rgw: improve support for Swift's object versioning.

This patch allows RadosGW to pass the RefStack with an accuracy
to the RFC7230 violation issue which is clearly a Tempest bug.

Fixes: http://tracker.ceph.com/issues/15925
Signed-off-by: Radoslaw Zarzynski <rzarzynski@mirantis.com>
(cherry picked from commit 237ad12)

Conflicts:
	src/rgw/rgw_op.cc
          In contrast to master, Jewel doesn't support
          container quota of Swift API. All tracks of this
          feature have been eradicated from the patch.
	src/rgw/rgw_rest_swift.cc
          Jewel doesn't include boost/optional.hpp but has
          boost/utility/in_place_factory.hpp. The conflict
          has been resolved to pull in both headers.

doc/radosgw/config-ref.rst

@@ -778,6 +778,20 @@ Swift Settings
 :Default: ``auth``
 
 
+``rgw swift versioning enabled``
+
+:Description: Enables the Object Versioning of OpenStack Object Storage API.
+              This allows clients to put the ``X-Versions-Location`` attribute
+              on containers that should be versioned. The attribute specifies
+              the name of container storing archived versions. It must be owned
+              by the same user that the versioned container due to access
+              control verification - ACLs are NOT taken into consideration.
+              Those containers cannot be versioned by the S3 object versioning
+              mechanism.
+:Type: Boolean
+:Default: ``false``
+
+
 
 Logging Settings
 ================

doc/radosgw/swift.rst

@@ -67,7 +67,7 @@ The following table describes the support status for current Swift functional fe
 +---------------------------------+-----------------+----------------------------------------+
 | **Expiring Objects**            | Supported       |                                        |
 +---------------------------------+-----------------+----------------------------------------+
-| **Object Versioning**           | Not Supported   |                                        |
+| **Object Versioning**           | Supported   |                                        |
 +---------------------------------+-----------------+----------------------------------------+
 | **CORS**                        | Not Supported   |                                        |
 +---------------------------------+-----------------+----------------------------------------+

src/rgw/rgw_common.h

@@ -992,11 +992,14 @@ struct RGWBucketInfo
 
   void decode_json(JSONObj *obj);
 
-  bool versioned() { return (flags & BUCKET_VERSIONED) != 0; }
+  bool versioned() const { return (flags & BUCKET_VERSIONED) != 0; }
   int versioning_status() { return flags & (BUCKET_VERSIONED | BUCKET_VERSIONS_SUSPENDED); }
   bool versioning_enabled() { return versioning_status() == BUCKET_VERSIONED; }
 
-  bool has_swift_versioning() { return swift_versioning; }
+  bool has_swift_versioning() const {
+    /* A bucket may be versioned through one mechanism only. */
+    return swift_versioning && !versioned();
+  }
 
   RGWBucketInfo() : flags(0), has_instance_obj(false), num_shards(0), bucket_index_shard_hash_type(MOD), requester_pays(false),
                     has_website(false), swift_versioning(false) {}

src/rgw/rgw_op.cc

@@ -2000,10 +2000,17 @@ void RGWCreateBucket::execute()
 
   s->bucket.tenant = s->bucket_tenant; /* ignored if bucket exists */
   s->bucket.name = s->bucket_name;
+
+  /* Handle updates of the metadata for Swift's object versioning. */
+  if (swift_ver_location) {
+    s->bucket_info.swift_ver_location = *swift_ver_location;
+    s->bucket_info.swift_versioning = (! swift_ver_location->empty());
+  }
+
   op_ret = store->create_bucket(*(s->user), s->bucket, zonegroup_id,
-				placement_rule, swift_ver_location, attrs,
-				info, pobjv, &ep_objv, creation_time,
-				pmaster_bucket, true);
+                                placement_rule, s->bucket_info.swift_ver_location,
+                                attrs, info, pobjv, &ep_objv, creation_time,
+                                pmaster_bucket, true);
   /* continue if EEXIST and create_bucket will fail below.  this way we can
    * recover from a partial create by retrying it. */
   ldout(s->cct, 20) << "rgw_create_bucket returned ret=" << op_ret << " bucket=" << s->bucket << dendl;
@@ -2071,6 +2078,12 @@ void RGWCreateBucket::execute()
       prepare_add_del_attrs(s->bucket_attrs, rmattr_names, attrs);
       populate_with_generic_attrs(s, attrs);
 
+      /* Handle updates of the metadata for Swift's object versioning. */
+      if (swift_ver_location) {
+        s->bucket_info.swift_ver_location = *swift_ver_location;
+        s->bucket_info.swift_versioning = (! swift_ver_location->empty());
+      }
+
       op_ret = rgw_bucket_set_attrs(store, s->bucket_info, attrs,
                                     &s->bucket_info.objv_tracker);
     } while (op_ret == -ECANCELED && tries++ < 20);
@@ -2414,6 +2427,18 @@ void RGWPutObj::execute()
 
   processor = select_processor(*static_cast<RGWObjectCtx *>(s->obj_ctx), &multipart);
 
+  /* Handle object versioning of Swift API. */
+  if (! multipart) {
+    rgw_obj obj(s->bucket, s->object);
+    op_ret = store->swift_versioning_copy(*static_cast<RGWObjectCtx *>(s->obj_ctx),
+                                          s->bucket_owner.get_id(),
+                                          s->bucket_info,
+                                          obj);
+    if (op_ret < 0) {
+      return;
+    }
+  }
+
   op_ret = processor->prepare(store, NULL);
   if (op_ret < 0) {
     ldout(s->cct, 20) << "processor->prepare() returned ret=" << op_ret
@@ -2883,8 +2908,10 @@ void RGWPutMetadataBucket::execute()
   prepare_add_del_attrs(s->bucket_attrs, rmattr_names, attrs);
   populate_with_generic_attrs(s, attrs);
 
-  s->bucket_info.swift_ver_location = swift_ver_location;
-  s->bucket_info.swift_versioning = (!swift_ver_location.empty());
+  if (swift_ver_location) {
+    s->bucket_info.swift_ver_location = *swift_ver_location;
+    s->bucket_info.swift_versioning = (! swift_ver_location->empty());
+  }
 
   op_ret = rgw_bucket_set_attrs(store, s->bucket_info, attrs,
 				&s->bucket_info.objv_tracker);
@@ -3056,35 +3083,46 @@ void RGWDeleteObj::execute()
     }
 
     RGWObjectCtx *obj_ctx = static_cast<RGWObjectCtx *>(s->obj_ctx);
-
     obj_ctx->set_atomic(obj);
 
-    RGWRados::Object del_target(store, s->bucket_info, *obj_ctx, obj);
-    RGWRados::Object::Delete del_op(&del_target);
-
-    op_ret = get_system_versioning_params(s, &del_op.params.olh_epoch,
-					  &del_op.params.marker_version_id);
+    bool ver_restored = false;
+    op_ret = store->swift_versioning_restore(*obj_ctx, s->bucket_owner.get_id(),
+                                             s->bucket_info, obj, ver_restored);
     if (op_ret < 0) {
       return;
     }
 
-    del_op.params.bucket_owner = s->bucket_owner.get_id();
-    del_op.params.versioning_status = s->bucket_info.versioning_status();
-    del_op.params.obj_owner = s->owner;
-    del_op.params.unmod_since = unmod_since;
-    del_op.params.high_precision_time = s->system_request; /* system request uses high precision time */
+    if (!ver_restored) {
+      /* Swift's versioning mechanism hasn't found any previous version of
+       * the object that could be restored. This means we should proceed
+       * with the regular delete path. */
+      RGWRados::Object del_target(store, s->bucket_info, *obj_ctx, obj);
+      RGWRados::Object::Delete del_op(&del_target);
 
-    op_ret = del_op.delete_obj();
-    if (op_ret >= 0) {
-      delete_marker = del_op.result.delete_marker;
-      version_id = del_op.result.version_id;
-    }
+      op_ret = get_system_versioning_params(s, &del_op.params.olh_epoch,
+                                            &del_op.params.marker_version_id);
+      if (op_ret < 0) {
+        return;
+      }
 
-    /* Check whether the object has expired. Swift API documentation
-     * stands that we should return 404 Not Found in such case. */
-    if (need_object_expiration() && object_is_expired(attrs)) {
-      op_ret = -ENOENT;
-      return;
+      del_op.params.bucket_owner = s->bucket_owner.get_id();
+      del_op.params.versioning_status = s->bucket_info.versioning_status();
+      del_op.params.obj_owner = s->owner;
+      del_op.params.unmod_since = unmod_since;
+      del_op.params.high_precision_time = s->system_request; /* system request uses high precision time */
+
+      op_ret = del_op.delete_obj();
+      if (op_ret >= 0) {
+        delete_marker = del_op.result.delete_marker;
+        version_id = del_op.result.version_id;
+      }
+
+      /* Check whether the object has expired. Swift API documentation
+       * stands that we should return 404 Not Found in such case. */
+      if (need_object_expiration() && object_is_expired(attrs)) {
+        op_ret = -ENOENT;
+        return;
+      }
     }
 
     if (op_ret == -ERR_PRECONDITION_FAILED && no_precondition_error) {
@@ -3306,6 +3344,16 @@ void RGWCopyObj::execute()
 
   bool high_precision_time = (s->system_request);
 
+  /* Handle object versioning of Swift API. In case of copying to remote this
+   * should fail gently (op_ret == 0) as the dst_obj will not exist here. */
+  op_ret = store->swift_versioning_copy(obj_ctx,
+                                        dest_bucket_info.owner,
+                                        dest_bucket_info,
+                                        dst_obj);
+  if (op_ret < 0) {
+    return;
+  }
+
   op_ret = store->copy_obj(obj_ctx,
 			   s->user->user_id,
 			   client_id,

src/rgw/rgw_op.h

@@ -18,6 +18,8 @@
 #include <set>
 #include <map>
 
+#include <boost/optional.hpp>
+
 #include "common/armor.h"
 #include "common/mime.h"
 #include "common/utf8.h"
@@ -535,7 +537,7 @@ class RGWCreateBucket : public RGWOp {
   obj_version ep_objv;
   bool has_cors;
   RGWCORSConfiguration cors_config;
-  string swift_ver_location;
+  boost::optional<std::string> swift_ver_location;
   map<string, buffer::list> attrs;
   set<string> rmattr_names;
 
@@ -781,7 +783,7 @@ class RGWPutMetadataBucket : public RGWOp {
   RGWAccessControlPolicy policy;
   RGWCORSConfiguration cors_config;
   string placement_rule;
-  string swift_ver_location;
+  boost::optional<std::string> swift_ver_location;
 
 public:
   RGWPutMetadataBucket()