err(io::Error::new(io::ErrorKind::Other, e));
+            }
         };
 
         // Restore $HOME to original if we changed it earlier
@@ -292,7 +295,10 @@ impl UserInfo {
     fn place_user_cache_file(&mut self, filename: String) -> Result<PathBuf, io::Error> {
         match self.get_user_xdg_base_directories() {
             Ok(b) => b.place_cache_file(filename),
-            Err(e) => Err(e)
+            Err(e) => {
+                error!("Error placing cache file {}: {}", filename, e);
+                Err(e)
+            }
         }
     }
 
@@ -328,7 +334,7 @@ impl UserInfo {
     /// write the token to disk afterwards
     pub fn set_access_token(&mut self, token: BasicTokenResponse) -> Result<(), io::Error> {
         self.access_token = Some(token.clone());
-        debug!("Saved token for in memory");
+        debug!("Saved token in memory");
 
         // Try to write user's token cache file
         // We need to ensure privileges were dropped successfully to avoid symlink attacks
@@ -339,9 +345,15 @@ impl UserInfo {
                     debug!("Storing token for in cache file");
                     save_json(path, token)
                 },
-                Err(e) => Err(e)
+                Err(e) => {
+                    error!("Error getting cache path in user home: {}", e);
+                    Err(e)
+                }
             },
-            Err(e) => Err(e)
+            Err(e) => {
+                error!("Error dropping privileges to store token in user home: {}", e);
+                Err(e)
+            }
         };
         self.restore_privileges();
         return res;