11341: Use NamedTemporaryFile instead of mkstemp for cache saving.

Added logging messages to inform the user what's happening with the cache file.

diff --git a/sdk/python/arvados/commands/put.py b/sdk/python/arvados/commands/put.py
index 32d5fef6a8588e1f2785517435949082dd5b3534..83fde9cba48b441ad1c1bf5a7e463430cf0a64df 100644 (file)
--- a/sdk/python/arvados/commands/put.py
+++ b/sdk/python/arvados/commands/put.py
@@ -543,7 +543,10 @@ class ArvPutUploadJob(object):
                     with self._state_lock:
                         self._state['manifest'] = manifest
             if self.use_cache:
-                self._save_state()
+                try:
+                    self._save_state()
+                except Exception as e:
+                    self.logger.error("Unexpected error trying to save cache file: {}".format(e))
         else:
             self.bytes_written = self.bytes_skipped
         # Call the reporter, if any
@@ -673,10 +676,12 @@ class ArvPutUploadJob(object):
             cache_filepath = os.path.join(
                 arv_cmd.make_home_conf_dir(self.CACHE_DIR, 0o700, 'raise'),
                 cache_filename)
-            if self.resume:
+            if self.resume and os.path.exists(cache_filepath):
+                self.logger.info("Resuming upload from cache file {}".format(cache_filepath))
                 self._cache_file = open(cache_filepath, 'a+')
             else:
                 # --no-resume means start with a empty cache file.
+                self.logger.info("Creating new cache file create at {}".format(cache_filepath))
                 self._cache_file = open(cache_filepath, 'w+')
             self._cache_filename = self._cache_file.name
             self._lock_file(self._cache_file)
@@ -719,20 +724,19 @@ class ArvPutUploadJob(object):
         """
         Atomically save current state into cache.
         """
+        with self._state_lock:
+            # We're not using copy.deepcopy() here because it's a lot slower
+            # than json.dumps(), and we're already needing JSON format to be
+            # saved on disk.
+            state = json.dumps(self._state)
         try:
-            with self._state_lock:
-                # We're not using copy.deepcopy() here because it's a lot slower
-                # than json.dumps(), and we're already needing JSON format to be
-                # saved on disk.
-                state = json.dumps(self._state)
-            new_cache_fd, new_cache_name = tempfile.mkstemp(
-                dir=os.path.dirname(self._cache_filename))
-            self._lock_file(new_cache_fd)
-            new_cache = os.fdopen(new_cache_fd, 'r+')
+            new_cache = tempfile.NamedTemporaryFile(
+                dir=os.path.dirname(self._cache_filename), delete=False)
+            self._lock_file(new_cache)
             new_cache.write(state)
             new_cache.flush()
             os.fsync(new_cache)
-            os.rename(new_cache_name, self._cache_filename)
+            os.rename(new_cache.name, self._cache_filename)
         except (IOError, OSError, ResumeCacheConflict) as error:
             self.logger.error("There was a problem while saving the cache file: {}".format(error))
             try: