if ok {
		return b.updateCacheEntry(update)
	}

	// We should have either a trashed bucket or this
	return metacache{}, errVolumeNotFound
}

// getBucket will get a bucket metacache or load it from disk if needed.
func (m *metacacheManager) getBucket(ctx context.Context, bucket string) *bucketMetacache {
	m.init.Do(m.initManager)

	// Return a transient bucket for invalid or system buckets.
	m.mu.RLock()

        ],
        "Effect": "Allow",
        "Sid": ""
     }, 
     {
      "Effect": "Allow",
      "Action": [
       "s3:GetReplicationConfiguration",
       "s3:PutReplicationConfiguration",
       "s3:ListBucket",
       "s3:ListBucketMultipartUploads",
       "s3:GetBucketLocation",
       "s3:GetBucketVersioning"
      ],
      "Resource": [
       "arn:aws:s3:::bucket"
      ]
     }
    ]
   }
EOF

```
{
  "Version": "2012-10-17",
  "Statement": [
	{
	  "Action": ["s3:ListBucket"],
	  "Effect": "Allow",
	  "Resource": ["arn:aws:s3:::mybucket"],
	  "Condition": {"StringLike": {"s3:prefix": ["${aws:username}/*"]}}
	},
	{
	  "Action": [
		"s3:GetObject",
		"s3:PutObject"
	  ],

        failure.assertHasCause("403 Forbidden")
    }

    MavenGcsRepository getMavenGcsRepo() {
        new MavenGcsRepository(server, file(getTestDirectory()), getRepositoryPath(), getBucket())
    }

    }

    MavenS3Repository getMavenS3Repo() {
        new MavenS3Repository(server, file(getTestDirectory()), getRepositoryPath(), getBucket())
    }

The JSON body structure can be seen from this sample:

<details><summary>Request Body Sample</summary>

```json
{
  "input": {
    "account": "minio",
    "groups": null,
    "action": "s3:ListBucket",
    "bucket": "test",
    "conditions": {
      "Authorization": [

	policy := "mypolicy"
	policyBytes := []byte(fmt.Sprintf(`{
 "Version": "2012-10-17",
 "Statement": [
  {
   "Effect": "Allow",
   "Action": [
    "s3:PutObject",
    "s3:GetObject",
    "s3:ListBucket"
   ],
   "Resource": [
    "arn:aws:s3:::%s/*"
   ]
  }
 ]
}`, bucket))
	err = s.adm.AddCannedPolicy(ctx, policy, policyBytes)
	if err != nil {
		c.Fatalf("policy add error: %v", err)
	}

            Storage.Objects.Insert putRequest = storage.objects().insert(bucket, objectMetadata, contentStream);

            LOGGER.debug("Attempting to put resource:[{}] into gcs bucket [{}]", putRequest.getName(), putRequest.getBucket());
            putRequest.execute();
        } catch (IOException e) {
            throw ResourceExceptions.putFailed(destination, e);
        }
    }

    @Nullable

			Principal: miniogopolicy.User{AWS: set.CreateStringSet("*")},
			Resources: set.CreateStringSet(policy.NewResource(bucketName).String()),
			Actions:   set.CreateStringSet("s3:GetBucketLocation", "s3:ListBucket"),
		},
		{
			Effect:    string(policy.Allow),
			Principal: miniogopolicy.User{AWS: set.CreateStringSet("*")},
			Resources: set.CreateStringSet(policy.NewResource(bucketName + "/" + prefix).String()),

				t.Errorf("Expected failed but succeeded")
			}
		})
	}
}

// Test Post Policy parsing and checking conditions
func TestPostPolicyForm(t *testing.T) {
	pp := minio.NewPostPolicy()
	pp.SetBucket("testbucket")
	pp.SetContentType("image/jpeg")
	pp.SetUserMetadata("uuid", "14365123651274")
	pp.SetKeyStartsWith("user/user1/filename")
	pp.SetContentLengthRange(1048579, 10485760)
	pp.SetSuccessStatusAction("201")