Fetch a Transaction Request


def fetch_transaction(
    client: Client,
    account: PublicKey,
    link: str,
    commitment: Commitment | None = None,
    *,
    http_client: httpx.Client | None = None,
) -> Transaction | VersionedTransaction: ...

The merchant link must be an absolute HTTPS URL without credentials or a fragment. Solathon rejects redirects, oversized responses, malformed base64, unexpected signers, and invalid existing signatures. It never signs the returned transaction.


from solathon import Client, Keypair, Transaction
from solathon.solana_pay import fetch_transaction
 
wallet = Keypair.from_file("~/.config/solana/id.json")
 
with Client(endpoint) as client:
    transaction = fetch_transaction(
        client,
        account=wallet.public_key,
        link="https://merchant.example/solana-pay",
        commitment="confirmed",
    )
    message = (
        transaction.serialize_message()
        if isinstance(transaction, Transaction)
        else transaction.message.serialize()
    )
    transaction.add_signature(
        wallet.public_key,
        wallet.sign(message).signature,
    )
    signature = client.send_raw_transaction(transaction.serialize())

The default payment-request transport is separate from the RPC transport. RPC provider API keys, cookies, and authorization headers are therefore not sent to a cross-origin merchant. Pass a dedicated httpx.Client through http_client when you need merchant-specific headers.