Reduced memory footprint by dereferencing bootCode

CHANGELOG.yaml

@@ -1,3 +1,6 @@
+unreleased:
+  fixed bugs:
+    - GH-1037 Reduced memory footprint by dereferencing bootCode
 5.1.1:
   date: 2024-08-01
   fixed bugs:

lib/index.js

@@ -1,5 +1,4 @@
 const _ = require('lodash'),
-    bootcode = require('./bootcode'),
     PostmanSandbox = require('./postman-sandbox'),
     PostmanSandboxFleet = require('./postman-sandbox-fleet');
 
@@ -17,14 +16,7 @@ module.exports = {
         }
 
         options = _.clone(options);
-        bootcode((err, code) => {
-            if (err) { return callback(err); }
-            if (!code) { return callback(new Error('sandbox: bootcode missing!')); }
-
-            options.bootCode = code; // assign the code in options
-
-            new PostmanSandbox().initialize({}, options, callback);
-        });
+        new PostmanSandbox().initialize({}, options, callback);
     },
 
     /**
@@ -60,20 +52,13 @@ module.exports = {
 
         connectOptions = _.clone(connectOptions);
 
-        bootcode((err, code) => {
-            if (err) { return callback(err); }
-            if (!code) { return callback(new Error('sandbox: bootcode missing!')); }
-
-            connectOptions.bootCode = code;
+        try {
+            const sandboxFleet = new PostmanSandboxFleet(registry, initOptions, connectOptions);
 
-            try {
-                const sandboxFleet = new PostmanSandboxFleet(registry, initOptions, connectOptions);
-
-                return callback(null, sandboxFleet);
-            }
-            catch (err) {
-                return callback(err);
-            }
-        });
+            return callback(null, sandboxFleet);
+        }
+        catch (err) {
+            return callback(err);
+        }
     }
 };

lib/postman-sandbox.js

@@ -3,12 +3,23 @@ const _ = require('lodash'),
     UniversalVM = require('uvm'),
     PostmanEvent = require('postman-collection').Event,
     teleportJS = require('teleport-javascript'),
+    bootcode = require('./bootcode'),
 
     TO_WAIT_BUFFER = 500, // time to wait for sandbox to declare timeout
     CONSOLE_EVENT_NAME = 'execution.console',
     EXECUTION_TIMEOUT_ERROR_MESSAGE = 'sandbox not responding',
     BRIDGE_DISCONNECTING_ERROR_MESSAGE = 'sandbox: execution interrupted, bridge disconnecting.';
 
+
+function getBootCode (callback) {
+    bootcode((err, code) => {
+        if (err) { return callback(err); }
+        if (!code) { return callback(new Error('sandbox: bootcode missing!')); }
+
+        callback(null, code);
+    });
+}
+
 class PostmanSandbox extends UniversalVM {
     constructor () {
         super();
@@ -28,27 +39,35 @@ class PostmanSandbox extends UniversalVM {
         // set the dispatch timeout of UVM based on what is set in options unless original options sends the same
         _.isFinite(this.connectOptions.timeout) && (this.executionTimeout = this.connectOptions.timeout);
 
-        super.connect(this.connectOptions, (err, context) => {
+        getBootCode((err, bootCode) => {
             if (err) { return callback(err); }
 
-            this.once('initialize', (err) => {
-                this.isReady = true;
-                this.hasTimedOut = false;
+            this.connectOptions.bootCode = bootCode;
+
+            super.connect(this.connectOptions, (err, context) => {
+                delete this.connectOptions.bootCode;
 
-                this.on(CONSOLE_EVENT_NAME, (cursor, level, args) => {
-                    if (this.connectOptions.serializeLogs) {
-                        return this.emit('console', cursor, level, args);
-                    }
+                if (err) { return callback(err); }
 
-                    this.emit('console', cursor, level, ...teleportJS.parse(args));
+                this.once('initialize', (err) => {
+                    this.isReady = true;
+                    this.hasTimedOut = false;
+
+                    this.on(CONSOLE_EVENT_NAME, (cursor, level, args) => {
+                        if (this.connectOptions.serializeLogs) {
+                            return this.emit('console', cursor, level, args);
+                        }
+
+                        this.emit('console', cursor, level, ...teleportJS.parse(args));
+                    });
+
+                    // eslint-disable-next-line n/callback-return
+                    callback(err, context);
+                    context = null;
                 });
 
-                // eslint-disable-next-line n/callback-return
-                callback(err, context);
-                context = null;
+                this.dispatch('initialize', this.initOptions);
             });
-
-            this.dispatch('initialize', this.initOptions);
         });
     }
 

test/unit/sandbox-sanity.test.js

@@ -292,4 +292,15 @@ describe('sandbox', function () {
             });
         });
     });
+
+    it('should not hold reference to bootCode after initialization', function (done) {
+        // TODO: Add a memory footprint test to ensure bootCode is not retained elsewhere
+        Sandbox.createContext({ debug: true }, function (err, ctx) {
+            if (err) { return done(err); }
+            ctx.on('error', done);
+
+            expect(ctx.connectOptions.bootCode).to.be.undefined;
+            done();
+        });
+    });
 });