Trait cqrs_es2::ICommandHandler

pub trait ICommandHandler<C: ICommand, E: IEvent> {
    fn handle(&self, command: C) -> Result<Vec<E>, Error>;
}

Command handlers are usually the aggregates. It consumes the command and emit all events resulting from this command.

Example

For illustration only:

use cqrs_es2::{
    example_impl::{
        AddressUpdated,
        CustomerCommand,
        CustomerEvent,
        EmailUpdated,
        NameAdded,
    },
    Error,
    ICommandHandler,
};

pub struct CustomerCommandHandler {};

impl ICommandHandler<CustomerCommand, CustomerEvent>
    for CustomerCommandHandler
{
    fn handle(
        &self,
        command: CustomerCommand,
    ) -> Result<Vec<CustomerEvent>, Error> {
        match command {
            CustomerCommand::AddCustomerName(payload) => {
                let payload = NameAdded {
                    changed_name: payload.changed_name,
                };

                Ok(vec![CustomerEvent::NameAdded(payload)])
            },
            CustomerCommand::UpdateEmail(payload) => {
                let payload = EmailUpdated {
                    new_email: payload.new_email,
                };

                Ok(vec![CustomerEvent::EmailUpdated(
                    payload,
                )])
            },
            CustomerCommand::AddAddress(payload) => {
                let payload = AddressUpdated {
                    new_address: payload.new_address,
                };

                Ok(vec![CustomerEvent::AddressUpdated(
                    payload,
                )])
            },
        }
    }
}

Required methods

fn handle(&self, command: C) -> Result<Vec<E>, Error>

handle inbound command and return a vector of events or an error

Implementors