POST /auth/register-pubkey

Binds a session public key to a merchant address. The session key is the signing identity for every authenticated call — see Authentication.

Request

POST /auth/register-pubkey

{
  "ownerAddress": "0xMerchant…",
  "publicKey": "0x04abc…",
  "signature": "0xWalletSig…"
}

Field	Type	Notes
ownerAddress	string	The merchant's wallet address.
publicKey	string	Uncompressed SEC1 secp256k1 pubkey (0x04…, 65 bytes). The public half of the session key your client will sign with.
signature	string	EIP-191 signature by ownerAddress over the raw publicKey string. Proves the merchant authorized this key.

The wallet signature ensures only the owner of ownerAddress can register a key against it. Use whatever signing UX your merchant wallet supports — MetaMask personal_sign, TronLink signMessageV2, or any eth_personalSign-compatible call.

Response

200 OK

{
  "registered": true,
  "ownerAddress": "0xMerchant…",
  "publicKey": "0x04abc…",
  "expiresAt": 1738169820
}

expiresAt is the unix timestamp when the registration stops being honored. Re-register before that window closes to keep the key live; re-registering the same pubkey is a refresh and preserves the per-key replay nonce.

Limits

A merchant may have multiple session keys registered at once (handy for rotating keys without downtime). Operators set a per-owner cap; once reached, registering a new key returns 409 Conflict until you deregister an existing one.

Example

JavaScript

import { Wallet } from 'ethers';

// 1. Generate the session key (the private half stays on your server / device).
const sessionKey = Wallet.createRandom();
const publicKey  = sessionKey.signingKey.publicKey;     // "0x04…" SEC1 hex

// 2. Have the merchant wallet sign the pubkey hex string.
const ownerWallet = /* MetaMask / TronLink / similar */;
const signature   = await ownerWallet.signMessage(publicKey);

// 3. Register.
await fetch('https://api.feemaker.io/auth/register-pubkey', {
  method: 'POST',
  headers: { 'content-type': 'application/json' },
  body: JSON.stringify({
    ownerAddress: ownerWallet.address,
    publicKey,
    signature,
  }),
});

Bash

# Pubkey & signature obtained out-of-band (e.g. from a wallet UI).
curl -X POST https://api.feemaker.io/auth/register-pubkey \
  -H "content-type: application/json" \
  -d '{
    "ownerAddress": "0xMerchant…",
    "publicKey":    "0x04abc…",
    "signature":    "0xWalletSig…"
  }'