Fix review comments

cas_wrapper.py

@@ -6,6 +6,9 @@ from pathlib import Path
 
 from plumbum import ProcessExecutionError, local
 
+DEFAULT_BINARY_NAME = "vcn"
+DEFAULT_BINARY_PATH = "/usr/local/bin/"
+
 
 def with_env_context(func):
     @wraps(func)
@@ -30,10 +33,15 @@ class CasWrapper:
     from Codenotary Community Attestation Service
     """
 
-    def _is_binary_present(self):
-        if not self._full_binary_path.exists():
+    @classmethod
+    def _is_binary_present(
+        cls,
+        binary_name: str,
+        binary_path: str,
+    ):
+        if not Path(binary_path, binary_name).exists():
             raise FileNotFoundError(
-                f"Binary VCN is not found in {self._binary_path} on the machine",
+                f"Binary VCN is not found in {binary_path} on the machine",
             )
 
     def __init__(
@@ -42,9 +50,10 @@ class CasWrapper:
         vcn_lc_host: str = "eval-honeywell.codenotary.com",
         vcn_lc_port: int = 443,
         logger: logging.Logger = None,
-        binary_name: str = "vcn",
-        binary_path: str = "/usr/local/bin/",
+        binary_name: str = DEFAULT_BINARY_NAME,
+        binary_path: str = DEFAULT_BINARY_PATH,
     ):
+        self._is_binary_present(binary_name, binary_path)
         self._vcn_lc_api_key = vcn_lc_api_key
         self._vcn_lc_host = vcn_lc_host
         self._vcn_lc_port = vcn_lc_port
@@ -55,11 +64,16 @@ class CasWrapper:
         self._logger = logger
         if self._logger is None:
             self._logger = logging.getLogger()
-        self._is_binary_present()
 
-    def get_version(self):
-        self._is_binary_present()
-        command = self._vcn["--version"]
+    @classmethod
+    def get_version(
+        cls,
+        binary_name: str = DEFAULT_BINARY_NAME,
+        binary_path: str = DEFAULT_BINARY_PATH,
+    ):
+        cls._is_binary_present(binary_name, binary_path)
+        full_path = Path(binary_path, binary_name)
+        command = local[str(full_path)]["--version"]
         version = command().split()[-1].split("v")[1]
         return version