[FUSE]: Generalizing path parsing

favro_sync/favro_fuse.py

@@ -11,52 +11,20 @@ from .favro_client import FavroClient
 from .favro_data_model import Card, SeqId, CustomFieldInfo, CustomFieldItemId, CustomField
 from .favro_markdown import CardContents, CardFileFormatter
 
+################################################################################
+# Constants
+
 logger = getLogger(__name__)
 
 fuse.fuse_python_api = (0, 2)
 
-
-class FavroStat(fuse.Stat):
-    def __init__(self):
-        self.st_mode = 0
-        self.st_ino = 0
-        self.st_dev = 0
-        self.st_nlink = 0
-        self.st_uid = 0
-        self.st_gid = 0
-        self.st_size = 0
-        self.st_atime = 0
-        self.st_mtime = 0
-        self.st_ctime = 0
-
-
+OFFICIAL_URL = 'https://favro.com/organization/{org_id}?card=par-{seq_id}'
 CARD_IDENTIFIER_FORMAT = 'PAR-{seq_id}'
 CARD_FILENAME_FORMAT = CARD_IDENTIFIER_FORMAT + '.md'
-CARD_FILENAME_REGEX = r'^\/PAR\-(\d+)\.md$'
-
-OFFICIAL_URL = 'https://favro.com/organization/{org_id}?card=par-{seq_id}'
-
-
-@dataclasses.dataclass(frozen=True)
-class FileSystemItem:
-    @staticmethod
-    def from_path(path_str: str) -> 'FileSystemItem | None':
-        if path_str == '/':
-            return RootFileSystemItem()
-        if m := re.match(CARD_FILENAME_REGEX, path_str):
-            return CardFileSystemItem(SeqId(int(m.group(1))))
-        return None
-
-
-@dataclasses.dataclass(frozen=True)
-class RootFileSystemItem(FileSystemItem):
-    pass
-
-
-@dataclasses.dataclass(frozen=True)
-class CardFileSystemItem(FileSystemItem):
-    seq_id: SeqId
+CARD_FILENAME_REGEX = r'^PAR\-(\d+)\.md$'
 
+################################################################################
+# Formatting
 
 def to_custom_field_value(custom_field: CustomField, field_def: CustomFieldInfo) -> str:
     value: CustomFieldItemId | list[CustomFieldItemId] = custom_field.value
@@ -107,6 +75,61 @@ def to_card_contents(card: Card, favro_client: FavroClient) -> str:
     )
 
 
+################################################################################
+# FUSE
+
+class FavroStat(fuse.Stat):
+    def __init__(self):
+        self.st_mode = 0
+        self.st_ino = 0
+        self.st_dev = 0
+        self.st_nlink = 0
+        self.st_uid = 0
+        self.st_gid = 0
+        self.st_size = 0
+        self.st_atime = 0
+        self.st_mtime = 0
+        self.st_ctime = 0
+
+
+@dataclasses.dataclass(frozen=True)
+class FileSystemItem:
+    pass
+
+
+@dataclasses.dataclass(frozen=True)
+class RootFileSystemItem(FileSystemItem):
+
+    @staticmethod
+    def from_path_segment(segment: str) -> 'RootFileSystemItem':
+        return RootFileSystemItem()
+
+@dataclasses.dataclass(frozen=True)
+class OrganizationFileSystemItem(FileSystemItem):
+    name: str
+
+    @staticmethod
+    def from_path_segment(segment: str) -> 'OrganizationFileSystemItem':
+        return OrganizationFileSystemItem(segment)
+
+
+@dataclasses.dataclass(frozen=True)
+class CardFileSystemItem(FileSystemItem):
+    seq_id: SeqId
+
+    @staticmethod
+    def from_path_segment(segment: str) -> 'CardFileSystemItem | None':
+        if m := re.match(CARD_FILENAME_REGEX, segment):
+            return CardFileSystemItem(SeqId(int(m.group(1))))
+        return None
+
+
+def path_to_file_system_item(path_str: str, path_components: list[type[FileSystemItem]]) -> FileSystemItem | None:
+    path = re.findall(r'[^/]+', path_str)
+    component = path_components[len(path)]
+    return component.from_path_segment(path[-1] if path else None)
+
+
 class FavroFuse(fuse.Fuse):
     """Favro FileSystem in Userspace."""
 
@@ -119,17 +142,19 @@ class FavroFuse(fuse.Fuse):
         self.favro_client = favro_client
         self.formatter = formatter
         self.wiped_cards = set()
+        #self.path_components = [RootFileSystemItem, OrganizationFileSystemItem, CardFileSystemItem]
+        self.path_components = [RootFileSystemItem, CardFileSystemItem]
         super().__init__(**kwargs)
 
     def getattr(self, path: str) -> FavroStat | int:
-        thing = FileSystemItem.from_path(path)
+        file_system_item = path_to_file_system_item(path, self.path_components)
 
         st = FavroStat()
-        if isinstance(thing, RootFileSystemItem):
+        if isinstance(file_system_item, RootFileSystemItem):
             st.st_mode = stat.S_IFDIR | 0o755
             st.st_nlink = 2
-        elif isinstance(thing, CardFileSystemItem):
-            card = self.favro_client.get_card(thing.seq_id)
+        elif isinstance(file_system_item, CardFileSystemItem):
+            card = self.favro_client.get_card(file_system_item.seq_id)
 
             st.st_mode = stat.S_IFREG | 0o666
             st.st_nlink = 1
@@ -149,18 +174,18 @@ class FavroFuse(fuse.Fuse):
             yield fuse.Direntry(CARD_FILENAME_FORMAT.format(seq_id=card.seq_id.raw_id))
 
     def open(self, path: str, flags: int) -> int | None:
-        thing = FileSystemItem.from_path(path)
-        if not isinstance(thing, CardFileSystemItem):
+        file_system_item = path_to_file_system_item(path, self.path_components)
+        if not isinstance(file_system_item, CardFileSystemItem):
             return -errno.ENOENT
         return None
 
     def read(self, path: str, size: int, offset: int) -> bytes | int:
-        # Check that this is a card thing.
-        thing = FileSystemItem.from_path(path)
-        if not isinstance(thing, CardFileSystemItem):
+        # Check that this is a card file_system_item.
+        file_system_item = path_to_file_system_item(path, self.path_components)
+        if not isinstance(file_system_item, CardFileSystemItem):
             return -errno.ENOENT
 
-        card = self.favro_client.get_card(thing.seq_id)
+        card = self.favro_client.get_card(file_system_item.seq_id)
 
         contents_str = self._format_card_file(card)
         contents = bytes(contents_str, 'utf8')
@@ -175,12 +200,12 @@ class FavroFuse(fuse.Fuse):
         return buf
 
     def write(self, path: str, written_buffer: bytes, offset: int) -> int:
-        # Check that this is a card thing.
-        thing = FileSystemItem.from_path(path)
-        if not isinstance(thing, CardFileSystemItem):
+        # Check that this is a card file_system_item.
+        file_system_item = path_to_file_system_item(path, self.path_components)
+        if not isinstance(file_system_item, CardFileSystemItem):
             return -errno.ENOENT
 
-        card = self.favro_client.get_card(thing.seq_id)
+        card = self.favro_client.get_card(file_system_item.seq_id)
 
         # Splice contents
         contents_str = self._format_card_file(card)
@@ -192,18 +217,18 @@ class FavroFuse(fuse.Fuse):
         card_updated = self.formatter.parse_card_contents(contents_str)
         self.favro_client.update_card_contents(card.card_id, card_updated)
 
-        self.wiped_cards.remove(thing.seq_id)
+        self.wiped_cards.remove(file_system_item.seq_id)
 
         # Return amount written
         return len(written_buffer)
 
     def truncate(self, path: str, new_size: int):
-        # Check that this is a card thing.
-        thing = FileSystemItem.from_path(path)
-        if not isinstance(thing, CardFileSystemItem):
+        # Check that this is a card file_system_item.
+        file_system_item = path_to_file_system_item(path, self.path_components)
+        if not isinstance(file_system_item, CardFileSystemItem):
             return -errno.ENOENT
 
-        card = self.favro_client.get_card(thing.seq_id)
+        card = self.favro_client.get_card(file_system_item.seq_id)
 
         # Splice contents
         contents_str = self._format_card_file(card)
@@ -217,7 +242,7 @@ class FavroFuse(fuse.Fuse):
         card_updated = self.formatter.parse_card_contents(contents_str)
         self.favro_client.update_card_contents_locally(card.card_id, card_updated)
 
-        self.wiped_cards.add(thing.seq_id)
+        self.wiped_cards.add(file_system_item.seq_id)
 
         # Return amount written
         return 0