Remove the manifest schema conversion machinery

closes: pulp#1509

CHANGES/1509.removal

@@ -0,0 +1,2 @@
+Removed the manifest schema conversion machinery. This change also removes the ``pyjwkest``
+dependency, since it is not used anymore.

docs/workflows/host.rst

@@ -113,10 +113,8 @@ Docker Output::
 
 .. note::
     When using a container client that cannot handle requested manifests in the new format
-    (schema 2), the manifests are rewritten into the old format (schema 1) on-the-fly by Pulp.
-    In general, the automatic conversion cannot be performed when the content is not available
-    in the storage. Therefore, it may be successful only if the content was previously synced
-    with the ``immediate`` policy.
+    (schema 2), the manifests will **not** be rewritten into the old format (schema 1) and Pulp will
+    raise a 404 (HTTPNOTFOUND) error.
 
 
 Pull-Through Caching

pulp_container/app/registry.py

@@ -24,7 +24,6 @@
 
 from pulp_container.app.cache import RegistryContentCache
 from pulp_container.app.models import ContainerDistribution, Tag, Blob, Manifest, BlobManifest
-from pulp_container.app.schema_convert import Schema2toSchema1ConverterWrapper
 from pulp_container.app.tasks import download_image_data
 from pulp_container.app.utils import (
     calculate_digest,
@@ -212,8 +211,8 @@ async def get_tag(self, request):
             }
             return await self.dispatch_tag(request, tag, response_headers)
 
-        # convert if necessary
-        return await Registry.dispatch_converted_schema(tag, accepted_media_types, path)
+        # return 404 in case the client is requesting docker manifest v2 schema 1
+        raise PathNotResolved(tag_name)
 
     async def dispatch_tag(self, request, tag, response_headers):
         """
@@ -239,40 +238,6 @@ async def dispatch_tag(self, request, tag, response_headers):
         else:
             return await Registry._dispatch(artifact, response_headers)
 
-    @staticmethod
-    async def dispatch_converted_schema(tag, accepted_media_types, path):
-        """
-        Convert a manifest from the format schema 2 to the format schema 1.
-
-        The format is converted on-the-go and created resources are not stored for further uses.
-        The conversion is made after each request which does not accept the format for schema 2.
-
-        Args:
-            tag: A tag object which contains reference to tagged manifests and config blobs.
-            accepted_media_types: Accepted media types declared in the accept header.
-            path: A path of a repository.
-
-        Raises:
-            PathNotResolved: There was not found a valid conversion for the specified tag.
-
-        Returns:
-            :class:`aiohttp.web.StreamResponse` or :class:`aiohttp.web.Response`: The response
-                streamed back to the client.
-
-        """
-        schema1_converter = Schema2toSchema1ConverterWrapper(tag, accepted_media_types, path)
-        try:
-            result = await sync_to_async(schema1_converter.convert)()
-        except RuntimeError:
-            raise PathNotResolved(tag.name)
-
-        response_headers = {
-            "Docker-Content-Digest": result.digest,
-            "Content-Type": result.content_type,
-            "Docker-Distribution-API-Version": "registry/2.0",
-        }
-        return web.Response(text=result.text, headers=response_headers)
-
     @RegistryContentCache(
         base_key=lambda req, cac: Registry.find_base_path_cached(req, cac),
         auth=lambda req, cac, bk: Registry.auth_cached(req, cac, bk),

pulp_container/tests/functional/api/test_content_cache.py

@@ -26,6 +26,9 @@
     get_auth_for_url,
 )
 
+
+from pulp_container.constants import MEDIA_TYPE
+
 STANDARD_FILE_STORAGE_FRAMEWORKS = [
     "django.core.files.storage.FileSystemStorage",
     "pulpcore.app.models.storage.FileSystem",
@@ -112,7 +115,10 @@ def test_04_multiple_distributions(self):
     def test_05_different_headers(self):
         """Simulate a scenario where a user queries manifests with different Accept headers."""
         self.check_content(cache_status_found_func)
-        self.check_content(cache_status_first_func, headers={"Accept": "*/*"})
+        self.check_content(
+            cache_status_first_func,
+            headers={"Accept": f"{MEDIA_TYPE.INDEX_OCI},{MEDIA_TYPE.MANIFEST_LIST}"},
+        )
 
     def test_06_invalidate_multiple_distributions(self):
         """Test if updating the repository referenced by multiple distributions invalidates all."""