✅ migrate tests to async/await

Issue: CLDSRV-878

Author: DarkIsDude

lib/routes/veeam/get.js

@@ -17,13 +17,13 @@ async function getVeeamFile(request, response, bucketMd, log) {
     }
 
     if ('tagging' in request.query) {
-        return respondWithData(request, response, log, bucketMd,
+        return await respondWithData(request, response, log, bucketMd,
             buildHeadXML('<Tagging><TagSet></TagSet></Tagging>'));
     }
 
     try {
         const result = await buildVeeamFileData(request, bucketMd, log, 'getVeeamFile');
-        return respondWithData(request, response, log, result.bucketData, result.xmlContent, result.modified);
+        return await respondWithData(request, response, log, result.bucketData, result.xmlContent, result.modified);
     } catch (err) {
         return responseXMLBody(err, null, response, log);
     }

lib/routes/veeam/list.js

@@ -150,7 +150,7 @@ async function listVeeamFiles(request, response, bucketMd, log) {
     });
 
     // When `versions` is present, listing should return a versioned list
-    return respondWithData(request, response, log, data,
+    return await respondWithData(request, response, log, data,
         buildXMLResponse(request, filesToBuild, 'versions' in request.query));
 }
 

lib/routes/veeam/utils.js

@@ -1,13 +1,16 @@
 const xml2js = require('xml2js');
 const { errors, errorInstances, jsutil } = require('arsenal');
-const { Readable } = require('stream');
+const { Readable, pipeline: streamPipeline } = require('stream');
+const { promisify } = require('util');
 const collectResponseHeaders = require('../../utilities/collectResponseHeaders');
 const collectCorsHeaders = require('../../utilities/collectCorsHeaders');
 const crypto = require('crypto');
 const { prepareStream } = require('arsenal/build/lib/s3middleware/prepareStream');
 const UtilizationService = require('../../utilization/instance');
 const metadata = require('../../metadata/wrapper');
 
+const pipeline = promisify(streamPipeline);
+
 /**
  * Decodes an URI and return the result.
  * Do the same decoding than in S3 server
@@ -109,23 +112,12 @@ function getResponseHeader(request, bucket, dataBuffer, lastModified, log) {
  * @param {BucketInfo} bucket - bucket info
  * @param {string} data - data to send
  * @param {date} [lastModified] - last modified date of the value
- * @returns {undefined} -
+ * @returns {Promise<void>} -
  */
-function respondWithData(request, response, log, bucket, data, lastModified) {
+async function respondWithData(request, response, log, bucket, data, lastModified) {
     const dataBuffer = Buffer.from(data);
     const responseMetaHeaders = getResponseHeader(request, bucket, dataBuffer, lastModified, log);
 
-    response.on('finish', () => {
-        let contentLength = 0;
-        if (responseMetaHeaders && responseMetaHeaders['Content-Length']) {
-            contentLength = responseMetaHeaders['Content-Length'];
-        }
-        log.end().addDefaultFields({ contentLength });
-        log.end().info('responded with streamed content', {
-            httpCode: response.statusCode,
-        });
-    });
-
     if (responseMetaHeaders && typeof responseMetaHeaders === 'object') {
         Object.keys(responseMetaHeaders).forEach(key => {
             if (responseMetaHeaders[key] !== undefined) {
@@ -143,13 +135,17 @@ function respondWithData(request, response, log, bucket, data, lastModified) {
     }
 
     response.writeHead(200);
-    const stream = Readable.from(dataBuffer);
-    stream.pipe(response);
-    stream.on('unpipe', () => {
-        response.end();
-    });
-    stream.on('error', () => {
-        response.end();
+    // Use a single-element array so the Buffer is sent as one chunk rather
+    // than being iterated byte-by-byte by Readable.from.
+    await pipeline(Readable.from([dataBuffer]), response);
+
+    let contentLength = 0;
+    if (responseMetaHeaders && responseMetaHeaders['Content-Length']) {
+        contentLength = responseMetaHeaders['Content-Length'];
+    }
+    log.end().addDefaultFields({ contentLength });
+    log.end().info('responded with streamed content', {
+        httpCode: response.statusCode,
     });
 }
 
@@ -308,7 +304,6 @@ async function buildVeeamFileData(request, bucketMd, log, name) {
 
 module.exports = {
     _decodeURI,
-    // callbackify keeps backward compatibility with put.js which still uses the callback form
     receiveData,
     respondWithData,
     getResponseHeader,