Function executeCode

apps/sim/lib/execution/isolated-vm-worker.cjs:163–558

* Execute code in isolated-vm

(request, executionId)

 * Execute code in isolated-vm
 */
async function executeCode(request, executionId) {
  const { code, params, envVars, contextVariables, timeoutMs, requestId } = request
  const stdoutChunks = []
  let stdoutLength = 0
  let stdoutTruncated = false
  let isolate = null

  const appendStdout = (line) => {
    if (stdoutTruncated || !line) return

    const remaining = MAX_STDOUT_CHARS - stdoutLength
    if (remaining <= 0) {
      stdoutTruncated = true
      stdoutChunks.push('[stdout truncated]\n')
      return
    }

    if (line.length <= remaining) {
      stdoutChunks.push(line)
      stdoutLength += line.length
      return
    }

    stdoutChunks.push(line.slice(0, remaining))
    stdoutChunks.push('\n[stdout truncated]\n')
    stdoutLength = MAX_STDOUT_CHARS
    stdoutTruncated = true
  }

  let context = null
  let bootstrapScript = null
  let userScript = null
  let logCallback = null
  let errorCallback = null
  let fetchCallback = null
  let brokerCallback = null
  const externalCopies = []

  try {
    isolate = new ivm.Isolate({ memoryLimit: 128 })
    if (executionId !== undefined) activeIsolates.set(executionId, isolate)
    context = await isolate.createContext()
    const jail = context.global

    await jail.set('global', jail.derefInto())

    logCallback = new ivm.Callback((...args) => {
      const message = args.map((arg) => stringifyLogValue(arg)).join(' ')
      appendStdout(`${message}\n`)
    })
    await jail.set('__log', logCallback)

    errorCallback = new ivm.Callback((...args) => {
      const message = args.map((arg) => stringifyLogValue(arg)).join(' ')
      appendStdout(`ERROR: ${message}\n`)
    })
    await jail.set('__error', errorCallback)