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ApprovalHandler

agent_base::engine

Trait ApprovalHandler 

Source 
pub trait ApprovalHandler: Send + Sync {
    // Required method
    fn approve<'life0, 'async_trait>(
        &'life0 self,
        request: ApprovalRequest,
        cancel_token: CancellationToken,
    ) -> Pin<Box<dyn Future<Output = AgentResult<ApprovalDecision>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;
}
Expand description

Trait for handling tool approval requests.

§Cancellation Contract

Implementors MUST handle cancellation via the provided cancel_token. The token is cancelled when the user interrupts the agent (e.g., Ctrl+C).

  • Async handlers (channels, timers): race against cancel_token.cancelled() using tokio::select!
  • Blocking handlers (stdin, file IO): use tokio::task::spawn_blocking + tokio::select! to avoid blocking the tokio runtime

§Timeout

The caller (process_approval) wraps this method with a 300-second timeout. If the handler does not return within 300s, the approval is denied automatically.

§Example (blocking stdin)

ⓘ
async fn approve(&self, request: ApprovalRequest, cancel_token: CancellationToken) -> AgentResult<ApprovalDecision> {
    tokio::select! {
        _ = cancel_token.cancelled() => Err(AgentError::Cancelled),
        result = tokio::task::spawn_blocking(|| read_stdin()) => result?,
    }
}

Required Methods§

Source

fn approve<'life0, 'async_trait>( &'life0 self, request: ApprovalRequest, cancel_token: CancellationToken, ) -> Pin<Box<dyn Future<Output = AgentResult<ApprovalDecision>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait,

Dyn Compatibility§

This trait is dyn compatible.

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

Implementors§