Update libraries (#25)

* Update libraries

* Update unit tests

lib/charms/observability_libs/v0/juju_topology.py

@@ -67,16 +67,15 @@
 ```
 
 """
-
-import re
 from collections import OrderedDict
 from typing import Dict, List, Optional
+from uuid import UUID
 
 # The unique Charmhub library identifier, never change it
 LIBID = "bced1658f20f49d28b88f61f83c2d232"
 
 LIBAPI = 0
-LIBPATCH = 2
+LIBPATCH = 4
 
 
 class InvalidUUIDError(Exception):
@@ -95,8 +94,8 @@ def __init__(
         model: str,
         model_uuid: str,
         application: str,
-        unit: str = None,
-        charm_name: str = None,
+        unit: Optional[str] = None,
+        charm_name: Optional[str] = None,
     ):
         """Build a JujuTopology object.
 
@@ -126,29 +125,18 @@ def __init__(
         self._unit = unit
 
     def is_valid_uuid(self, uuid):
-        """Validate the supplied UUID against the Juju Model UUID pattern."""
-        # TODO:
-        # Harness is harcoding an UUID that is v1 not v4: f2c1b2a6-e006-11eb-ba80-0242ac130004
-        # See: https://github.com/canonical/operator/issues/779
-        #
-        # >>> uuid.UUID("f2c1b2a6-e006-11eb-ba80-0242ac130004").version
-        # 1
-        #
-        # we changed the validation of the 3ed UUID block: 4[a-f0-9]{3} -> [a-f0-9]{4}
-        # See: https://github.com/canonical/operator/blob/main/ops/testing.py#L1094
-        #
-        # Juju in fact generates a UUID v4: https://github.com/juju/utils/blob/master/uuid.go#L62
-        # but does not validate it is actually v4:
-        # See:
-        # - https://github.com/juju/utils/blob/master/uuid.go#L22
-        # - https://github.com/juju/schema/blob/master/strings.go#L79
-        #
-        # Once Harness fixes this, we should remove this comment and refactor the regex or
-        # the entire method using the uuid module to validate UUIDs
-        regex = re.compile(
-            "^[a-f0-9]{8}-?[a-f0-9]{4}-?[a-f0-9]{4}-?[89ab][a-f0-9]{3}-?[a-f0-9]{12}$"
-        )
-        return bool(regex.match(uuid))
+        """Validate the supplied UUID against the Juju Model UUID pattern.
+
+        Args:
+            uuid: string that needs to be checked if it is valid v4 UUID.
+
+        Returns:
+            True if parameter is a valid v4 UUID, False otherwise.
+        """
+        try:
+            return str(UUID(uuid, version=4)) == uuid
+        except (ValueError, TypeError):
+            return False
 
     @classmethod
     def from_charm(cls, charm):
@@ -193,7 +181,10 @@ def from_dict(cls, data: dict):
         )
 
     def as_dict(
-        self, *, remapped_keys: Dict[str, str] = None, excluded_keys: List[str] = None
+        self,
+        *,
+        remapped_keys: Optional[Dict[str, str]] = None,
+        excluded_keys: Optional[List[str]] = None,
     ) -> OrderedDict:
         """Format the topology information into an ordered dict.