getDefaultTransport()

function getDefaultTransport(): Promise<DefaultTransport | undefined>;

The default dispatcher and its paired fetch, as a single value so the two are always read consistently. Resolves to undefined outside Node (browser/ edge), where callers use the global fetch with no dispatcher.

Use this when supplying a customFetch that should still honour the proxy environment variables (HTTP_PROXY, HTTPS_PROXY, NO_PROXY) and decode compressed responses the way the SDK does by default.

Both halves must be used together. dispatcher decompresses the response body itself, so a fetch from a different undici build will try to decode it a second time and the request fails mid-stream with terminated. A fetch of undefined means the runtime's global fetch is the correct partner for this dispatcher.

Returns

Promise<DefaultTransport | undefined>

Example

const transport = await getDefaultTransport()
const fetchImpl = transport?.fetch ?? fetch
const response = await fetchImpl(url, { ...options, dispatcher: transport?.dispatcher })