Support the new API GetObjectAttributes

Issue: CLDSRV-817

Author: maeldonn

constants.js

@@ -279,6 +279,14 @@ const constants = {
     rateLimitDefaultConfigCacheTTL: 30000, // 30 seconds
     rateLimitDefaultBurstCapacity: 1,
     rateLimitCleanupInterval: 10000, // 10 seconds
+    // Metadata allowed to be returned by getObjectAttributes API
+    allowedObjectAttributes: new Set([
+        'StorageClass',
+        'ObjectSize',
+        'ObjectParts',
+        'Checksum',
+        'ETag',
+    ]),
 };
 
 module.exports = constants;

lib/api/api.js

@@ -56,6 +56,7 @@ const { objectDelete } = require('./objectDelete');
 const objectDeleteTagging = require('./objectDeleteTagging');
 const objectGet = require('./objectGet');
 const objectGetACL = require('./objectGetACL');
+const objectGetAttributes = require('./objectGetAttributes.js');
 const objectGetLegalHold = require('./objectGetLegalHold');
 const objectGetRetention = require('./objectGetRetention');
 const objectGetTagging = require('./objectGetTagging');
@@ -471,6 +472,7 @@ const api = {
     objectDeleteTagging,
     objectGet,
     objectGetACL,
+    objectGetAttributes,
     objectGetLegalHold,
     objectGetRetention,
     objectGetTagging,

lib/api/apiUtils/object/parseAttributesHeader.js

@@ -0,0 +1,26 @@
+const { errorInstances } = require('arsenal');
+const { allowedObjectAttributes } = require('../../../../constants');
+
+function parseAttributesHeaders(headers) {
+  const raw = headers['x-amz-object-attributes'] || '';
+
+  const attributes = raw
+    .split(',')
+    .map(s => s.trim())
+    .filter(s => s !== '');
+
+  if (attributes.length === 0) {
+    return errorInstances.InvalidRequest.customizeDescription(
+      'The x-amz-object-attributes header specifying the attributes to be retrieved is either missing or empty',
+    );
+  }
+
+  const invalids = attributes.filter(s => !allowedObjectAttributes.has(s));
+  if (invalids.length > 0) {
+    return errorInstances.InvalidArgument.customizeDescription('Invalid attribute name specified.');
+  }
+
+  return attributes;
+}
+
+module.exports = parseAttributesHeaders;

lib/api/objectGetAttributes.js

@@ -0,0 +1,146 @@
+const { waterfall } = require('async');
+const xml2js = require('xml2js');
+const { errors } = require('arsenal');
+const { standardMetadataValidateBucketAndObj } = require('../metadata/metadataUtils');
+const collectCorsHeaders = require('../utilities/collectCorsHeaders');
+const parseAttributesHeaders = require('./apiUtils/object/parseAttributesHeader');
+const { decodeVersionId, getVersionIdResHeader } = require('./apiUtils/object/versioning');
+const { checkExpectedBucketOwner } = require('./apiUtils/authorization/bucketOwner');
+const { pushMetric } = require('../utapi/utilities');
+
+const OBJECT_GET_ATTRIBUTES = 'objectGetAttributes';
+
+/**
+ * buildXmlResponse - Build XML response for GetObjectAttributes
+ * @param {object} objMD - object metadata
+ * @param {array} attributes - requested attributes
+ * @returns {string} XML response
+ */
+function buildXmlResponse(objMD, attributes) {
+  const attrResp = {};
+
+  if (attributes.includes('ETag')) {
+    attrResp.ETag = objMD['content-md5'];
+  }
+
+  if (attributes.includes('Checksum')) {
+    attrResp.Checksum = {};
+  }
+
+  if (attributes.includes('ObjectParts')) {
+    attrResp.ObjectParts = {};
+  }
+
+  if (attributes.includes('StorageClass')) {
+    attrResp.StorageClass = objMD['x-amz-storage-class'];
+  }
+
+  if (attributes.includes('ObjectSize')) {
+    attrResp.ObjectSize = objMD['content-length'];
+  }
+
+  const builder = new xml2js.Builder();
+  return builder.buildObject({ GetObjectAttributesResponse: attrResp });
+}
+
+/**
+ * objectGetAttributes - Retrieves all metadata from an object without returning the object itself
+ * @param {AuthInfo} authInfo - Instance of AuthInfo class with requester's info
+ * @param {object} request - http request object
+ * @param {object} log - Werelogs logger
+ * @param {function} callback - callback to server
+ * @return {undefined}
+ */
+function objectGetAttributes(authInfo, request, log, callback) {
+  log.debug('processing request', { method: OBJECT_GET_ATTRIBUTES });
+  const { bucketName, objectKey, headers, actionImplicitDenies } = request;
+
+  const decodedVersionId = decodeVersionId(request.query);
+  if (decodedVersionId instanceof Error) {
+    log.trace('invalid versionId query', {
+      versionId: request.query.versionId,
+      error: decodedVersionId,
+    });
+    return callback(decodedVersionId);
+  }
+  const versionId = decodedVersionId;
+
+  const metadataValParams = {
+    authInfo,
+    bucketName,
+    objectKey,
+    versionId,
+    getDeleteMarker: true,
+    requestType: request.apiMethods || OBJECT_GET_ATTRIBUTES,
+    request,
+  };
+
+  let bucket = null;
+  let objMD = null;
+  let responseHeaders = null;
+  let xml = null;
+
+  return waterfall(
+    [
+      next =>
+        standardMetadataValidateBucketAndObj(metadataValParams, actionImplicitDenies, log, (err, b, o) => {
+          bucket = b;
+          objMD = o;
+          return next(err);
+        }),
+      next => checkExpectedBucketOwner(headers, bucket, log, next),
+      next => {
+        responseHeaders = collectCorsHeaders(headers.origin, request.method, bucket);
+        if (objMD) {
+          responseHeaders['x-amz-version-id'] = getVersionIdResHeader(bucket.getVersioningConfiguration(), objMD);
+          responseHeaders['Last-Modified'] = objMD['last-modified'] && new Date(objMD['last-modified']).toUTCString();
+        }
+
+        return next();
+      },
+      next => {
+        if (!objMD) {
+          const e = versionId ? errors.NoSuchVersion : errors.NoSuchKey;
+          return next(e);
+        }
+
+        if (objMD.isDeleteMarker) {
+          responseHeaders['x-amz-delete-marker'] = true;
+          return next(errors.MethodNotAllowed);
+        }
+
+        const attributes = parseAttributesHeaders(headers);
+        if (attributes instanceof Error) {
+          log.trace('invalid x-amz-object-attributes header', {
+            headers,
+            error: attributes,
+          });
+          return next(attributes);
+        }
+
+        xml = buildXmlResponse(objMD, attributes);
+        return next();
+      },
+    ],
+    err => {
+      if (err) {
+        log.debug('error processing request', {
+          error: err,
+          method: OBJECT_GET_ATTRIBUTES,
+        });
+        return callback(err, '', responseHeaders);
+      }
+
+      pushMetric(OBJECT_GET_ATTRIBUTES, log, {
+        authInfo,
+        bucket: bucketName,
+        keys: [objectKey],
+        versionId: objMD?.versionId,
+        location: objMD?.dataStoreName,
+      });
+      return callback(err, xml, responseHeaders);
+    },
+  );
+}
+
+module.exports = objectGetAttributes;