Adapter
Signer
An auth of the builder's own for a service: a function that is handed the finished request of a call and answers the request that is sent. A service names it with auth: { by: '<name>' }, for a provider that wants a signed request or a token made from a key file.
Interface
type Signer = (request: Request, o: { service: string; user?: string }) => Request | Promise<Request>It is made in signers of the makers in engine.ts, by the name the service gives, and declared in tentjs/connect, which tentjs/engine gives again. It runs last, after the lines of the service and the once-only key of a step, and once for each try, so a signature that holds a time is made anew each time. The request it is handed can be read more than once: request.clone().text() reads the body. user is the id of the user the call runs as, where it runs as one. An error in it fails the call with T0009, and the call is not tried again. A name that nobody made stops the app from opening (T7113). The service keeps its limits, its tries, its row of the log and its fake in tests.
Example
export const vault = service('vault', { url: 'https://vault.example.com', auth: { by: 'signed' }, calls: { read: get('/read', { input: {} }) } })
// engine.ts
import { createHmac } from 'node:crypto'
import type { Makers, Signer } from 'tentjs/engine'
export default {
signers: ({ secrets }) => ({
signed: (async (request) => {
const made = new Request(request)
const body = await request.clone().text()
made.headers.set('X-Signature', createHmac('sha256', secrets.VAULT_KEY.reveal()).update(body).digest('hex'))
return made
}) satisfies Signer,
}),
} satisfies Makers