async_flow/io/
port.rs

1// This is free and unencumbered software released into the public domain.
2
3use crate::PortDirection;
4
5use super::PortState;
6use dogma::{MaybeLabeled, MaybeNamed};
7
8/// The common interface for ports, whether for input or output.
9pub trait Port<T>: MaybeNamed + MaybeLabeled {
10    /// Closes this port without dropping it, returning immediately.
11    ///
12    /// If the port had an open connection, it will be disconnected.
13    /// If the port was already closed, no further action is taken.
14    /// There is no facility to reopen a port once it has been closed.
15    fn close(&mut self);
16
17    /// The dataflow direction of this port.
18    fn direction(&self) -> PortDirection;
19
20    /// The current state of this port.
21    fn state(&self) -> PortState;
22
23    /// Checks whether this port is an input port.
24    fn is_input(&self) -> bool {
25        self.direction().is_input()
26    }
27
28    /// Checks whether this port is an output port.
29    fn is_output(&self) -> bool {
30        self.direction().is_output()
31    }
32
33    /// Checks whether this port is currently closed.
34    fn is_closed(&self) -> bool {
35        self.state().is_closed()
36    }
37
38    /// Checks whether this port is currently open.
39    fn is_open(&self) -> bool {
40        self.state().is_open()
41    }
42
43    /// Checks whether this port is currently connected.
44    fn is_connected(&self) -> bool {
45        self.state().is_connected()
46    }
47
48    /// Returns the remaining buffer capacity of the connection.
49    fn capacity(&self) -> Option<usize> {
50        None // unknown
51    }
52
53    /// Returns the maximum buffer capacity of the connection.
54    fn max_capacity(&self) -> Option<usize> {
55        None // unknown
56    }
57}
58
59impl<T> core::fmt::Debug for &dyn Port<T> {
60    fn fmt(&self, f: &mut core::fmt::Formatter) -> core::fmt::Result {
61        f.debug_struct("Port")
62            .field("name", &self.name())
63            .field("state", &self.state())
64            .finish()
65    }
66}
async_flow/io/port.rs

async_flow/io/
port.rs
