n8n/packages/nodes-base/nodes/Function.node.ts
2020-04-13 16:51:04 +02:00

120 lines
3.2 KiB
TypeScript

import { IExecuteFunctions } from 'n8n-core';
import {
INodeExecutionData,
INodeType,
INodeTypeDescription,
} from 'n8n-workflow';
const { NodeVM } = require('vm2');
export class Function implements INodeType {
description: INodeTypeDescription = {
displayName: 'Function',
name: 'function',
icon: 'fa:code',
group: ['transform'],
version: 1,
description: 'Run custom function code which gets executed once and allows to add, remove, change and replace items.',
defaults: {
name: 'Function',
color: '#FF9922',
},
inputs: ['main'],
outputs: ['main'],
properties: [
{
displayName: 'Function',
name: 'functionCode',
typeOptions: {
alwaysOpenEditWindow: true,
editor: 'code',
rows: 10,
},
type: 'string',
default: 'items[0].json.myVariable = 1;\nreturn items;',
description: 'The JavaScript code to execute.',
noDataExpression: true,
},
],
};
async execute(this: IExecuteFunctions): Promise<INodeExecutionData[][]> {
// const item = this.getInputData();
let items = this.getInputData();
// Copy the items as they may get changed in the functions
items = JSON.parse(JSON.stringify(items));
// Define the global objects for the custom function
const sandbox = {
getNodeParameter: this.getNodeParameter,
getWorkflowStaticData: this.getWorkflowStaticData,
helpers: this.helpers,
items,
// To be able to access data of other items
$item: (index: number) => this.getWorkflowDataProxy(index),
};
// Make it possible to access data via $node, $parameter, ...
// By default use data from first item
Object.assign(sandbox, sandbox.$item(0));
const options = {
console: 'inherit',
sandbox,
require: {
external: false as boolean | { modules: string[] },
builtin: [] as string[],
}
};
if (process.env.NODE_FUNCTION_ALLOW_BUILTIN) {
options.require.builtin = process.env.NODE_FUNCTION_ALLOW_BUILTIN.split(',');
}
if (process.env.NODE_FUNCTION_ALLOW_EXTERNAL) {
options.require.external = { modules: process.env.NODE_FUNCTION_ALLOW_EXTERNAL.split(',') };
}
const vm = new NodeVM(options);
// Get the code to execute
const functionCode = this.getNodeParameter('functionCode', 0) as string;
try {
// Execute the function code
items = (await vm.run(`module.exports = async function() {${functionCode}}()`, __dirname));
} catch (e) {
return Promise.reject(e);
}
// Do very basic validation of the data
if (items === undefined) {
throw new Error('No data got returned. Always return an Array of items!');
}
if (!Array.isArray(items)) {
throw new Error('Always an Array of items has to be returned!');
}
for (const item of items) {
if (item.json === undefined) {
throw new Error('All returned items have to contain property named "json"!');
}
if (item.json === undefined) {
throw new Error('All returned items have to contain a property named "json"!');
}
if (typeof item.json !== 'object') {
throw new Error('The json-property has to be an object!');
}
if (item.binary !== undefined) {
if (Array.isArray(item.binary) || typeof item.binary !== 'object') {
throw new Error('The binary-property has to be an object!');
}
}
}
return this.prepareOutputData(items);
}
}