Function retry

pub async fn retry<Fut, FutureFactoryFn, R, E>(
    address_list: &AddressList,
    settings: RequestSettings,
    future_factory_fn: FutureFactoryFn,
) -> ExecutionResult<R, E>
where
    Fut: Future<Output = ExecutionResult<R, E>>,
    FutureFactoryFn: FnMut(RequestSettings) -> Fut,
    E: CanRetry + Display + Debug,

Retry the provided closure.

This function is used to retry async code. It takes into account number of retries already executed by lower layers and stops retrying once the maximum number of retries is reached.

The settings should contain maximum number of retries that should be executed. In case of failure, total number of requests sent is expected to be at least settings.retries + 1 (initial request + retries configured in settings). The actual number of requests sent can be higher, as the lower layers can retry the request multiple times.

future_factory_fn should be a FnMut() closure that returns a future that should be retried. It takes RequestSettings as an argument and returns [ExecutionResult]. Retry mechanism can change RequestSettings between invocations of the future_factory_fn closure to limit the number of retries for lower layers.

Parameters

• address_list - list of addresses to be used for the requests.
• settings - global settings with any request-specific settings overrides applied.
• future_factory_fn - closure that returns a future that should be retried. It should take RequestSettings as an argument and return [ExecutionResult].

Returns

Returns future that resolves to [ExecutionResult].

Example

async fn retry_test_function(settings: RequestSettings) -> ExecutionResult<(), dash_sdk::Error> {
// do something
    Err(ExecutionError {
        inner: Error::StaleNode(StaleNodeError::Height{
            expected_height: 10,
            received_height: 3,
            tolerance_blocks: 1,
        }),
       retries: 0,
      address: None,
   })
}
#[tokio::main]
    async fn main() {
    let address_list = rs_dapi_client::AddressList::default();
    let global_settings = RequestSettings::default();
    dash_sdk::sync::retry(&address_list, global_settings, retry_test_function).await.expect_err("should fail");
}

Troubleshooting

Compiler error: no method named retry found for closure:

• ensure returned value is [ExecutionResult].,
• consider adding .await at the end of the closure.

See also

• [::backon] crate that is used by this function.