@lettrove/node

npm install @lettrove/node

Node.js 20 or newer, and edge runtimes (it uses only fetch and Web Crypto). It refuses to run in a browser.

import { Lettrove, LettroveApiError, verifyWebhook } from '@lettrove/node';

const lettrove = new Lettrove({ secretKey: process.env.LETTROVE_SECRET_KEY! });

new Lettrove(options)

Option	Type	Default
secretKey	string	required	lt_sk_test_… or lt_sk_live_…, from your environment. A publishable key, a cut-off key or a key with spaces is refused at once, with a message saying which.
timeoutMs	number	15000	How long to wait for an answer.
fetch	typeof fetch	the global	Your own fetch, for runtimes or tests that need one.

lettrove.environment is 'test' or 'live', read from the key.

tokens.create(input) → { token, expiresAt }

Input
user.id	Required. Your own id for the person (1–256 characters).
origin	Required. The page the editor opens on: the request's Origin header.
ttl	Optional. 60–900 seconds; default 900.

Minting tokens

designs.list(input) → { designs, nextCursor }

Input
user.id	Required.
limit	1–200, default 50.
cursor	nextCursor from the previous page.

Each design: { id, name, mode, revision, createdAt, updatedAt }, newest first.

designs.get(designId, { user }) → Design

The summary fields, plus doc: the design document.

designs.export(designId, input)

Input
user.id	Required.
merge	{ contact?, unsubscribeUrl?, preferencesUrl? } — Merge tags
text	{ links?, images?, preheader? } — how the plain text is written
format	'html' (default), 'pdf', 'png' or 'zip'
fullPage	For 'png': the whole design (default) or the first screen

With format 'html' or none, resolves with ExportedDesign: exportId, designId, revision, mode, html, chunks, text, subject, preheader, mergeTags, rendererVersion, bytes, warnings, design. With a file format, ExportedFile: exportId, designId, revision, mode, format, url, expiresAt, filename, bytes, warnings, design. The types follow format.

render(input) → RenderedDesign

Input
doc	Required. A design document you hold.
designId	Optional. Its id: a popup's handle and a form's event carry it.
merge, text	As for designs.export.

The fields of ExportedDesign without exportId, designId and revision: nothing is recorded.

users.erase(userId) → void

Erases one person and everything they made. Resolves when the erasure is under way. Erasure and privacy

verifyWebhook(rawBody, signature, secret, options?) → WebhookEvent

Argument
rawBody	The request body as a string, exactly as it arrived
signature	The Lettrove-Signature header
secret	The webhook's signing secret (whsec_…)
options.toleranceSeconds	How old a delivery may be; default 300

Throws LettroveApiError with code signature_invalid when the signature does not match, the body was changed, or the delivery is too old. Webhooks

LettroveApiError

Field
code	A stable error code
message	What happened
status	The HTTP status, or 0 when Lettrove could not be reached (network_error)
requestId	Quote it to support
retryAfter	Seconds to wait, when rate_limited
docsUrl	The code's row in Error codes, for your logs