add global.gc operation with expose-gc module

packages/app/package.json

@@ -11,7 +11,7 @@
     "clean": "npx -y shx rm -rf dist transpiled",
     "prebuild": "yarn cross-env NODE_ENV=production run-p clean resources:*",
     "postbuild": "npx -y shx mv transpiled/src dist && npx -y shx cp -r src/server/views dist/server/ && npx -y shx rm -rf transpiled",
-    "server": "yarn cross-env NODE_ENV=production node -r dotenv-flow/config --expose_gc dist/server/app.js",
+    "server": "yarn cross-env NODE_ENV=production node -r dotenv-flow/config dist/server/app.js",
     "server:ci": "yarn server --ci",
     "preserver": "yarn cross-env NODE_ENV=production yarn migrate",
     "migrate": "node -r dotenv-flow/config node_modules/.bin/migrate-mongo up",
@@ -19,7 +19,7 @@
     "dev": "run-p dev:client dev:server",
     "dev:client": "yarn cross-env NODE_ENV=development webpack --config config/webpack.dev.js --progress --watch",
     "dev:client:nowatch": "yarn cross-env NODE_ENV=development webpack --config config/webpack.dev.js",
-    "dev:server": "yarn cross-env NODE_ENV=development ts-node-dev --inspect --expose-gc -r tsconfig-paths/register -r dotenv-flow/config --transpile-only src/server/app.ts",
+    "dev:server": "yarn cross-env NODE_ENV=development ts-node-dev --inspect -r tsconfig-paths/register -r dotenv-flow/config --transpile-only src/server/app.ts",
     "predev:client": "yarn cross-env NODE_ENV=development run-p resources:*",
     "predev:server": "yarn cross-env NODE_ENV=development yarn dev:migrate:up",
     "dev:migrate-mongo": "yarn cross-env NODE_ENV=development yarn ts-node node_modules/.bin/migrate-mongo",

packages/app/src/server/service/import.js

@@ -1,23 +1,25 @@
+import gc from 'expose-gc/function';
+
 import loggerFactory from '~/utils/logger';
 
+
 const logger = loggerFactory('growi:services:ImportService'); // eslint-disable-line no-unused-vars
 const fs = require('fs');
 const path = require('path');
-
-const isIsoDate = require('is-iso-date');
-const parseISO = require('date-fns/parseISO');
-
 const { Writable, Transform } = require('stream');
+
 const JSONStream = require('JSONStream');
+const parseISO = require('date-fns/parseISO');
+const isIsoDate = require('is-iso-date');
+const mongoose = require('mongoose');
 const streamToPromise = require('stream-to-promise');
 const unzipper = require('unzipper');
 
-const mongoose = require('mongoose');
 
 const { ObjectId } = mongoose.Types;
 
-const { createBatchStream } = require('../util/batch-stream');
 const CollectionProgressingStatus = require('../models/vo/collection-progressing-status');
+const { createBatchStream } = require('../util/batch-stream');
 
 
 const BULK_IMPORT_SIZE = 100;
@@ -286,6 +288,15 @@ class ImportService {
 
           emitProgressEvent(collectionProgress, errors);
 
+          try {
+            // First aid to prevent unexplained memory leaks
+            logger.info('global.gc() invoked.');
+            gc();
+          }
+          catch (err) {
+            logger.error('fail garbage collection: ', err);
+          }
+
           callback();
         },
         final(callback) {

packages/app/src/server/service/search-delegator/elasticsearch.ts

@@ -3,6 +3,7 @@ import { URL } from 'url';
 
 import elasticsearch6 from '@elastic/elasticsearch6';
 import elasticsearch7 from '@elastic/elasticsearch7';
+import gc from 'expose-gc/function';
 import mongoose from 'mongoose';
 import streamToPromise from 'stream-to-promise';
 
@@ -593,7 +594,8 @@ class ElasticsearchDelegator implements SearchDelegator<Data, ESTermsKey, ESQuer
         if (invokeGarbageCollection) {
           try {
             // First aid to prevent unexplained memory leaks
-            global.gc();
+            logger.info('global.gc() invoked.');
+            gc();
           }
           catch (err) {
             logger.error('fail garbage collection: ', err);