mneme 0.5.0

An event-sourcing library for Rust projects.
Documentation 
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use crate::error::Error;
use crate::event::Event;
use crate::event_store::{EventStreamId, EventStreamVersion};
use bytes::Bytes;
use std::marker::PhantomData;

impl eventstore::StreamName for EventStreamId {
    fn into_stream_name(self) -> Bytes {
        Bytes::from(self.0.to_string())
    }
}

pub struct EventStream<E: Event> {
    pub(crate) stream: eventstore::ReadStream,
    pub(crate) type_marker: PhantomData<E>,
}

impl<E: Event> EventStream<E> {
    pub async fn next(&mut self) -> Result<Option<(E, EventStreamVersion)>, Error> {
        match self.stream.next().await.or_else(|err| match err {
            eventstore::Error::ResourceNotFound => Ok(None),
            other => Err(other),
        })? {
            None => Ok(None),
            Some(resolved) => {
                let original = resolved.get_original_event();
                let stream_version = EventStreamVersion::new(original.revision);
                let event = original
                    .as_json::<E>()
                    .map_err(Error::EventDeserializationError)?;
                Ok(Some((event, stream_version)))
            }
        }
    }
}