JavaScript runtime

The app functions you create for your app run within the Dynatrace JavaScript runtime. This page documents available JavaScript objects, WebAPIs, and packages of the SDK for TypeScript the runtime provides to write app functions.

SDK for TypeScript

The SDK for TypeScript can be used to access Dynatrace platform services and Dynatrace AppEngine functionality.

Standard built-in objects

The Dynatrace JavaScript runtime supports all standard JavaScript built-ins and the ECMAScript Internationalization API. For a list of available objects, visit the standard built-objects documentation on MDN (Mozilla Developer Network).

Web APIs

Web APIs are fundamental building blocks when writing web applications. Below is a list of all the APIs and interfaces (object types) available within the Dynatrace JavaScript runtime. To learn more about these APIs, visit Web API docs on MDN.

Caution

Deprecated properties of Web APIs might not be supported.

• AbortController
• AbortSignal
• atob
• Blob
• btoa
• ByteLengthQueuingStrategy
• clearInterval
• clearTimeout
• CompressionStream (currently only supported in deployed apps, not in local development)
• console
• CountQueuingStrategy
• Crypto
• crypto
• CryptoKey
• CustomEvent
• DecompressionStream (currently only supported in deployed apps, not in local development)
• DOMException
• ErrorEvent
• Event
• EventTarget
• fetch
• File
• FileReader
• FormData
• Headers
• Location
• location
• Navigator
• navigator
• Performance
• performance
• PerformanceEntry
• PerformanceMark
• PerformanceMeasure
• ProgressEvent
• PromiseRejectionEvent
• ReadableByteStreamController
• ReadableStream
• ReadableStreamBYOBReader
• ReadableStreamBYOBRequest
• ReadableStreamDefaultController
• ReadableStreamDefaultReader
• reportError
• Request
• Response
• setInterval
• setTimeout
• structuredClone
• SubtleCrypto
• TextDecoder
• TextDecoderStream
• TextEncoder
• TextEncoderStream
• TransformStream
• TransformStreamDefaultController
• URL
• URLPattern
• URLSearchParams
• Window
• window
• WritableStream
• WritableStreamDefaultController
• WritableStreamDefaultWriter

Node.js compatibility

The Dynatrace JavaScript runtime provides a compatibility layer for Node.js to improve compatibility with third-party npm packages.

Caution

Node.js compatibility is subject to limitations, and third-party packages that rely on operations such as TCP (Transmission Control Protocol)/UDP (User Datagram Protocol) socket or file system access aren't supported. Built-in modules in the compatibility layer might miss certain functionality from their Node.js counterparts.

Most functionality exposed in the Node.js compatibility layer is also available via Web APIs. We recommend using Web APIs such as fetch instead of Node.js modules like http where possible.

Available modules

The following built-in Node.js modules are available. Note that the list of limitations is non-exhaustive and subject to changes in the future.

Module	Description	Limitations
assert/strict, assert	Node.js assertions
buffer	Node.js-specific extensions to Uint8Array
console	Logging capabilities (e.g. console.log)
crypto	Cryptographic functionality such as hashing and encryption	Certain algorithms, custom certificates and Diffie-Hellman key exchanges aren't supported
events	Utilities around event emitters and listeners
http	HTTP server and client functionality over plain text	Creating an HTTP server isn't supported
https	HTTP server and client functionality over TLS (Transport Layer Security)	Creating an HTTP server isn't supported
path	Utilities for working with file and directory paths
perf_hooks	Performance measurement APIs	Some functionality isn't implemented: performance.timerify performance.eventLoopUtilization performance.monitorEventLoopDelay
querystring	Utilities for parsing and formatting URL query strings
stream, stream/consumers, stream/promises	APIs for streaming data
stream/web	An implementation of the WHATWG Streams Standard
string_decoder	APIs for decoding UTF-8 and UTF-16 data from streams	Unsupported encodings: ascii utf16le latin1
timers, timers/promises	API for scheduling functions to be called in the future
url	Utilities for URL resolution and parsing
util	Various utilities for application development
zlib	Compression and decompression utilities	Brotli compression isn't implemented

Stubbed modules

You can import the following modules to ensure compatibility with specific third-party packages, but all exposed functions throw errors when called.

Module	Description
process	Provides information about the current process
fs, fs/promises	File system operations