🎨 migrate buckgetGet to async/await

Issue: CLDSRV-823

Author: DarkIsDude

lib/api/bucketGet.js

@@ -8,14 +8,9 @@ const escapeForXml = s3middleware.escapeForXml;
 const { pushMetric } = require('../utapi/utilities');
 const versionIdUtils = versioning.VersionID;
 const monitoring = require('../utilities/monitoringHandler');
-const { generateToken, decryptToken }
-    = require('../api/apiUtils/object/continueToken');
+const { generateToken, decryptToken } = require('../api/apiUtils/object/continueToken');
 
-// do not url encode the continuation tokens
-const skipUrlEncoding = new Set([
-    'ContinuationToken',
-    'NextContinuationToken',
-]);
+const xmlParamsToSkipUrlEncoding = new Set(['ContinuationToken', 'NextContinuationToken',]);
 
 /* Sample XML response for GET bucket objects V2:
 <ListBucketResult xmlns="http://s3.amazonaws.com/doc/2006-03-01/">
@@ -122,17 +117,16 @@ function processVersions(bucketName, listParams, list) {
         { tag: 'IsTruncated', value: isTruncated },
     ];
 
-    const escapeXmlFn = listParams.encoding === 'url' ?
-        querystring.escape : escapeForXml;
+    const escapeXmlFn = listParams.encoding === 'url' ? querystring.escape : escapeForXml;
     xmlParams.forEach(p => {
         if (p.value) {
             const val = p.tag !== 'NextVersionIdMarker' || p.value === 'null' ?
-                p.value : versionIdUtils.encode(p.value);
+                p.value :
+                versionIdUtils.encode(p.value);
             xml.push(`<${p.tag}>${escapeXmlFn(val)}</${p.tag}>`);
         }
     });
-    let lastKey = listParams.keyMarker ?
-        escapeXmlFn(listParams.keyMarker) : undefined;
+    let lastKey = listParams.keyMarker ? escapeXmlFn(listParams.keyMarker) : undefined;
     list.Versions.forEach(item => {
         const v = item.value;
         const objectKey = escapeXmlFn(item.key);
@@ -143,7 +137,8 @@ function processVersions(bucketName, listParams, list) {
             `<Key>${objectKey}</Key>`,
             '<VersionId>',
             (v.IsNull || v.VersionId === undefined) ?
-                'null' : versionIdUtils.encode(v.VersionId),
+                'null'
+                : versionIdUtils.encode(v.VersionId),
             '</VersionId>',
             `<IsLatest>${isLatest}</IsLatest>`,
             `<LastModified>${v.LastModified}</LastModified>`,
@@ -182,31 +177,19 @@ function processMasterVersions(bucketName, listParams, list) {
     ];
 
     if (listParams.v2) {
-        xmlParams.push(
-            { tag: 'StartAfter', value: listParams.startAfter || '' });
-        xmlParams.push(
-            { tag: 'FetchOwner', value: `${listParams.fetchOwner}` });
-        xmlParams.push({
-            tag: 'ContinuationToken',
-            value: generateToken(listParams.continuationToken) || '',
-        });
-        xmlParams.push({
-            tag: 'NextContinuationToken',
-            value: generateToken(list.NextContinuationToken),
-        });
-        xmlParams.push({
-            tag: 'KeyCount',
-            value: list.Contents ? list.Contents.length : 0,
-        });
+        xmlParams.push({ tag: 'StartAfter', value: listParams.startAfter || '' });
+        xmlParams.push({ tag: 'FetchOwner', value: `${listParams.fetchOwner}` });
+        xmlParams.push({ tag: 'ContinuationToken', value: generateToken(listParams.continuationToken) || '', });
+        xmlParams.push({ tag: 'NextContinuationToken', value: generateToken(list.NextContinuationToken), });
+        xmlParams.push({ tag: 'KeyCount', value: list.Contents ? list.Contents.length : 0, });
     } else {
         xmlParams.push({ tag: 'Marker', value: listParams.marker || '' });
         xmlParams.push({ tag: 'NextMarker', value: list.NextMarker });
     }
 
-    const escapeXmlFn = listParams.encoding === 'url' ?
-        querystring.escape : escapeForXml;
+    const escapeXmlFn = listParams.encoding === 'url' ? querystring.escape : escapeForXml;
     xmlParams.forEach(p => {
-        if (p.value && skipUrlEncoding.has(p.tag)) {
+        if (p.value && xmlParamsToSkipUrlEncoding.has(p.tag)) {
             xml.push(`<${p.tag}>${p.value}</${p.tag}>`);
         } else if (p.value || p.tag === 'KeyCount' || p.tag === 'MaxKeys') {
             xml.push(`<${p.tag}>${escapeXmlFn(p.value)}</${p.tag}>`);
@@ -246,15 +229,14 @@ function processMasterVersions(bucketName, listParams, list) {
         );
     });
     list.CommonPrefixes.forEach(item => {
-        const val = escapeXmlFn(item);
-        xml.push(`<CommonPrefixes><Prefix>${val}</Prefix></CommonPrefixes>`);
+        xml.push(`<CommonPrefixes><Prefix>${escapeXmlFn(item)}</Prefix></CommonPrefixes>`);
     });
     xml.push('</ListBucketResult>');
+
     return xml.join('');
 }
 
-function handleResult(listParams, requestMaxKeys, encoding, authInfo,
-    bucketName, list, corsHeaders, log, callback) {
+function handleResult(listParams, requestMaxKeys, encoding, authInfo, bucketName, list, log) {
     // eslint-disable-next-line no-param-reassign
     listParams.maxKeys = requestMaxKeys;
     // eslint-disable-next-line no-param-reassign
@@ -267,9 +249,24 @@ function handleResult(listParams, requestMaxKeys, encoding, authInfo,
     }
     pushMetric('listBucket', log, { authInfo, bucket: bucketName });
     monitoring.promMetrics('GET', bucketName, '200', 'listBucket');
-    return callback(null, res, corsHeaders);
+    return res;
 }
 
+const validateBucket = (params, denials, log) => new Promise(resolve => {
+    standardMetadataValidateBucket(params, denials, log, (error, bucket) => {
+        resolve({ error, bucket });
+    });
+});
+
+const getObjectListing = (bucketName, listParams, log) => new Promise((resolve, reject) => {
+    services.getObjectListing(bucketName, listParams, log, (err, list) => {
+        if (err) {
+            return reject(err);
+        }
+        return resolve(list);
+    });
+});
+
 /**
  * bucketGet - Return list of objects in bucket, supports v1 & v2
  * @param  {AuthInfo} authInfo - Instance of AuthInfo class with
@@ -280,92 +277,86 @@ function handleResult(listParams, requestMaxKeys, encoding, authInfo,
  *  with either error code or xml response body
  * @return {undefined}
  */
-function bucketGet(authInfo, request, log, callback) {
-    const params = request.query;
-    const bucketName = request.bucketName;
-    const v2 = params['list-type'];
-    if (v2 !== undefined && Number.parseInt(v2, 10) !== 2) {
-        return callback(errorInstances.InvalidArgument.customizeDescription('Invalid ' +
-            'List Type specified in Request'));
-    }
-    if (v2) {
-        log.addDefaultFields({
-            action: 'ListObjectsV2',
-        });
-        if (request.serverAccessLog) {
-            // eslint-disable-next-line no-param-reassign
-            request.serverAccessLog.analyticsAction = 'ListObjectsV2';
+async function bucketGet(authInfo, request, log, callback) {
+    try {
+        const params = request.query;
+        const bucketName = request.bucketName;
+        const v2 = params['list-type'];
+
+        if (v2 !== undefined && Number.parseInt(v2, 10) !== 2) {
+            return callback(errorInstances.InvalidArgument.customizeDescription(
+                'Invalid List Type specified in Request'
+            ));
         }
-    } else if (params.versions !== undefined) {
-        log.addDefaultFields({
-            action: 'ListObjectVersions',
-        });
-        if (request.serverAccessLog) {
-            // eslint-disable-next-line no-param-reassign
-            request.serverAccessLog.analyticsAction = 'ListObjectVersions';
+
+        if (v2) {
+            log.addDefaultFields({ action: 'ListObjectsV2', });
+            if (request.serverAccessLog) {
+                // eslint-disable-next-line no-param-reassign
+                request.serverAccessLog.analyticsAction = 'ListObjectsV2';
+            }
+        } else if (params.versions !== undefined) {
+            log.addDefaultFields({ action: 'ListObjectVersions', });
+            if (request.serverAccessLog) {
+                // eslint-disable-next-line no-param-reassign
+                request.serverAccessLog.analyticsAction = 'ListObjectVersions';
+            }
         }
-    }
-    log.debug('processing request', { method: 'bucketGet' });
-    const encoding = params['encoding-type'];
-    if (encoding !== undefined && encoding !== 'url') {
-        monitoring.promMetrics(
-            'GET', bucketName, 400, 'listBucket');
-        return callback(errorInstances.InvalidArgument.customizeDescription('Invalid ' +
-            'Encoding Method specified in Request'));
-    }
-    const requestMaxKeys = params['max-keys'] ?
-        Number.parseInt(params['max-keys'], 10) : 1000;
-    if (Number.isNaN(requestMaxKeys) || requestMaxKeys < 0) {
-        monitoring.promMetrics(
-            'GET', bucketName, 400, 'listBucket');
-        return callback(errors.InvalidArgument);
-    }
-    // AWS only returns 1000 keys even if max keys are greater.
-    // Max keys stated in response xml can be greater than actual
-    // keys returned.
-    const actualMaxKeys = Math.min(constants.listingHardLimit, requestMaxKeys);
+        log.debug('processing request', { method: 'bucketGet' });
+        const encoding = params['encoding-type'];
+        if (encoding !== undefined && encoding !== 'url') {
+            monitoring.promMetrics('GET', bucketName, 400, 'listBucket');
+            return callback(errorInstances.InvalidArgument.customizeDescription(
+                'Invalid Encoding Method specified in Request'
+            ));
+        }
+        const requestMaxKeys = params['max-keys'] ? Number.parseInt(params['max-keys'], 10) : 1000;
+        if (Number.isNaN(requestMaxKeys) || requestMaxKeys < 0) {
+            monitoring.promMetrics('GET', bucketName, 400, 'listBucket');
+            return callback(errors.InvalidArgument);
+        }
+        const actualMaxKeys = Math.min(constants.listingHardLimit, requestMaxKeys);
 
-    const metadataValParams = {
-        authInfo,
-        bucketName,
-        requestType: request.apiMethods || 'bucketGet',
-        request,
-    };
-    const listParams = {
-        listingType: 'DelimiterMaster',
-        maxKeys: actualMaxKeys,
-        prefix: params.prefix,
-    };
+        const metadataValParams = {
+            authInfo,
+            bucketName,
+            requestType: request.apiMethods || 'bucketGet',
+            request,
+        };
+        const listParams = {
+            listingType: 'DelimiterMaster',
+            maxKeys: actualMaxKeys,
+            prefix: params.prefix,
+        };
 
-    if (params.delimiter) {
-        listParams.delimiter = params.delimiter;
-    }
+        if (params.delimiter) {
+            listParams.delimiter = params.delimiter;
+        }
 
-    if (v2) {
-        listParams.v2 = true;
-        listParams.startAfter = params['start-after'];
-        listParams.continuationToken =
-            decryptToken(params['continuation-token']);
-        listParams.fetchOwner = params['fetch-owner'] === 'true';
-    } else {
-        listParams.marker = params.marker;
-    }
+        if (v2) {
+            listParams.v2 = true;
+            listParams.startAfter = params['start-after'];
+            listParams.continuationToken = decryptToken(params['continuation-token']);
+            listParams.fetchOwner = params['fetch-owner'] === 'true';
+        } else {
+            listParams.marker = params.marker;
+        }
 
-    standardMetadataValidateBucket(metadataValParams, request.actionImplicitDenies, log, (err, bucket) => {
-        const corsHeaders = collectCorsHeaders(request.headers.origin,
-            request.method, bucket);
-        if (err) {
-            log.debug('error processing request', { error: err });
-            monitoring.promMetrics(
-                'GET', bucketName, err.code, 'listBucket');
-            return callback(err, null, corsHeaders);
+        const { error, bucket } = await validateBucket(metadataValParams, request.actionImplicitDenies, log);
+        const corsHeaders = collectCorsHeaders(request.headers.origin, request.method, bucket);
+
+        if (error) {
+            log.debug('error processing request', { error });
+            monitoring.promMetrics('GET', bucketName, error.code, 'listBucket');
+            return callback(error, null, corsHeaders);
         }
         if (params.versions !== undefined) {
             listParams.listingType = 'DelimiterVersions';
             delete listParams.marker;
             listParams.keyMarker = params['key-marker'];
             listParams.versionIdMarker = params['version-id-marker'] ?
-                versionIdUtils.decode(params['version-id-marker']) : undefined;
+                versionIdUtils.decode(params['version-id-marker']) :
+                undefined;
         }
         if (!requestMaxKeys) {
             const emptyList = {
@@ -374,26 +365,30 @@ function bucketGet(authInfo, request, log, callback) {
                 Versions: [],
                 IsTruncated: false,
             };
-            return handleResult(listParams, requestMaxKeys, encoding, authInfo,
-                bucketName, emptyList, corsHeaders, log, callback);
+            const res = handleResult(listParams, requestMaxKeys, encoding, authInfo, bucketName, emptyList, log);
+            return callback(null, res, corsHeaders);
         }
-        return services.getObjectListing(bucketName, listParams, log,
-        (err, list) => {
-            if (err) {
-                log.debug('error processing request', { error: err });
-                monitoring.promMetrics(
-                    'GET', bucketName, err.code, 'listBucket');
-                return callback(err, null, corsHeaders);
-            }
-            return handleResult(listParams, requestMaxKeys, encoding, authInfo,
-                bucketName, list, corsHeaders, log, callback);
-        });
-    });
-    return undefined;
+
+        let list;
+        try {
+            list = await getObjectListing(bucketName, listParams, log);
+        } catch (err) {
+            log.debug('error processing request', { error: err });
+            monitoring.promMetrics('GET', bucketName, err.code, 'listBucket');
+            return callback(err, null, corsHeaders);
+        }
+
+        const res = handleResult(listParams, requestMaxKeys, encoding, authInfo, bucketName, list, log);
+        return callback(null, res, corsHeaders);
+    } catch (err) {
+        log.error('unhandled error in bucketGet', { error: err });
+        return callback(errors.InternalError);
+    }
 }
 
 module.exports = {
     processVersions,
     processMasterVersions,
     bucketGet,
 };
+