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PushSender

a2a_protocol_server::push::sender

Trait PushSender 

Source 
pub trait PushSender:
    Send
    + Sync
    + 'static {
    // Required method
    fn send<'a>(
        &'a self,
        url: &'a str,
        event: &'a StreamResponse,
        config: &'a TaskPushNotificationConfig,
    ) -> Pin<Box<dyn Future<Output = A2aResult<()>> + Send + 'a>>;

    // Provided methods
    fn allows_private_urls(&self) -> bool { ... }
    fn max_delivery_duration(&self) -> Option<Duration> { ... }
}
Expand description

Trait for delivering push notifications to client webhooks.

Object-safe; used as Box<dyn PushSender>.

Required Methods§

Source

fn send<'a>( &'a self, url: &'a str, event: &'a StreamResponse, config: &'a TaskPushNotificationConfig, ) -> Pin<Box<dyn Future<Output = A2aResult<()>> + Send + 'a>>

Sends a streaming event to the client’s webhook URL.

§Errors

Returns an A2aError if delivery fails after all retries.

Provided Methods§

Source

fn allows_private_urls(&self) -> bool

Returns true if this sender allows webhook URLs targeting private/loopback addresses. Used by the handler to skip SSRF validation at push config creation time in testing environments.

Default: false (SSRF protection enabled).

Source

fn max_delivery_duration(&self) -> Option<Duration>

The longest a single send can take, if this sender can say — its whole retry schedule, not one attempt.

§Why this exists

Background delivery bounds every send with HandlerLimits::push_delivery_timeout, and a sender whose own schedule is longer than that bound never finishes it. At the shipped defaults the two contradict: HttpPushSender promises three attempts at 30s each with [1s, 2s] backoff — 93s — against a 5-second bound. Measured 2026-08-19 against a real socket: exactly one of the three attempts reaches the webhook, and the outer timeout fires at 5.001s. max_attempts and backoff are, at the defaults, configuration that cannot take effect.

Reporting a duration here lets the server tell “your webhook is slow” apart from “your two timeouts disagree” — see push_outcome::TIMEOUT_TRUNCATED.

Default: None, meaning “I cannot say”. A None sender is never reported as truncated, because nothing is known to have been cut short.

Dyn Compatibility§

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors§