file_manager: save metadata to the database

This allows gcode file metadata to persist through restarts, reducing the time spent parsing.  The gcode file path also persists, so it is available even when Klippy is not.

Signed-off-by:  Eric Callahan <arksine.code@gmail.com>

moonraker/plugins/file_manager.py

@@ -22,7 +22,9 @@ class FileManager:
     def __init__(self, config):
         self.server = config.get_server()
         self.file_paths = {}
-        self.gcode_metadata = MetadataStorage(self.server)
+        database = self.server.load_plugin(config, "database")
+        gc_path = database.get_item("moonraker", "file_manager.gcode_path", "")
+        self.gcode_metadata = MetadataStorage(self.server, gc_path, database)
         self.fixed_path_args = {}
 
         # Register file management endpoints
@@ -58,6 +60,10 @@ class FileManager:
                 raise config.error(
                     "Option 'config_path' is not a valid directory")
 
+        # If gcode path is in the database, register it
+        if gc_path:
+            self.register_directory('gcodes', gc_path)
+
     def _update_fixed_paths(self):
         kinfo = self.server.get_klippy_info()
         paths = {k: kinfo.get(k) for k in
@@ -108,7 +114,10 @@ class FileManager:
             self.file_paths[root] = path
             self.server.register_static_file_handler(root, path)
             if root == "gcodes":
-                # scan metadata
+                database = self.server.lookup_plugin(
+                    "database").wrap_namespace("moonraker")
+                database["file_manager.gcode_path"] = path
+                # scan for metadata changes
                 self.gcode_metadata.update_gcode_path(path)
                 try:
                     self.get_file_list("gcodes")
@@ -612,22 +621,25 @@ class FileManager:
 
 
 METADATA_PRUNE_TIME = 600000
+METADATA_NAMESPACE = "gcode_metadata"
 
 class MetadataStorage:
-    def __init__(self, server):
+    def __init__(self, server, gc_path, database):
         self.server = server
-        self.metadata = {}
+        database.register_local_namespace(METADATA_NAMESPACE)
+        self.mddb = database.wrap_namespace(
+            METADATA_NAMESPACE, parse_keys=False)
         self.pending_requests = {}
         self.events = {}
         self.busy = False
-        self.gc_path = os.path.expanduser("~")
+        self.gc_path = gc_path
         self.prune_cb = PeriodicCallback(
             self.prune_metadata, METADATA_PRUNE_TIME)
 
     def update_gcode_path(self, path):
         if path == self.gc_path:
             return
-        self.metadata = {}
+        self.mddb.clear()
         self.gc_path = path
         if not self.prune_cb.is_running():
             self.prune_cb.start()
@@ -636,27 +648,28 @@ class MetadataStorage:
         self.prune_cb.stop()
 
     def get(self, key, default=None):
-        if key not in self.metadata:
-            return default
-        return dict(self.metadata[key])
+        return self.mddb.get(key, default)
 
     def __getitem__(self, key):
-        return dict(self.metadata[key])
+        return self.mddb[key]
 
     def prune_metadata(self):
-        for fname in list(self.metadata.keys()):
+        for fname in list(self.mddb.keys()):
             fpath = os.path.join(self.gc_path, fname)
             if not os.path.exists(fpath):
-                del self.metadata[fname]
+                del self.mddb[fname]
                 logging.info(f"Pruned file: {fname}")
                 continue
 
     def _has_valid_data(self, fname, fsize, modified):
-        mdata = self.metadata.get(fname, {'size': "", 'modified': 0})
+        mdata = self.mddb.get(fname, {'size': "", 'modified': 0})
         return mdata['size'] == fsize and mdata['modified'] == modified
 
     def remove_file(self, fname):
-        self.metadata.pop(fname)
+        try:
+            del self.mddb[fname]
+        except Exception:
+            pass
 
     def parse_metadata(self, fname, fsize, modified, notify=False):
         evt = Event()
@@ -689,7 +702,7 @@ class MetadataStorage:
                 else:
                     break
             else:
-                self.metadata[fname] = {'size': fsize, 'modified': modified}
+                self.mddb[fname] = {'size': fsize, 'modified': modified}
                 logging.info(
                     f"Unable to extract medatadata from file: {fname}")
             evt.set()
@@ -716,7 +729,7 @@ class MetadataStorage:
         if not metadata:
             # This indicates an error, do not add metadata for this
             raise self.server.error("Unable to extract metadata")
-        self.metadata[path] = dict(metadata)
+        self.mddb[path] = dict(metadata)
         metadata['filename'] = path
         if notify:
             self.server.send_event(