add version control and more verbose error return

Dockerfile

@@ -5,6 +5,9 @@ FROM python:3.12-slim-bullseye
 ARG GITHUB_BUILD=false
 ENV GITHUB_BUILD=${GITHUB_BUILD}
 
+ARG VERSION
+ENV VERSION=${VERSION}
+
 ENV HOME=/root
 ENV \
     DEBIAN_FRONTEND=noninteractive \

src/models/requests.py

@@ -6,6 +6,8 @@ from typing import Any
 
 from pydantic import BaseModel, Field
 
+from src.utils import consts
+
 
 class LinkRequest(BaseModel):
     cmd: str = "get"
@@ -26,9 +28,14 @@ class Solution(BaseModel):
     response: str
 
     @classmethod
-    def empty(cls):
+    def invalid(cls, url: str):
+        """
+        Return an empty Solution with default values.
+
+        Useful for returning an error response.
+        """
         return cls(
-            url="",
+            url=url,
             status=HTTPStatus.INTERNAL_SERVER_ERROR,
             cookies=[],
             userAgent="",
@@ -43,19 +50,23 @@ class LinkResponse(BaseModel):
     solution: Solution
     startTimestamp: int  # noqa: N815 # Ignore to preserve compatibility
     endTimestamp: int = int(time.time() * 1000)  # noqa: N815 # Ignore to preserve compatibility
-    version: str = "3.3.21"  # TODO: Implement versioning
+    version: str = consts.VERSION
 
     @classmethod
-    def invalid(cls):
+    def invalid(cls, url: str):
+        """
+        Return an invalid LinkResponse with default error values.
+
+        This method is used to generate a response indicating an invalid request.
+        """
         return cls(
             status="error",
             message="Invalid request",
-            solution=Solution.empty(),
+            solution=Solution.invalid(url),
             startTimestamp=int(time.time() * 1000),
             endTimestamp=int(time.time() * 1000),
-            version="3.3.21",
         )
 
 
 class NoChromeExtensionError(Exception):
-    """No chrome extention found."""
+    """No chrome extension found."""

src/utils/consts.py

@@ -1,9 +1,33 @@
 import logging
 import os
 
+
+def get_version_from_env():
+    """
+    Retrieve the version from the environment variable 'VERSION'.
+
+    This function checks the 'VERSION' environment variable for a value
+    that starts with 'v' and returns the version without the prefix.
+
+    Returns:
+        str | None: The version string without the 'v' prefix, or None if
+        the 'VERSION' environment variable is not set or does not start
+        with 'v'.
+
+    """
+    version_env = os.getenv("VERSION")
+    if not version_env or not version_env.startswith("v"):
+        return None
+
+    return version_env.removeprefix("v")
+
+
 LOG_LEVEL = os.getenv("LOG_LEVEL") or "INFO"
 LOG_LEVEL = logging.getLevelNamesMapping()[LOG_LEVEL.upper()]
 
+VERSION = get_version_from_env() or "unknown"
+
+
 CHALLENGE_TITLES = [
     # Cloudflare
     "Just a moment...",