adding new way to read from tar files

src/confcom/azext_confcom/os_util.py

@@ -95,7 +95,7 @@ def load_tar_mapping_from_file(path: str) -> dict:
     return raw_json
 
 
-def map_image_from_tar(image_name: str, tar: TarFile, tar_location: str):
+def map_image_from_tar_backwards_compatibility(image_name: str, tar: TarFile, tar_location: str):
     tar_dir = os.path.dirname(tar_location)
     # grab all files in the folder and only take the one that's named with hex values and a json extension
     members = tar.getmembers()
@@ -139,3 +139,41 @@ def map_image_from_tar(image_name: str, tar: TarFile, tar_location: str):
     image_info["Architecture"] = image_info_raw.get("architecture")
 
     return image_info
+
+
+def map_image_from_tar(image_name: str, tar: TarFile, tar_location: str):
+    tar_dir = os.path.dirname(tar_location)
+    info_file = None
+    info_file_name = "manifest.json"
+    # if there's more than one image in the tarball, we need to do some more logic
+    if len(info_file_name) > 0:
+        # extract just the manifest file and see if any of the RepoTags match the image_name we're searching for
+        # the manifest.json should have a list of all the image tags
+        # and what json files they map to to get env vars, startup cmd, etc.
+        tar.extract(info_file_name, path=tar_dir)
+        manifest_path = os.path.join(tar_dir, info_file_name)
+        manifest = load_json_from_file(manifest_path)
+        # if we match a RepoTag to the image, stop searching
+        for image in manifest:
+            if image_name in image.get("RepoTags"):
+                info_file = image.get("Config")
+                break
+        # remove the extracted manifest file to clean up
+        os.remove(manifest_path)
+    else:
+        eprint(f"Tarball at {tar_location} contains no images")
+
+    if not info_file:
+        return None
+    tar.extract(info_file, path=tar_dir)
+
+    # get the path of the json file and read it in
+    image_info_file_path = os.path.join(tar_dir, info_file)
+    image_info_raw = load_json_from_file(image_info_file_path)
+    # delete the extracted json file to clean up
+    os.remove(image_info_file_path)
+    image_info = image_info_raw.get("config")
+    # importing the constant from config.py gives a circular dependency error
+    image_info["Architecture"] = image_info_raw.get("architecture")
+
+    return image_info

src/confcom/azext_confcom/security_policy.py

@@ -412,7 +412,7 @@ def populate_policy_content_for_all_images(
                         image.set_command(command)
 
                     # merge envs for user container image
-                    envs = image_info.get("Env")
+                    envs = image_info.get("Env") or []
                     env_names = [
                         env_var[
                             config.POLICY_FIELD_CONTAINERS_ELEMENTS_ENVS_RULE

src/confcom/azext_confcom/template_util.py

@@ -81,9 +81,14 @@ def get_image_info(progress, message_queue, tar_mapping, image):
         if tar_location:
             with tarfile.open(tar_location) as tar:
                 # get all the info out of the tarfile
-                image_info = os_util.map_image_from_tar(
-                    image_name, tar, tar_location
-                )
+                try:
+                    image_info = os_util.map_image_from_tar_backwards_compatibility(
+                        image_name, tar, tar_location
+                    )
+                except IndexError:
+                    image_info = os_util.map_image_from_tar(
+                        image_name, tar, tar_location
+                    )
                 if image_info is not None:
                     tar = True
                     message_queue.append(f"{image_name} read from local tar file")

src/confcom/azext_confcom/tests/latest/test_confcom_scenario.py

@@ -635,7 +635,7 @@ def test_docker_pull(self):
 
             self.assertEqual(
                 image.id,
-                "sha256:e525c930fe751104ff24c356a7bcfad66ce4b92797780eb38dc2ff95d7a66fdc",
+                "sha256:d49a5025be10344cce77d178103a225cb5d7316861e5d8f106e7ff278ae51b62",
             )
 
     def test_infrastructure_svn(self):