Ticketing Rust Library ​

Repository ​

Example ​

Basic Example ​

Create one broker at application startup and share it. wait=0 is one immediate attempt without a queue and the maximum wait is 255 seconds; lease is 1–250 seconds. The final minimum-work budget is required and may be zero. Clients round sub-second values up and reject out-of-range values or a budget greater than the normalized lease before sending; they never clamp.

use std::time::Duration;
use ticketing::TicketBroker;

let broker = TicketBroker::connect(["127.0.0.1:5225"]);
broker.wait_ready(Duration::from_secs(5)).await;

let ticket = broker.acquire(
    "key",
    Duration::from_secs(5),
    Duration::from_secs(30),
    Duration::from_secs(2),
).await?;
let token = ticket.token();
// In the same DB transaction: verify/update token high-water and perform the business write.
ticket.release().await?;

Automatic close/drop is a bounded best-effort release. Use the explicit release API when its result matters. The token must fence the protected database write in the same transaction.

Good to Know (Behavior) ​

• Once any request byte may have been sent, losing the definitive response yields Indeterminate. The client never automatically resends A with the same owner, and the caller must not enter the critical section.
• Cancellation before send is unsent; cancellation after possible send closes that session. If a grant token was parsed concurrently, the client attempts a bounded compensating exact-token release.
• M, every E, and malformed/oversized/unknown responses are session-fatal. Unresolved possible-send acquires become Indeterminate.
• B is a definitive capacity rejection and is returned immediately. There is no internal retry; the caller may later start a new acquire with a new owner and application-level backoff.
• Explicit and compensating release retry the exact token only within an absolute 5-second deadline from call/enqueue. R is success, N means already gone or not current, and no final response is an error—not assumed success.
• A Ticket is returned only with positive conservative time remaining and enough time for the required work budget. Work over 250 seconds is unsupported before send.
• The token is mandatory database fencing: in the same DB transaction, reject token <= stored_high_water, update the high-water mark, and perform the business write before commit/rollback and release.

Security Options (Token · TLS) ​

Every option is optional. token should match the server's client_tokens, and TLS has four modes: off / system trust store / a specified CA / skip verification (test only).

use ticketing::{TicketBroker, TlsMode};

let broker = TicketBroker::builder()
    .addrs(["10.0.0.1:5225", "10.0.0.2:5225", "10.0.0.3:5225"])
    .token("123")
    .tls(TlsMode::SystemRoots)
    // .tls(TlsMode::Ca("ca.crt".into()))
    // .tls(TlsMode::InsecureSkipVerify)
    .connect()?;

You can generate the server-side token, TLS, and cluster configuration on the Ticketing Server Deployment page.