API Reference

Deno Deploy Runtime helps you write web servers in TypeScript/JavaScript using the Web APIs. It’s different from Deno but aims to have similar APIs where applicable.

The following Web and Deno APIs are supported on Deno Deploy Runtime.

Web APIs

• console
• atob
• btoa
• Fetch API
  • fetch
  • Request
  • Response
  • URL
  • File
  • Blob
• TextEncoder
• TextDecoder
• TextEncoderStream
• TextDecoderStream
• Performance
• Web Crypto API
  • randomUUID()
  • getRandomValues()
  • SubtleCrypto
• WebSocket API
• Timers (setTimeout, clearTimeout, and setInterval)
• Streams API
  • ReadableStream
  • WritableStream
  • TransformStream
• URLPattern API
• Import Maps
  • Note: import maps are currently only available via deployctl or deployctl GitHub Action workflows.

Deno APIs

Note: only stable APIs of Deno are made available in Deploy.

• Deno.env - Interact with environment variables (secrets).
  • get(key: string): string | undefined - get the value of an environment variable.
  • toObject(): { [key: string]: string } - get all environment variables as an object.
• Deno.connect - Connect to TCP sockets.
• Deno.connectTls - Connect to TCP sockets using TLS.
• Deno.startTls - Start TLS handshake from an existing TCP connection.
• Deno.resolveDns - Make DNS queries
• File system API
  • Deno.cwd - Get the current working directory
  • Deno.readDir - Get directory listings
  • Deno.readFile - Read a file into memory
  • Deno.readTextFile - Read a text file into memory
  • Deno.open - Open a file for streaming reading
  • Deno.stat - Get file system entry information
  • Deno.lstat - Get file system entry information without following symlinks
  • Deno.realPath - Get the real path of a file after resolving symlinks
  • Deno.readLink - Get the target path for the given symlink

Future support

In the future, these APIs will also be added:

• Cache API
• UDP API:
  • Deno.connectDatagram for outbound UDP sockets
• Customizable fetch options using Deno.createHttpClient

Limitations

Just like the Deno CLI, we do not implement the __proto__ object field as specified in ECMA Script Annex B.