From b70fc74e5c306691a89c5199bea374e01b9e9d35 Mon Sep 17 00:00:00 2001
From: harpagon210 <harpagon210@gmail.com>
Date: Tue, 6 Aug 2019 13:30:04 -0500
Subject: [PATCH] fixing vm allocation
---
libs/SmartContracts.js | 116 +++++++++++++++++++++++++++++------------
1 file changed, 82 insertions(+), 34 deletions(-)
diff --git a/libs/SmartContracts.js b/libs/SmartContracts.js
index 14ade11..dbde100 100644
--- a/libs/SmartContracts.js
+++ b/libs/SmartContracts.js
@@ -12,6 +12,9 @@ const DB_PLUGIN_ACTIONS = require('../plugins/Database.constants').PLUGIN_ACTION
const RESERVED_CONTRACT_NAMES = ['contract', 'blockProduction', 'null'];
const RESERVED_ACTIONS = ['createSSC'];
+const JSVMs = [];
+const MAXJSVMs = 5;
+
class SmartContracts {
// deploy the smart contract to the blockchain and initialize the database if needed
static async deploySmartContract(
@@ -54,31 +57,34 @@ class SmartContracts {
// this code template is used to manage the code of the smart contract
// this way we keep control of what can be executed in a smart contract
let codeTemplate = `
- RegExp.prototype.constructor = function () { };
- RegExp.prototype.exec = function () { };
- RegExp.prototype.test = function () { };
-
- let actions = {};
-
- ###ACTIONS###
-
- const execute = async function () {
- try {
- if (api.action && typeof api.action === 'string' && typeof actions[api.action] === 'function') {
- if (api.action !== 'createSSC') {
- actions.createSSC = null;
+ function wrapper () {
+ RegExp.prototype.constructor = function () { };
+ RegExp.prototype.exec = function () { };
+ RegExp.prototype.test = function () { };
+
+ let actions = {};
+
+ ###ACTIONS###
+
+ const execute = async function () {
+ try {
+ if (api.action && typeof api.action === 'string' && typeof actions[api.action] === 'function') {
+ if (api.action !== 'createSSC') {
+ actions.createSSC = null;
+ }
+ await actions[api.action](api.payload);
+ done(null);
+ } else {
+ done('invalid action');
}
- await actions[api.action](api.payload);
- done(null);
- } else {
- done('invalid action');
+ } catch (error) {
+ done(error);
}
- } catch (error) {
- done(error);
}
- }
- execute();
+ execute();
+ }
+ wrapper();
`;
// the code of the smart contarct comes as a Base64 encoded string
@@ -374,25 +380,67 @@ class SmartContracts {
}
}
+ static getJSVM(jsVMTimeout) {
+ let vm = null;
+
+ vm = JSVMs.find(v => v.inUse === false);
+
+ if (vm === undefined) {
+ if (JSVMs.length < MAXJSVMs) {
+ vm = {
+ vm: new VM({
+ timeout: jsVMTimeout,
+ sandbox: {
+ },
+ }),
+ inUse: true,
+ };
+ JSVMs.push(vm);
+ }
+ }
+
+ if (vm === undefined) {
+ vm = null;
+ } else {
+ // eslint-disable-next-line no-underscore-dangle
+ Object.keys(vm.vm._context).filter(key => key !== 'VMError' && key !== 'Buffer' && key !== 'api').forEach((key) => {
+ // eslint-disable-next-line no-underscore-dangle
+ delete vm.vm._context[key];
+ });
+ // eslint-disable-next-line no-underscore-dangle
+ vm.vm._context.api = {};
+ vm.inUse = true;
+ }
+
+ return vm;
+ }
+
// run the contractCode in a VM with the vmState as a state for the VM
static runContractCode(vmState, contractCode, jsVMTimeout) {
return new Promise((resolve) => {
+ const vm = SmartContracts.getJSVM(jsVMTimeout);
try {
- // console.log('vmState', vmState)
// run the code in the VM
- const vm = new VM({
- timeout: jsVMTimeout,
- sandbox: {
- ...vmState,
- done: (error) => {
- // console.log('error', error);
- resolve(error);
- },
- },
- });
-
- vm.run(contractCode);
+ if (vm !== null) {
+ // eslint-disable-next-line no-underscore-dangle
+ Object.keys(vmState.api).forEach((key) => {
+ // eslint-disable-next-line no-underscore-dangle
+ vm.vm._context.api[key] = vmState.api[key];
+ });
+ // eslint-disable-next-line no-underscore-dangle
+ vm.vm._context.done = (error) => {
+ // console.log('error', error);
+ vm.inUse = false;
+ resolve(error);
+ };
+
+ vm.vm.run(contractCode);
+ } else {
+ resolve('no JS VM available');
+ }
} catch (err) {
+ // console.log('error', err);
+ vm.inUse = false;
resolve(err);
}
});