Redirects user to a path that ends in /

This patch returns a 301 redirect when a requested path does not end in a / but should end in a /.

Changes the order in which pulpcore-content looks for published artifacts
The handler now looks for a published artifact before it tries to look for an index.html or listing
the directory.

fixes: pulp#3173
fixes: pulp#3459

CHANGES/3173.feature

@@ -0,0 +1 @@
+Content app now redirects requests without a trailing slash to a path with the trailing slash. 

CHANGES/plugin_api/3459.feature

@@ -0,0 +1,2 @@
+Added a flag `REDIRECT_ON_MISSING_SLASH` for plugin distrubution models to opt out of automatic
+redirecting if a path should end in a slash but does not.

pulpcore/app/models/base.py

@@ -126,6 +126,24 @@ class MasterModel(BaseModel, metaclass=MasterModelMeta):
     class Meta:
         abstract = True
 
+    @classmethod
+    def get_pulp_type(cls):
+        """Get the "pulp_type" string associated with this MasterModel type."""
+        return "{app_label}.{type}".format(app_label=cls._meta.app_label, type=cls.TYPE)
+
+    @classmethod
+    def get_model_for_pulp_type(cls, pulp_type):
+        return cls._pulp_model_map[pulp_type]
+
+    def __init_subclass__(cls, /, **kwargs):
+        super().__init_subclass__(**kwargs)
+        if hasattr(cls, "_pulp_model_map"):
+            # This is a Detail Model. Register it with the Master Model.
+            cls._pulp_model_map[cls.get_pulp_type()] = cls
+        else:
+            # This is a Master Model. Initialize the model map.
+            cls._pulp_model_map = {}
+
     def save(self, *args, **kwargs):
         # instances of "detail" models that subclass MasterModel are exposed
         # on instances of MasterModel by the string stored in that model's TYPE attr.
@@ -137,11 +155,6 @@ def save(self, *args, **kwargs):
             self.pulp_type = self.get_pulp_type()
         return super().save(*args, **kwargs)
 
-    @classmethod
-    def get_pulp_type(cls):
-        """Get the "pulp_type" string associated with this MasterModel type."""
-        return "{app_label}.{type}".format(app_label=cls._meta.app_label, type=cls.TYPE)
-
     def cast(self):
         """Return a "Detail" model instance of this master-detail pair.
 

pulpcore/app/models/publication.py

@@ -524,9 +524,12 @@ class Distribution(MasterModel):
         pulp_domain (models.ForeignKey): The domain the Distribution is a part of.
     """
 
-    # If distribution serves publications, set by subclasses for proper handling in content app
+    # If distribution serves publications, set by subclasses for proper handling in content app.
     SERVE_FROM_PUBLICATION = False
 
+    # Plugins can opt out of redirecting by settings this to False.
+    REDIRECT_ON_MISSING_SLASH = True
+
     name = models.TextField(db_index=True)
     pulp_labels = HStoreField(default=dict)
     base_path = models.TextField()

pulpcore/content/handler.py

@@ -9,6 +9,7 @@
 from aiohttp.web_exceptions import (
     HTTPForbidden,
     HTTPFound,
+    HTTPMovedPermanently,
     HTTPNotFound,
     HTTPRequestRangeNotSatisfiable,
 )
@@ -280,6 +281,9 @@ def _match_distribution(cls, path):
             DistroListings: when multiple matches are possible.
             PathNotResolved: when not matched.
         """
+        path_ends_in_slash = path.endswith("/")
+        if not path_ends_in_slash:
+            path = f"{path}/"
         base_paths = cls._base_paths(path)
         distro_model = cls.distribution_model or Distribution
         domain = get_domain()
@@ -298,8 +302,11 @@ def _match_distribution(cls, path):
                     pulp_domain=domain, base_path__startswith=path
                 )
                 if distros.count():
-                    raise DistroListings(path=path, distros=distros)
-
+                    if path_ends_in_slash:
+                        raise DistroListings(path=path, distros=distros)
+                    else:
+                        # The list of a subset of distributions was requested without a trailing /
+                        raise HTTPMovedPermanently(f"{settings.CONTENT_PATH_PREFIX}{path}")
             log.debug(
                 _("Distribution not matched for {path} using: {base_paths}").format(
                     path=path, base_paths=base_paths
@@ -478,9 +485,7 @@ def list_directory_blocking():
                 ).values_list("content_artifact_id", "size")
                 sizes.update({artifacts_to_find[ra_ca_id]: size for ra_ca_id, size in r_artifacts})
 
-                return directory_list, dates, sizes
-            else:
-                raise PathNotResolved(path)
+            return directory_list, dates, sizes
 
         return await sync_to_async(list_directory_blocking)()
 
@@ -525,6 +530,12 @@ async def _match_and_stream(self, path, request):
         rel_path = rel_path[len(distro.base_path) :]
         rel_path = rel_path.lstrip("/")
 
+        if rel_path == "" and not path.endswith("/"):
+            # The root of a distribution base_path was requested without a slash
+            if not distro.REDIRECT_ON_MISSING_SLASH:
+                raise ObjectDoesNotExist(request.path)
+            raise HTTPMovedPermanently(f"{request.path}/")
+
         content_handler_result = await sync_to_async(distro.content_handler)(rel_path)
         if content_handler_result is not None:
             return content_handler_result
@@ -561,28 +572,6 @@ def get_latest_publication_or_version_blocking():
             await sync_to_async(get_latest_publication_or_version_blocking)()
 
         if publication:
-            if rel_path == "" or rel_path[-1] == "/":
-                try:
-                    index_path = "{}index.html".format(rel_path)
-
-                    await sync_to_async(publication.published_artifact.get)(
-                        relative_path=index_path
-                    )
-
-                    rel_path = index_path
-                    headers = self.response_headers(rel_path)
-                except ObjectDoesNotExist:
-                    dir_list, dates, sizes = await self.list_directory(None, publication, rel_path)
-                    dir_list.update(
-                        await sync_to_async(distro.content_handler_list_directory)(rel_path)
-                    )
-                    return HTTPOk(
-                        headers={"Content-Type": "text/html"},
-                        body=self.render_html(
-                            dir_list, path=request.path, dates=dates, sizes=sizes
-                        ),
-                    )
-
             # published artifact
             try:
 
@@ -638,6 +627,39 @@ def get_contentartifact_blocking():
                             request, StreamResponse(headers=headers), ca
                         )
 
+            # Look for index.html or list the directory
+            ends_in_slash = rel_path == "" or rel_path.endswith("/")
+            if not ends_in_slash:
+                rel_path = f"{rel_path}/"
+            try:
+                index_path = "{}index.html".format(rel_path)
+
+                await sync_to_async(publication.published_artifact.get)(relative_path=index_path)
+                if ends_in_slash is False:
+                    # index.html found, but user didn't specify a trailing slash
+                    if not distro.REDIRECT_ON_MISSING_SLASH:
+                        raise ObjectDoesNotExist(request.path)
+                    raise HTTPMovedPermanently(f"{request.path}/")
+                rel_path = index_path
+                headers = self.response_headers(rel_path)
+            except ObjectDoesNotExist:
+                if not distro.REDIRECT_ON_MISSING_SLASH:
+                    raise
+                dir_list, dates, sizes = await self.list_directory(None, publication, rel_path)
+                dir_list.update(
+                    await sync_to_async(distro.content_handler_list_directory)(rel_path)
+                )
+                if dir_list and not ends_in_slash:
+                    # Directory can be listed, but user did not specify trailing slash
+                    raise HTTPMovedPermanently(f"{request.path}/")
+                elif dir_list:
+                    return HTTPOk(
+                        headers={"Content-Type": "text/html"},
+                        body=self.render_html(
+                            dir_list, path=request.path, dates=dates, sizes=sizes
+                        ),
+                    )
+
         if repo_version and not publication and not distro.SERVE_FROM_PUBLICATION:
             if rel_path == "" or rel_path[-1] == "/":
                 index_path = "{}index.html".format(rel_path)