default.md

Default retry policy

This is the retry policy used by default. It retries when there is a high chance that it might help.
This policy is based on the one in DataStax Java Driver. The behaviour is the same.

Examples

To use in Session:

# extern crate scylla;
# use scylla::Session;
# use std::error::Error;
# use std::sync::Arc;
# async fn check_only_compiles() -> Result<(), Box<dyn Error>> {
use scylla::{Session, SessionBuilder};
use scylla::execution::ExecutionProfile;
use scylla::execution::retries::DefaultRetryPolicy;

let handle = ExecutionProfile::builder()
    .retry_policy(Arc::new(DefaultRetryPolicy::new()))
    .build()
    .into_handle();

let session: Session = SessionBuilder::new()
    .known_node("127.0.0.1:9042")
    .default_execution_profile_handle(handle)
    .build()
    .await?;
# Ok(())
# }

To use in a simple query:

# extern crate scylla;
# use scylla::Session;
# use std::error::Error;
# use std::sync::Arc;
# async fn check_only_compiles(session: &Session) -> Result<(), Box<dyn Error>> {
use scylla::query::Query;
use scylla::execution::ExecutionProfile;
use scylla::execution::retries::DefaultRetryPolicy;

// Create a Query manually and set the retry policy
let mut my_query: Query = Query::new("INSERT INTO ks.tab (a) VALUES(?)");
my_query.set_retry_policy(Some(Arc::new(DefaultRetryPolicy::new())));

// You can also set retry policy in an execution profile
let handle = ExecutionProfile::builder()
    .retry_policy(Arc::new(DefaultRetryPolicy::new()))
    .build()
    .into_handle();
my_query.set_execution_profile_handle(Some(handle));

// Run the query using this retry policy
let to_insert: i32 = 12345;
session.query_unpaged(my_query, (to_insert,)).await?;
# Ok(())
# }

To use in a prepared query:

# extern crate scylla;
# use scylla::Session;
# use std::error::Error;
# use std::sync::Arc;
# async fn check_only_compiles(session: &Session) -> Result<(), Box<dyn Error>> {
use scylla::prepared_statement::PreparedStatement;
use scylla::execution::ExecutionProfile;
use scylla::execution::retries::DefaultRetryPolicy;

// Create PreparedStatement manually and set the retry policy
let mut prepared: PreparedStatement = session
    .prepare("INSERT INTO ks.tab (a) VALUES(?)")
    .await?;
prepared.set_retry_policy(Some(Arc::new(DefaultRetryPolicy::new())));

// You can also set retry policy in an execution profile
let handle = ExecutionProfile::builder()
    .retry_policy(Arc::new(DefaultRetryPolicy::new()))
    .build()
    .into_handle();
prepared.set_execution_profile_handle(Some(handle));

// Run the query using this retry policy
let to_insert: i32 = 12345;
session.execute_unpaged(&prepared, (to_insert,)).await?;
# Ok(())
# }