Struct persist_es::GenericQuery

pub struct GenericQuery<R, V, A> where
    R: ViewRepository<V, A>,
    V: View<A>,
    A: Aggregate,  { /* fields omitted */ }

A simple query and view repository. This is used both to act as a Query for processing events and to return materialized views.

Implementations

impl<R, V, A> GenericQuery<R, V, A> where
    R: ViewRepository<V, A>,
    V: View<A>,
    A: Aggregate, 

pub fn new(repo: R) -> Self

Creates a new GenericQuery using the provided ViewRepository.

let repo: MyRepo = ...
let query = GenericQuery::<MyRepo, MyView, MyAggregate>::new(repo);
let store = ...
let cqrs = CqrsFramework::new(store, vec![Box::new(query)]);

pub fn use_error_handler(
    &mut self,
    error_handler: Box<dyn Fn(PersistenceError) + Send + Sync + 'static>
)

Allows the user to apply a custom error handler to the query. Queries are infallible and should never cause errors, but programming errors or other technical problems might. Adding an error handler allows the user to choose whether to panic the application, log the error or otherwise register the issue.

This is not required for usage but without an error handler any error encountered by the query repository will simply be ignored, so it is strongly recommended.

An error handler that panics on any error.

query.use_error_handler(Box::new(|e|panic!("{}",e)));

pub async fn load(&self, query_instance_id: String) -> Option<V>

Loads and deserializes a view based on the provided view id. Use this method to load a materialized view when requested by a user.

This is an asynchronous method so don’t forget to await.

let view = query.load("customer-B24DA0".to_string()).await;

Trait Implementations

impl<R, V, A> Query<A> for GenericQuery<R, V, A> where
    R: ViewRepository<V, A>,
    V: View<A>,
    A: Aggregate, 

fn dispatch<'life0, 'life1, 'life2, 'async_trait>(
    &'life0 self,
    query_instance_id: &'life1 str,
    events: &'life2 [EventEnvelope<A>]
) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait>> where
    'life0: 'async_trait,
    'life1: 'async_trait,
    'life2: 'async_trait,
    Self: 'async_trait, 

Events will be dispatched here immediately after being committed for the downstream queries to be updated.