@theahaco/authline

Integrator SDK for one-signature trustline onboarding via an on-chain discovery router. The router discovers on-chain (via the SAC admin) whether the trustline also needs authorization, so the same single transaction shape works for every asset — open (USDC/EURC) or AUTH_REQUIRED. The onboard call returns an OnboardStatus (Authorized | TrustlineOnly); decode it with decodeOnboardStatus to know whether the line was also authorized, rather than treating tx success alone as full activation.

npm install @theahaco/authline

Discover an issuer's onboarder

import { discoverOnboarder } from "@theahaco/authline"

// Reads https://theaha.co/.well-known/stellar.toml -> [TRUSTLINE_ONBOARDER].
// Always pass `network` for any flow that builds a signed tx: the result is
// then reconciled against the pinned registry, so a spoofed stellar.toml whose
// ids differ from the curated values is rejected (throws) instead of trusted.
const config = await discoverOnboarder("theaha.co", { network: passphrase })
// { assetCode: "EURCV", assetIssuer: "G...", sac: "C...", router: "C...", authorizer: "C...", backends: [...] }

Without network, discoverOnboarder returns the issuer's unverified self-advertisement. StrKey validation proves the ids are well-formed, not that they are the right ids — reconcile against the registry before signing.

Build the one-signature transaction

import { buildOnboardTx, ROUTERS } from "@theahaco/authline"
import { Networks } from "@stellar/stellar-sdk"

// Standalone testnet illustration (the discover() example above is mainnet EURCV).
// The router id must be pinned per network; mainnet awaits the mainnet router deployment.
const xdr = await buildOnboardTx({
	rpcUrl: "https://soroban-testnet.stellar.org",
	networkPassphrase: Networks.TESTNET,
	holder: userPublicKey,
	config: { ...config, router: ROUTERS.TESTNET },
})
// Hand `xdr` to the wallet to sign (one signature), then submit via Stellar RPC.

React

import { ActivateButton } from "@theahaco/authline/react"
;<ActivateButton
	holder={address}
	config={config}
	rpcUrl={rpcUrl}
	networkPassphrase={passphrase}
	signTransaction={kit.signTransaction} // e.g. Stellar Wallets Kit
/>

Backends

• cap73-one-signature — funded holder signs once; on-chain onboard() wrapper composes CAP-73 trust() + authorize_trustline. (this SDK)
• cap33-sponsored — brand-new / under-funded account; classic sponsored-reserve transaction. Build it with buildSponsoredOnboardTx from this package (the sponsor pays the reserve). (this SDK)

Use selectBackend() to choose per holder.