Removed usage of key, now only generate checksum

src/metadata_archivist/archivist.py

@@ -34,8 +34,6 @@
 # "add_description": control boolean to add schema description attributes to resulting metadata. Default True .
 # "add_type": control boolean to add schema type attributes to resulting metadata. Default False .
 # "output_format": "string value of metadata file output format. Default "JSON" .
-# "encoding_key": key used for secure pickle encoding, if None is provided key is autogenerated.
-#                   Path to key file can be provided. Default None .
 DEFAULT_CONFIG = {
     "extraction_directory": ".",
     "output_directory": ".",
@@ -47,7 +45,6 @@
     "add_description": False,
     "add_type": False,
     "output_format": "JSON",
-    "encoding_key": None,
 }
 
 

src/metadata_archivist/formatter.py

@@ -58,7 +58,6 @@ class Formatter:
         add_parser: method to add Parser to list, updates internal schema file.
         update_parser: method to update Parser in list, updates internal schema file.
         remove_parser: method to remove Parser from list, updates internal schema file.
-        get_encoding_key: method to generate encoding key for encoded cache saving.
         get_parser: method to retrieve Parser from list, uses Parser name for matching.
         parse_files: method to trigger parsing procedures on a given list of input files.
         compile_metadata: method to trigger structuring of parsing results.
@@ -112,17 +111,12 @@ def __init__(
         # For parser result caching
         self._cache = helpers.FormatterCache()
 
-        # For securing cached pickles
-        self._encoding_key = None
-
         # Public
         self.config = config
         self.metadata = {}
 
         self.combine = lambda formatter2, schema=None: _combine(formatter1=self, formatter2=formatter2, schema=schema)
 
-        self.get_encoding_key()
-
         if parsers is not None:
             if isinstance(parsers, AParser):
                 self.add_parser(parsers)
@@ -181,32 +175,6 @@ def schema(self, schema: dict) -> None:
             for ex in self._parsers:
                 self._extend_json_schema(ex)
 
-    def get_encoding_key(self) -> bytes:
-        """
-        Method to get or generate encoding key from self contained configuration.
-        If no encoding key provided in the form of a bytes object or path to a binary file then,
-        encoding key is generated from encrypted configuration file.
-        """
-
-        if self._encoding_key is None:
-
-            encoding_key = self.config["encoding_key"]
-            if encoding_key is None:
-                self._encoding_key = sha3_256(p_dumps(self.config, protocol=HIGHEST_PROTOCOL)).digest()
-
-            elif isinstance(encoding_key, bytes):
-                self._encoding_key = encoding_key
-
-            elif isinstance(encoding_key, (str, Path)):
-                with Path(encoding_key).open("rb", encoding=None) as f:
-                    self._encoding_key = f.read()
-
-            else:
-                LOG.debug("config encoding key value '%s'", str(encoding_key))
-                raise ValueError("No appropriate encoding key could be generated.")
-
-        return self._encoding_key
-
     def export_schema(self) -> dict:
         """
         Removes interpretation directives from schema, such that result respects JSONSchema standard.
@@ -406,7 +374,6 @@ def parse_files(
                     entry = self._cache[pid].add(explored_path, file_path)
                     entry.save_metadata(
                         metadata,
-                        self._encoding_key,
                         overwrite=self.config.get("overwrite", True),
                     )
                     meta_files.append(entry.meta_path)
@@ -541,7 +508,7 @@ def compile_metadata(self) -> dict:
                 for cache_entry in parser_cache:
                     update_dict_with_parts(
                         self.metadata,
-                        cache_entry.load_metadata(self._encoding_key),
+                        cache_entry.load_metadata(),
                         list(cache_entry.rel_path.parts),
                     )
         LOG.info("Done!")

src/metadata_archivist/formatting_rules.py

@@ -141,7 +141,7 @@ def _format_parser_id_rule(
             parsed_metadata = []
 
         # Lazy loading handling
-        metadata = cache_entry.load_metadata(formatter.get_encoding_key())
+        metadata = cache_entry.load_metadata()
 
         # Compute additional directives if given
         if parsing_context is not None and "keys" in parsing_context:

src/metadata_archivist/helper_classes.py

@@ -19,7 +19,6 @@
 from json import dumps
 from pathlib import Path
 from hashlib import sha3_256
-from hmac import new, compare_digest
 from typing import Optional, Dict, Union, Any
 from collections.abc import Iterator, ItemsView
 from pickle import loads as p_loads, dumps as p_dumps, HIGHEST_PROTOCOL
@@ -69,15 +68,12 @@ def __init__(self, explored_path: Path, file_path: Path, metadata: Optional[dict
         self.meta_path = Path(str(file_path) + ".meta.pkl")
         self._digest = None
 
-    def load_metadata(self, key: bytes) -> dict:
+    def load_metadata(self) -> dict:
         """
         Loads cached metadata.
         If no cache exists this implies that lazy loading is enabled,
         metadata is loaded then from the self generated meta path.
 
-        Arguments:
-            key: bytes key used to secure pickled file.
-
         Returns:
             self contained parsed metadata dictionary.
         """
@@ -90,8 +86,8 @@ def load_metadata(self, key: bytes) -> dict:
 
             with self.meta_path.open("rb", encoding=None) as f:
                 bytes_read = f.read()
-                new_digest = new(key, bytes_read, sha3_256).hexdigest()
-                if compare_digest(self._digest, new_digest):
+                new_digest = sha3_256(bytes_read).hexdigest()
+                if new_digest == self._digest:
                     self.metadata = p_loads(bytes_read)
                 else:
                     raise ValueError("Encoded pickle has been tampered with.")
@@ -103,13 +99,12 @@ def load_metadata(self, key: bytes) -> dict:
 
         return self.metadata
 
-    def save_metadata(self, metadata: dict, key: bytes, overwrite: bool = True) -> None:
+    def save_metadata(self, metadata: dict, overwrite: bool = True) -> None:
         """
         Saves metadata to file and releases object from memory.
 
         Arguments:
             metadata: dictionary to save.
-            key: bytes key used to secure pickled file.
             overwrite_meta_files : control boolean to enable overwriting of lazy load cache files.
         """
 
@@ -124,7 +119,7 @@ def save_metadata(self, metadata: dict, key: bytes, overwrite: bool = True) -> N
                 raise FileExistsError("Unable to save parsed metadata; overwriting not allowed.")
 
         pickle_dump = p_dumps(metadata, protocol=HIGHEST_PROTOCOL)
-        self._digest = new(key, pickle_dump, sha3_256).hexdigest()
+        self._digest = sha3_256(pickle_dump).hexdigest()
 
         with self.meta_path.open("wb", encoding=None) as f:
             f.write(pickle_dump)