1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165

//! # Intermediate Throw Event flow node
use crate::bpmn::schema::{
    Cast, EventDefinitionType, FlowNodeType, IntermediateThrowEvent as Element,
};
use crate::event::ProcessEvent;
use crate::flow_node::{self, Action, FlowNode, IncomingIndex};
use futures::stream::Stream;
use serde::{Deserialize, Serialize};
use std::pin::Pin;
use std::sync::Arc;
use std::task::{Context, Poll, Waker};
use tokio::sync::broadcast;

/// Intermediate Throw Event flow node
pub struct IntermediateThrowEvent {
    element: Arc<Element>,
    state: State,
    waker: Option<Waker>,
    event_broadcaster: Option<broadcast::Sender<ProcessEvent>>,
}

impl IntermediateThrowEvent {
    /// Creates new Intermediate Throw Event flow node
    pub fn new(element: Element) -> Self {
        Self {
            element: Arc::new(element),
            state: State::Ready,
            waker: None,
            event_broadcaster: None,
        }
    }
}

/// Node state
#[derive(Clone, Debug, Serialize, Deserialize)]
pub enum State {
    Ready,
    Complete,
    Done,
}

impl FlowNode for IntermediateThrowEvent {
    fn set_state(&mut self, state: flow_node::State) -> Result<(), flow_node::StateError> {
        match state {
            flow_node::State::IntermediateThrowEvent(state) => {
                self.state = state;
                Ok(())
            }
            _ => Err(flow_node::StateError::InvalidVariant),
        }
    }

    fn get_state(&mut self) -> flow_node::State {
        flow_node::State::IntermediateThrowEvent(self.state.clone())
    }

    fn element(&self) -> Box<dyn FlowNodeType> {
        Box::new(self.element.as_ref().clone())
    }

    fn incoming(&mut self, _index: IncomingIndex) {
        // Any incoming triggered is good enough to
        // complete IntermediateThrowEvent
        self.state = State::Complete;
        if let Some(waker) = self.waker.take() {
            waker.wake();
        }
    }

    fn set_process(&mut self, process: crate::process::Handle) {
        self.event_broadcaster.replace(process.event_broadcast());
    }
}

impl From<Element> for IntermediateThrowEvent {
    fn from(element: Element) -> Self {
        Self::new(element)
    }
}

impl Stream for IntermediateThrowEvent {
    type Item = Action;
    fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
        match self.state {
            State::Ready => {
                self.waker.replace(cx.waker().clone());
                Poll::Pending
            }
            State::Complete => {
                self.state = State::Done;
                if let Some(event_broadcaster) = self.event_broadcaster.as_ref() {
                    if self.element.event_definitions.is_empty() {
                        let _ = event_broadcaster.send(ProcessEvent::NoneEvent);
                    } else {
                        for event_definition in &self.element.event_definitions {
                            if let Some(definition) = Cast::<dyn EventDefinitionType>::cast(
                                event_definition.clone().into_inner().as_ref(),
                            ) {
                                use std::convert::TryFrom;
                                if let Ok(event) = ProcessEvent::try_from(definition) {
                                    let _ = event_broadcaster.send(event);
                                }
                            }
                        }
                    }
                }
                Poll::Ready(Some(Action::Flow(
                    (0..self.element.outgoings().len()).collect(),
                )))
            }
            State::Done => {
                self.waker.replace(cx.waker().clone());
                self.state = State::Ready;
                Poll::Pending
            }
        }
    }
}

#[cfg(test)]
mod tests {
    use crate::bpmn::parse;
    use crate::event::ProcessEvent;
    use crate::model;
    use crate::test::Mailbox;
    use bpxe_internal_macros as bpxe_im;

    #[bpxe_im::test]
    async fn throw_none_event() {
        let definitions = parse(include_str!("test_models/throw_none_event.bpmn")).unwrap();
        let model = model::Model::new(definitions).spawn().await;

        let handle = model.processes().await.unwrap().pop().unwrap();
        let mut mailbox = Mailbox::new(handle.event_receiver());

        assert!(handle.start().await.is_ok());

        assert!(
            mailbox
                .receive(|e| matches!(e, ProcessEvent::NoneEvent))
                .await
        );

        model.terminate().await;
    }

    #[bpxe_im::test]
    async fn throw_signal_event() {
        let definitions = parse(include_str!("test_models/throw_signal_event.bpmn")).unwrap();
        let model = model::Model::new(definitions).spawn().await;

        let handle = model.processes().await.unwrap().pop().unwrap();
        let mut mailbox = Mailbox::new(handle.event_receiver());

        assert!(handle.start().await.is_ok());

        assert!(
            mailbox
                .receive(|e| matches!(e, ProcessEvent::SignalEvent { signal_ref } if signal_ref.as_ref().unwrap() == "sig1"))
                .await
        );

        model.terminate().await;
    }
}