Support upload latest file for GCS. (#3258)

* Support upload latest file for GCS.

* Cache time

lib/plugins/gcs/index.js

@@ -9,6 +9,26 @@ const { Storage } = require('@google-cloud/storage');
 const log = require('intel').getLogger('sitespeedio.plugin.gcs');
 const throwIfMissing = require('../../support/util').throwIfMissing;
 
+async function uploadLatestFiles(dir, gcsOptions, prefix) {
+  function ignoreDirs(file, stats) {
+    return stats.isDirectory();
+  }
+
+  const storage = new Storage({
+    projectId: gcsOptions.projectId,
+    keyFilename: gcsOptions.key
+  });
+  const bucket = storage.bucket(gcsOptions.bucketname);
+
+  const files = await readdir(dir, [ignoreDirs]);
+  const promises = [];
+
+  for (let file of files) {
+    promises.push(uploadFile(file, bucket, gcsOptions, prefix, dir, true));
+  }
+  return Promise.all(promises);
+}
+
 async function upload(dir, gcsOptions, prefix) {
   const files = await readdir(dir);
   const promises = [];
@@ -32,7 +52,14 @@ async function upload(dir, gcsOptions, prefix) {
   return Promise.all(promises);
 }
 
-async function uploadFile(file, bucket, gcsOptions, prefix, baseDir) {
+async function uploadFile(
+  file,
+  bucket,
+  gcsOptions,
+  prefix,
+  baseDir,
+  noCacheTime
+) {
   const subPath = path.relative(baseDir, file);
   const fileName = path.join(gcsOptions.path || prefix, subPath);
 
@@ -44,7 +71,7 @@ async function uploadFile(file, bucket, gcsOptions, prefix, baseDir) {
     gzip: !!gcsOptions.gzip,
     metadata: {
       metadata: {
-        cacheControl: 'public, max-age=31536000'
+        cacheControl: 'public, max-age=' + noCacheTime ? 0 : 31536000
       }
     }
   };
@@ -55,6 +82,7 @@ async function uploadFile(file, bucket, gcsOptions, prefix, baseDir) {
 module.exports = {
   open(context, options) {
     this.gcsOptions = options.gcs;
+    this.options = options;
     this.make = context.messageMaker('gcs').make;
     throwIfMissing(this.gcsOptions, ['bucketname'], 'gcs');
     this.storageManager = context.storageManager;
@@ -81,6 +109,12 @@ module.exports = {
           gcsOptions,
           this.storageManager.getStoragePrefix()
         );
+        if (this.options.copyLatestFilesToBase) {
+          const rootPath = path.resolve(baseDir, '..');
+          const dirsAsArray = rootPath.split(path.sep);
+          const rootName = dirsAsArray.slice(-1)[0];
+          await uploadLatestFiles(rootPath, gcsOptions, rootName);
+        }
         log.info('Finished upload to Google Cloud Storage');
         if (gcsOptions.public) {
           log.info(