Generate and parse messages

Generate

Pass an array of SIWE fields to SiweMessage and serialize it with prepareMessage().

use Iltumio\SiwePhp\SiweMessage;

$message = new SiweMessage([
    'domain' => 'example.com',
    'address' => '0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2',
    'statement' => 'Sign in to Example.',
    'uri' => 'https://example.com/login',
    'version' => '1',
    'chainId' => 1,
    'expirationTime' => gmdate('Y-m-d\TH:i:s\Z', time() + 300),
    'resources' => ['https://example.com/terms'],
]);

$text = $message->prepareMessage();
$nonce = $message->nonce;

When omitted, the nonce is generated using cryptographically secure randomness. issuedAt is populated on first serialization. Set an explicit chainId for the wallet's chain; serialization defaults an omitted chain ID to 1.

Dates must be valid RFC 3339 timestamps. The address must pass the library's EIP-55 validation. A custom nonce must contain at least eight alphanumeric characters. See the field reference.

Parse

$message = new SiweMessage($signedMessage);

$address = $message->address;
$chainId = $message->chainId;
$resources = $message->resources;

Parsing validates the input and preserves resources. Malformed dates, invalid nonces, duplicate fields, line breaks in fields and trailing data are rejected. Handle constructor failures before calling verify(); suppressExceptions only applies to verification.

Validate changes

Fields are public. After changing them, call validateMessage() to check their values. Serialization and verification also validate the message. Keep the stored challenge unchanged once the wallet has been asked to sign it.