Transport.from

Creates a custom server-side transport.

Usage

import { Challenge, Credential, Receipt } from 'mppx'
import { Transport } from 'mppx/server'
 
const http = Transport.from<Request, Response>({
  credentialHeaders: ['Authorization'],
 
  getCredential(request) {
    const header = request.headers.get('Authorization')
    if (!header) return null
    const payment = Credential.extractPaymentScheme(header)
    if (!payment) return null
    return Credential.deserialize(payment)
  },
 
  name: 'http',
 
  respondChallenge({ challenge, error }) {
    const headers: Record<string, string> = {
      'WWW-Authenticate': Challenge.serialize(challenge),
      'Cache-Control': 'no-store',
    }
 
    let body: string | null = null
    if (error) {
      headers['Content-Type'] = 'application/problem+json'
      body = JSON.stringify(error.toProblemDetails(challenge.id))
    }
 
    return new Response(body, { status: 402, headers })
  },
 
  respondReceipt({ receipt, response }) {
    const headers = new Headers(response.headers)
    headers.set('Payment-Receipt', Receipt.serialize(receipt))
    return new Response(response.body, {
      status: response.status,
      statusText: response.statusText,
      headers,
    })
  },
})

Return type

type ReturnType = Transport<Input, ChallengeOutput, ReceiptResponse, ReceiptOutput>

Parameters

bindCredential (optional)

• Type: (options: { challenge: Challenge; credential: Credential; input: Input }) => Credential | Promise<Credential>

Rebinds a transport-native Credential to the normalized route Challenge. Use this when the wire format doesn't carry an MPP Challenge directly.

captureRequest (optional)

• Type: (input: Input) => CapturedRequest | Promise<CapturedRequest>

Captures an immutable request snapshot for Challenge binding and later verification.

credentialHeaders (optional)

• Type: readonly string[]

HTTP header names from which this transport can read Credentials. Composed methods use this list to keep Credentials scoped to their matching transport.

getCredential

• Type: (input: Input) => Credential | null

Extracts Credential from the transport input. Returns null if no Credential was provided, or throws if malformed.

matchCredential (optional)

• Type: (options: { input: Input; request: Record<string, unknown> }) => boolean | Promise<boolean>

Returns whether a transport-native Credential targets one configured payment request. Use this when several configured offers share the same wire method and intent.

name

• Type: string

Transport name for identification.

respondChallenge

• Type: (options: { challenge: Challenge; error?: PaymentError; input: Input }) => ChallengeOutput | Promise<ChallengeOutput>

Creates a transport response for a payment Challenge.

respondReceipt

• Type: (options: { challengeId: string; credential: Credential; envelope?: VerifiedChallengeEnvelope; input: Input; receipt: Receipt; response: ReceiptResponse }) => ReceiptOutput

Attaches a Receipt to a successful response.

supportsStreamingReceipts (optional)

• Type: boolean

Marks transports whose Receipt wrapper accepts route-produced async iterables. Framework adapters use this to preserve streaming payment accounting.