add Index dataclass

dictdatabase/dataclasses.py

@@ -6,3 +6,14 @@ class SearchResult:
     start_byte: int
     end_byte: int
     found: bool
+
+
+@dataclasses.dataclass(frozen=True)
+class Index:
+    key: str
+    key_start: int
+    key_end: int
+    indent_level: int
+    indent_with: str
+    value_hash: str
+    old_value_end: int

dictdatabase/index_manager.py

@@ -1,28 +1,27 @@
 import hashlib
 
 from dictdatabase import utils
+from dictdatabase.dataclasses import Index
 
 
-class IndexManager:
-    @staticmethod
-    def create_index(all_file_bytes: bytes, key: str, start, end):
-        """
-        It takes a JSON file, a key, and a start and end position, and returns a tuple of information about the key and its
-        value
+def create_index(all_file_bytes: bytes, key: str, start, end) -> Index:
+    """
+    It takes a JSON file, a key, and a start and end position, and returns a tuple of information about the key and its
+    value
 
-        Args:
-          all_file_bytes (bytes): The entire file as a byte string.
-          key (str): The key of the value we're indexing.
-          start: the start of the value in the file
-          end: the end of the value in the file
+    Args:
+      all_file_bytes (bytes): The entire file as a byte string.
+      key (str): The key of the value we're indexing.
+      start: the start of the value in the file
+      end: the end of the value in the file
 
-        Returns:
-          The key, start, end, indent_level, indent_with, value_hash, end
-        """
-        key_start, key_end = utils.find_outermost_key_in_json_bytes(all_file_bytes, key)
-        indent_level, indent_with = utils.detect_indentation_in_json_bytes(
-            all_file_bytes, key_start
-        )
-        value_bytes = all_file_bytes[start:end]
-        value_hash = hashlib.sha256(value_bytes).hexdigest()
-        return key, start, end, indent_level, indent_with, value_hash, end
+    Returns:
+      The key, start, end, indent_level, indent_with, value_hash, end
+    """
+    key_start, key_end = utils.find_outermost_key_in_json_bytes(all_file_bytes, key)
+    indent_level, indent_with = utils.detect_indentation_in_json_bytes(
+        all_file_bytes, key_start
+    )
+    value_bytes = all_file_bytes[start:end]
+    value_hash = hashlib.sha256(value_bytes).hexdigest()
+    return Index(key, start, end, indent_level, indent_with, value_hash, end)

dictdatabase/indexing.py

@@ -3,6 +3,7 @@
 import orjson
 
 from . import config
+from .dataclasses import Index
 
 
 # Problem: Multiple read processes will concurrently read and write the same file
@@ -25,61 +26,65 @@
 
 
 class Indexer:
-	"""
-		The Indexer takes the name of a database file, and tries to load the .index file
-		of the corresponding database file.
-
-		The name of the index file is the name of the database file, with the extension
-		.index and all "/" replaced with "___"
-
-		The content of the index file is a json object, where the keys are keys inside
-		the database json file, and the values are lists of 5 elements:
-		- start_index: The index of the first byte of the value of the key in the database file
-		- end_index: The index of the last byte of the value of the key in the database file
-		- indent_level: The indent level of the key in the database file
-		- indent_with: The indent string used.
-		- value_hash: The hash of the value bytes
-	"""
-
-	__slots__ = ("data", "path")
-
-	def __init__(self, db_name: str):
-		# Make path of index file
-		db_name = db_name.replace("/", "___")
-		self.path = os.path.join(config.storage_directory, ".ddb", f"{db_name}.index")
-
-		os.makedirs(os.path.dirname(self.path), exist_ok=True)
-		if not os.path.exists(self.path):
-			self.data = {}
-			return
-
-		try:
-			with open(self.path, "rb") as f:
-				self.data = orjson.loads(f.read())
-		except orjson.JSONDecodeError:
-			self.data = {}
-
-
-	def get(self, key):
-		"""
-			Returns a list of 5 elements for a key if it exists, otherwise None
-			Elements:[start_index, end_index, indent_level, indent_with, value_hash]
-		"""
-		return self.data.get(key, None)
-
-
-	def write(self, key, start_index, end_index, indent_level, indent_with, value_hash, old_value_end):
-		"""
-			Write index information for a key to the index file
-		"""
-
-		if self.data.get(key, None) is not None:
-			delta = end_index - old_value_end
-			for entry in self.data.values():
-				if entry[0] > old_value_end:
-					entry[0] += delta
-					entry[1] += delta
-
-		self.data[key] = [start_index, end_index, indent_level, indent_with, value_hash]
-		with open(self.path, "wb") as f:
-			f.write(orjson.dumps(self.data))
+    """
+    The Indexer takes the name of a database file, and tries to load the .index file
+    of the corresponding database file.
+
+    The name of the index file is the name of the database file, with the extension
+    .index and all "/" replaced with "___"
+
+    The content of the index file is a json object, where the keys are keys inside
+    the database json file, and the values are lists of 5 elements:
+    - start_index: The index of the first byte of the value of the key in the database file
+    - end_index: The index of the last byte of the value of the key in the database file
+    - indent_level: The indent level of the key in the database file
+    - indent_with: The indent string used.
+    - value_hash: The hash of the value bytes
+    """
+
+    __slots__ = ("data", "path")
+
+    def __init__(self, db_name: str):
+        # Make path of index file
+        db_name = db_name.replace("/", "___")
+        self.path = os.path.join(config.storage_directory, ".ddb", f"{db_name}.index")
+
+        os.makedirs(os.path.dirname(self.path), exist_ok=True)
+        if not os.path.exists(self.path):
+            self.data = {}
+            return
+
+        try:
+            with open(self.path, "rb") as f:
+                self.data = orjson.loads(f.read())
+        except orjson.JSONDecodeError:
+            self.data = {}
+
+    def get(self, key):
+        """
+        Returns a list of 5 elements for a key if it exists, otherwise None
+        Elements:[start_index, end_index, indent_level, indent_with, value_hash]
+        """
+        return self.data.get(key, None)
+
+    def write(self, index: Index):
+        """
+        Write index information for a key to the index file
+        """
+
+        if self.data.get(index.key, None) is not None:
+            delta = index.key_end - index.old_value_end
+            for entry in self.data.values():
+                if entry[0] > index.old_value_end:
+                    entry[0] += delta
+                    entry[1] += delta
+
+        self.data[index.key] = [
+            index.key_start,
+            index.key_end,
+            index.indent_level,
+            index.indent_with,
+            index.value_hash,
+        ]
+        with open(self.path, "wb") as f:
+            f.write(orjson.dumps(self.data))