To run from the x402 repo instead: clone coinbase/x402, then from the python examples root run the setup steps in the httpx README, copy .env-local to .env, and run the example.
This example loads your env, creates an x402 client, registers the EVM and/or SVM payment schemes, uses x402HttpxClient as an async context manager to make a GET request, and logs the response body and payment settlement from the response headers.
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"""x402 httpx client example - async HTTP with automatic payment handling."""import asyncioimport osimport sysfrom dotenv import load_dotenvfrom eth_account import Accountfrom x402 import x402Clientfrom x402.http import x402HTTPClientfrom x402.http.clients import x402HttpxClientfrom x402.mechanisms.evm import EthAccountSignerfrom x402.mechanisms.evm.exact.register import register_exact_evm_clientfrom x402.mechanisms.svm import KeypairSignerfrom x402.mechanisms.svm.exact.register import register_exact_svm_client# Load environment variablesload_dotenv()def validate_environment() -> tuple[str | None, str | None, str, str]: """Validate required environment variables. Returns: Tuple of (evm_private_key, svm_private_key, base_url, endpoint_path). Raises: SystemExit: If required environment variables are missing. """ evm_private_key = os.getenv("EVM_PRIVATE_KEY") svm_private_key = os.getenv("SVM_PRIVATE_KEY") base_url = os.getenv("RESOURCE_SERVER_URL") endpoint_path = os.getenv("ENDPOINT_PATH") missing = [] if not evm_private_key and not svm_private_key: missing.append("EVM_PRIVATE_KEY or SVM_PRIVATE_KEY") if not base_url: missing.append("RESOURCE_SERVER_URL") if not endpoint_path: missing.append("ENDPOINT_PATH") if missing: print(f"Error: Missing required environment variables: {', '.join(missing)}") print("Please copy .env-local to .env and fill in the values.") sys.exit(1) return evm_private_key, svm_private_key, base_url, endpoint_pathasync def main() -> None: """Main entry point demonstrating httpx with x402 payments.""" # Validate environment evm_private_key, svm_private_key, base_url, endpoint_path = validate_environment() # Create x402 client client = x402Client() # Register EVM payment scheme if private key provided if evm_private_key: account = Account.from_key(evm_private_key) register_exact_evm_client(client, EthAccountSigner(account)) print(f"Initialized EVM account: {account.address}") # Register SVM payment scheme if private key provided if svm_private_key: svm_signer = KeypairSigner.from_base58(svm_private_key) register_exact_svm_client(client, svm_signer) print(f"Initialized SVM account: {svm_signer.address}") # Create HTTP client helper for payment response extraction http_client = x402HTTPClient(client) # Build full URL url = f"{base_url}{endpoint_path}" print(f"Making request to: {url}\n") # Make request using async context manager async with x402HttpxClient(client) as http: response = await http.get(url) await response.aread() print(f"Response status: {response.status_code}") print(f"Response body: {response.text}") # Extract and print payment response if present if response.is_success: try: settle_response = http_client.get_payment_settle_response( lambda name: response.headers.get(name) ) print( f"\nPayment response: {settle_response.model_dump_json(indent=2)}" ) except ValueError: print("\nNo payment response header found") else: print(f"\nRequest failed (status: {response.status_code})")if __name__ == "__main__": asyncio.run(main())
You can test payments against a local server by running the fastapi example or the flask example from the x402 repository.Just set your environment variables to match your local server, install the dependencies, and run the examples.
You can also test your client against PayAI’s live Echo Merchant for free. You will receive a full refund of any tokens that you send, and PayAI will pay for the network fees.