Refactor and Enhance Docker Scout Integration (#322)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Co-authored-by: Ryan Mast <[email protected]>

surfactant/infoextractors/docker_image.py

@@ -6,59 +6,79 @@
 import json
 import subprocess
 import tempfile
+from typing import Optional
 
 from loguru import logger
 
 import surfactant.plugin
 from surfactant.sbomtypes import SBOM, Software
 
 
-def is_docker_scout_installed():
-    # Check that Docker Scout can be run
-    try:
-        result = subprocess.run(["docker", "scout"], capture_output=True, check=False)
-        if result.returncode != 0:
+class DockerScoutManager:
+    def __init__(self) -> None:
+        self.disable_docker_scout = True
+        self.docker_scout_installed = False
+
+    def check_docker_scout_installed(self) -> None:
+        """Check if Docker Scout is installed and update the state accordingly."""
+        try:
+            result = subprocess.run(["docker", "scout"], capture_output=True, check=False)
+            self.docker_scout_installed = result.returncode == 0
+        except FileNotFoundError:
+            self.docker_scout_installed = False
+
+        self.disable_docker_scout = not self.docker_scout_installed
+        if not self.docker_scout_installed:
             logger.warning("Install Docker Scout to scan containers for additional information")
-            return False
-        return True
-    except FileNotFoundError:
-        return False
+
+    def run_docker_scout(self, filename: str) -> object:
+        """Run Docker Scout on the given file and return the results."""
+        try:
+            result = subprocess.run(
+                ["docker", "scout", "sbom", "--format", "spdx", f"fs://{filename}"],
+                capture_output=True,
+                check=False,
+            )
+            if result.returncode != 0:
+                logger.warning(f"Running Docker Scout on {filename} failed")
+                return {}
+            spdx_out = json.loads(result.stdout)
+            return {"dockerSPDX": spdx_out}
+        except json.JSONDecodeError as e:
+            logger.error(f"Failed to parse Docker Scout output for {filename}: {e}")
+            return {}
 
 
-# Check if Docker Scout is installed when this Python module gets loaded
-disable_docker_scout = not is_docker_scout_installed()
+# Initialize DockerScoutManager to check installation status
+dsManager = DockerScoutManager()
 
 
 def supports_file(filetype: str) -> bool:
+    """Check if the file type is supported."""
     return filetype in ("DOCKER_TAR", "DOCKER_GZIP")
 
 
 @surfactant.plugin.hookimpl
 def extract_file_info(sbom: SBOM, software: Software, filename: str, filetype: str) -> object:
-    if disable_docker_scout or not supports_file(filetype):
+    """Extract file information using Docker Scout if supported."""
+    if dsManager.disable_docker_scout or not supports_file(filetype):
         return None
     return extract_docker_info(filetype, filename)
 
 
 def extract_docker_info(filetype: str, filename: str) -> object:
+    """Extract Docker information based on file type."""
     if filetype == "DOCKER_GZIP":
         with open(filename, "rb") as gzip_in:
             gzip_data = gzip_in.read()
         with tempfile.NamedTemporaryFile() as gzip_out:
             gzip_out.write(gzip.decompress(gzip_data))
-            return run_docker_scout(gzip_out.name)
-    return run_docker_scout(filename)
-
-
-# Function that extract_docker_info delegates to to actually run Docker scout
-def run_docker_scout(filename: str) -> object:
-    result = subprocess.run(
-        ["docker", "scout", "sbom", "--format", "spdx", f"fs://{filename}"],
-        capture_output=True,
-        check=False,
-    )
-    if result.returncode != 0:
-        logger.warning(f"Running Docker Scout on {filename} failed")
-        return {}
-    spdx_out = json.loads(result.stdout)
-    return {"dockerSPDX": spdx_out}
+            gzip_out.flush()  # Ensure data is written before reading
+            return dsManager.run_docker_scout(gzip_out.name)
+    return dsManager.run_docker_scout(filename)
+
+
+@surfactant.plugin.hookimpl
+def init_hook(command_name: Optional[str] = None) -> None:
+    if command_name != "update-db":
+        dsManager.check_docker_scout_installed()