Return user metadata in GetObjectAttributes API

lib/api/apiUtils/authorization/prepareRequestContexts.js

@@ -261,6 +261,23 @@ function prepareRequestContexts(apiMethod, request, sourceBucket,
         if (requestedAttributes.filter(attr => attr != 'RestoreStatus').length > 0) {
             requestContexts.push(generateRequestContext('listObjectsV2OptionalAttributes'));
         }
+    } else if (apiMethodAfterVersionCheck === 'objectGetAttributes') {
+        if (request.headers['x-amz-version-id']) {
+            requestContexts.push(
+                generateRequestContext('objectGetVersion'),
+                generateRequestContext('objectGetVersionAttributes'),
+            );
+        } else {
+            requestContexts.push(
+                generateRequestContext('objectGet'),
+                generateRequestContext('objectGetAttributes'),
+            );
+        }
+
+        const attributes = request.headers['x-amz-object-attributes']?.split(',') ?? [];
+        if (attributes.some(attr => attr.trim().toLowerCase().startsWith('x-amz-meta-'))) {
+            requestContexts.push(generateRequestContext('objectGetAttributesCustom'));
+        }
     } else {
         const requestContext =
           generateRequestContext(apiMethodAfterVersionCheck);

lib/api/apiUtils/object/objectAttributes.js

@@ -0,0 +1,114 @@
+const { errorInstances } = require('arsenal');
+const { getPartCountFromMd5 } = require('./partInfo');
+
+/**
+ * Parse and validate attribute headers from a request.
+ * @param {object} headers - Request headers object
+ * @param {string} headerName - Name of the header to parse (e.g., 'x-amz-object-attributes')
+ * @param {Set<string>} supportedAttributes - Set of valid attribute names
+ * @returns {Set<string>} - set of requested attribute names
+ * @throws {arsenal.errors.InvalidRequest} When header is required but missing/empty
+ * @throws {arsenal.errors.InvalidArgument} When an invalid attribute name is specified
+ * @example
+ * // Input headers:
+ * { 'headerName': 'ETag, ObjectSize, x-amz-meta-custom' }
+ *
+ * // Parsed result:
+ * ['ETag', 'ObjectSize', 'x-amz-meta-custom']
+ */
+function parseAttributesHeaders(headers, headerName, supportedAttributes) {
+    const result = new Set();
+
+    const rawValue = headers[headerName];
+    if (rawValue === null || rawValue === undefined) {
+        return result;
+    }
+
+    for (const rawAttr of rawValue.split(',')) {
+        let attr = rawAttr.trim();
+
+        if (!supportedAttributes.has(attr)) {
+            attr = attr.toLowerCase();
+        }
+
+        if (!attr.startsWith('x-amz-meta-') && !supportedAttributes.has(attr)) {
+            throw errorInstances.InvalidArgument.customizeDescription('Invalid attribute name specified.');
+        }
+
+        result.add(attr);
+    }
+
+    return result;
+}
+
+/**
+ * buildAttributesXml - Builds XML reponse for requested object attributes
+ * @param {Object} objectMD - The internal metadata object for the file/object.
+ * @param {string} [objectMD.content-md5] - The MD5 hash used for the ETag.
+ * @param {string} [objectMD.x-amz-storage-class] - The storage tier of the object.
+ * @param {number} [objectMD.content-length] - The size of the object in bytes.
+ * @param {Object} [objectMD.restoreStatus] - Information regarding the restoration of archived objects.
+ * @param {boolean} [objectMD.restoreStatus.inProgress] - Whether a restore is currently active.
+ * @param {string} [objectMD.restoreStatus.expiryDate] - The date after which the restored copy expires.
+ * @param {Object.<string, any>} userMetadata - Key-value pairs of user-defined metadata.
+ * @param {string[]} requestedAttrs - A list of specific attributes to include in the output.
+ * Supports 'ETag', 'ObjectParts', 'StorageClass', 'ObjectSize',
+ * 'RestoreStatus', and 'x-amz-meta-*' for all user metadata.
+ * @param {string[]} xml - The string array acting as the output buffer/collector.
+ * @returns {void} - this function does not return a value, it mutates the `xml` param.
+ */
+function buildAttributesXml(objectMD, userMetadata, requestedAttrs, xml) {
+  const customAttributes = new Set();
+  for (const attribute of requestedAttrs) {
+    switch (attribute) {
+      case 'ETag':
+        xml.push(`<ETag>${objectMD['content-md5']}</ETag>`);
+        break;
+      case 'ObjectParts': {
+        const partCount = getPartCountFromMd5(objectMD);
+        if (partCount) {
+          xml.push(
+            '<ObjectParts>',
+            `<PartsCount>${partCount}</PartsCount>`,
+            '</ObjectParts>',
+          );
+        }
+        break;
+      }
+      case 'StorageClass':
+        xml.push(`<StorageClass>${objectMD['x-amz-storage-class']}</StorageClass>`);
+        break;
+      case 'ObjectSize':
+        xml.push(`<ObjectSize>${objectMD['content-length']}</ObjectSize>`);
+        break;
+      case 'RestoreStatus':
+        xml.push('<RestoreStatus>');
+        xml.push(`<IsRestoreInProgress>${!!objectMD.restoreStatus?.inProgress}</IsRestoreInProgress>`);
+
+        if (objectMD.restoreStatus?.expiryDate) {
+            xml.push(`<RestoreExpiryDate>${objectMD.restoreStatus?.expiryDate}</RestoreExpiryDate>`);
+        }
+
+        xml.push('</RestoreStatus>');
+        break;
+      case 'x-amz-meta-*':
+        for (const key of Object.keys(userMetadata)) {
+          customAttributes.add(key);
+        }
+        break;
+      default:
+        if (userMetadata[attribute]) {
+          customAttributes.add(attribute);
+        }
+    }
+  }
+
+  for (const key of customAttributes) {
+    xml.push(`<${key}>${userMetadata[key]}</${key}>`);
+  }
+}
+
+module.exports = {
+    parseAttributesHeaders,
+    buildAttributesXml,
+};

lib/api/bucketGet.js

@@ -10,6 +10,9 @@ const { pushMetric } = require('../utapi/utilities');
 const versionIdUtils = versioning.VersionID;
 const monitoring = require('../utilities/monitoringHandler');
 const { generateToken, decryptToken } = require('../api/apiUtils/object/continueToken');
+const { parseAttributesHeaders, buildAttributesXml } = require('./apiUtils/object/objectAttributes');
+
+const OPTIONAL_ATTRIBUTES = new Set(['RestoreStatus']);
 
 const xmlParamsToSkipUrlEncoding = new Set(['ContinuationToken', 'NextContinuationToken']);
 
@@ -150,7 +153,11 @@ function processVersions(bucketName, listParams, list) {
             `<ID>${v.Owner.ID}</ID>`,
             `<DisplayName>${v.Owner.DisplayName}</DisplayName>`,
             '</Owner>',
-            ...processOptionalAttributes(v, listParams.optionalAttributes),
+        );
+
+        buildAttributesXml(v, v.userMetadata, listParams.optionalAttributes, xml),
+
+        xml.push(
             `<StorageClass>${v.StorageClass}</StorageClass>`,
             v.IsDeleteMarker ? '</DeleteMarker>' : '</Version>'
         );
@@ -231,7 +238,7 @@ function processMasterVersions(bucketName, listParams, list) {
             );
         }
 
-        xml.push(...processOptionalAttributes(v, listParams.optionalAttributes));
+        buildAttributesXml(v, v.userMetadata, listParams.optionalAttributes, xml);
 
         return xml.push(
             `<StorageClass>${v.StorageClass}</StorageClass>`,
@@ -246,41 +253,6 @@ function processMasterVersions(bucketName, listParams, list) {
     return xml.join('');
 }
 
-function processOptionalAttributes(item, optionalAttributes) {
-    const xml = [];
-    const userMetadata = new Set();
-
-    for (const attribute of optionalAttributes) {
-        switch (attribute) {
-            case 'RestoreStatus':
-                xml.push('<RestoreStatus>');
-                xml.push(`<IsRestoreInProgress>${!!item.restoreStatus?.inProgress}</IsRestoreInProgress>`);
-
-                if (item.restoreStatus?.expiryDate) {
-                    xml.push(`<RestoreExpiryDate>${item.restoreStatus?.expiryDate}</RestoreExpiryDate>`);
-                }
-
-                xml.push('</RestoreStatus>');
-                break;
-            case 'x-amz-meta-*':
-                for (const key of Object.keys(item.userMetadata)) {
-                    userMetadata.add(key);
-                }
-                break;
-            default:
-                if (item.userMetadata?.[attribute]) {
-                    userMetadata.add(attribute);
-                }
-        }
-    }
-
-    for (const key of userMetadata) {
-        xml.push(`<${key}>${item.userMetadata[key]}</${key}>`);
-    }
-
-    return xml;
-}
-
 function handleResult(listParams, requestMaxKeys, encoding, authInfo, bucketName, list, log) {
     // eslint-disable-next-line no-param-reassign
     listParams.maxKeys = requestMaxKeys;
@@ -321,15 +293,11 @@ async function bucketGet(authInfo, request, log, callback) {
     const bucketName = request.bucketName;
     const v2 = params['list-type'];
 
-    const optionalAttributes =
-        request.headers['x-amz-optional-object-attributes']
-            ?.split(',')
-            .map(attr => attr.trim())
-            .map(attr => attr !== 'RestoreStatus' ? attr.toLowerCase() : attr)
-        ?? [];
-    if (optionalAttributes.some(attr => !attr.startsWith('x-amz-meta-') && attr != 'RestoreStatus')) {
-        throw errorInstances.InvalidArgument.customizeDescription('Invalid attribute name specified');
-    }
+    const optionalAttributes = parseAttributesHeaders(
+        request.headers,
+        'x-amz-optional-object-attributes',
+        OPTIONAL_ATTRIBUTES,
+    );
 
     if (v2 !== undefined && Number.parseInt(v2, 10) !== 2) {
         throw errorInstances.InvalidArgument.customizeDescription('Invalid List Type specified in Request');

lib/api/metadataSearch.js

@@ -20,7 +20,7 @@ function handleResult(listParams, requestMaxKeys, encoding, authInfo,
     // eslint-disable-next-line no-param-reassign
     listParams.encoding = encoding;
     // eslint-disable-next-line no-param-reassign
-    listParams.optionalAttributes = [];
+    listParams.optionalAttributes = new Set();
     let res;
     if (listParams.listingType === 'DelimiterVersions') {
         res = processVersions(bucketName, listParams, list);