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lapin/
channel_status.rs

1use crate::{
2    Error, ErrorKind, Result,
3    channel_receiver_state::{ChannelReceiverStates, DeliveryCause},
4    channel_recovery_context::ChannelRecoveryContext,
5    internal_rpc::InternalRPCHandle,
6    killswitch::KillSwitch,
7    notifier::Notifier,
8    topology::ChannelDefinition,
9    types::{ChannelId, Identifier, PayloadSize},
10};
11use std::{
12    fmt,
13    sync::{Arc, RwLock, RwLockReadGuard, RwLockWriteGuard},
14};
15use tracing::trace;
16
17#[derive(Clone)]
18pub struct ChannelStatus(Arc<RwLock<Inner>>);
19
20impl ChannelStatus {
21    pub(crate) fn new(id: ChannelId, internal_rpc: InternalRPCHandle) -> Self {
22        Self(Arc::new(RwLock::new(Inner::new(id, internal_rpc))))
23    }
24
25    pub fn initializing(&self) -> bool {
26        [ChannelState::Initial, ChannelState::Reconnecting].contains(&self.read().state)
27    }
28
29    pub fn closing(&self) -> bool {
30        [ChannelState::Closing, ChannelState::Reconnecting].contains(&self.read().state)
31    }
32
33    pub fn connected(&self) -> bool {
34        self.read().state == ChannelState::Connected
35    }
36
37    pub fn reconnecting(&self) -> bool {
38        self.read().state == ChannelState::Reconnecting
39    }
40
41    pub(crate) fn connected_or_recovering(&self) -> bool {
42        [ChannelState::Connected, ChannelState::Reconnecting].contains(&self.read().state)
43    }
44
45    pub(crate) fn update_recovery_context<R, F: Fn(&mut ChannelRecoveryContext) -> R>(
46        &self,
47        apply: F,
48    ) -> Option<R> {
49        Some(apply(self.write().recovery_context.as_mut()?))
50    }
51
52    pub(crate) fn finalize_connection(&self) {
53        self.write().finalize_connection();
54    }
55
56    pub(crate) fn can_receive_messages(&self) -> bool {
57        [
58            ChannelState::Closing,
59            ChannelState::Connected,
60            ChannelState::Reconnecting,
61        ]
62        .contains(&self.read().state)
63    }
64
65    pub fn confirm(&self) -> bool {
66        self.read().confirm
67    }
68
69    pub(crate) fn set_confirm(&self) {
70        let mut inner = self.write();
71        inner.confirm = true;
72        trace!("Publisher confirms activated");
73        inner.finalize_connection();
74    }
75
76    pub(crate) fn set_state(&self, state: ChannelState) {
77        self.write().state = state;
78    }
79
80    pub(crate) fn state_error(&self, context: &'static str) -> Error {
81        let inner = self.read();
82        let error = Error::from(ErrorKind::InvalidChannelState(inner.state, context));
83        if inner.state == ChannelState::Reconnecting {
84            return error.with_notifier(inner.notifier());
85        }
86        error
87    }
88
89    pub(crate) fn set_reconnecting(&self, error: Error, topology: ChannelDefinition) -> Error {
90        self.write().set_reconnecting(error, topology)
91    }
92
93    pub(crate) fn auto_close(&self, id: ChannelId) -> bool {
94        id != 0 && self.connected()
95    }
96
97    #[cfg(test)]
98    pub(crate) fn receiver_state(&self) -> crate::channel_receiver_state::ChannelReceiverState {
99        self.write().receiver_state.receiver_state()
100    }
101
102    pub(crate) fn set_will_receive(
103        &self,
104        class_id: Identifier,
105        delivery_cause: DeliveryCause,
106    ) -> KillSwitch {
107        let mut inner = self.write();
108        inner
109            .receiver_state
110            .set_will_receive(class_id, delivery_cause);
111        inner.killswitch.clone()
112    }
113
114    pub(crate) fn set_content_length<
115        Handler: FnOnce(&DeliveryCause, bool),
116        OnInvalidClass: FnOnce(String) -> Result<()>,
117        OnError: FnOnce(String) -> Result<()>,
118    >(
119        &self,
120        channel_id: ChannelId,
121        class_id: Identifier,
122        length: PayloadSize,
123        handler: Handler,
124        invalid_class_hanlder: OnInvalidClass,
125        error_handler: OnError,
126    ) -> Result<()> {
127        let mut inner = self.write();
128        let confirm_mode = inner.confirm;
129        inner.receiver_state.set_content_length(
130            channel_id,
131            class_id,
132            length,
133            handler,
134            invalid_class_hanlder,
135            error_handler,
136            confirm_mode,
137        )
138    }
139
140    pub(crate) fn receive<
141        Handler: FnOnce(&DeliveryCause, PayloadSize, bool),
142        OnError: FnOnce(String) -> Result<()>,
143    >(
144        &self,
145        channel_id: ChannelId,
146        length: PayloadSize,
147        handler: Handler,
148        error_handler: OnError,
149    ) -> Result<()> {
150        let mut inner = self.write();
151        let confirm_mode = inner.confirm;
152        inner
153            .receiver_state
154            .receive(channel_id, length, handler, error_handler, confirm_mode)
155    }
156
157    pub(crate) fn set_send_flow(&self, flow: bool) {
158        self.write().send_flow = flow;
159    }
160
161    pub(crate) fn flow(&self) -> bool {
162        self.read().send_flow
163    }
164
165    fn read(&self) -> RwLockReadGuard<'_, Inner> {
166        self.0.read().unwrap_or_else(|e| e.into_inner())
167    }
168
169    fn write(&self) -> RwLockWriteGuard<'_, Inner> {
170        self.0.write().unwrap_or_else(|e| e.into_inner())
171    }
172}
173
174#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
175pub enum ChannelState {
176    #[default]
177    Initial,
178    Reconnecting,
179    Connected,
180    Closing,
181    Closed,
182    Error,
183}
184
185impl fmt::Debug for ChannelStatus {
186    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
187        let mut debug = f.debug_struct("ChannelStatus");
188        if let Ok(inner) = self.0.try_read() {
189            debug
190                .field("state", &inner.state)
191                .field("receiver_state", &inner.receiver_state)
192                .field("confirm", &inner.confirm)
193                .field("send_flow", &inner.send_flow);
194        }
195        debug.finish()
196    }
197}
198
199struct Inner {
200    id: ChannelId,
201    confirm: bool,
202    send_flow: bool,
203    state: ChannelState,
204    receiver_state: ChannelReceiverStates,
205    recovery_context: Option<ChannelRecoveryContext>,
206    killswitch: KillSwitch,
207    internal_rpc: InternalRPCHandle,
208}
209
210impl Inner {
211    fn new(id: ChannelId, internal_rpc: InternalRPCHandle) -> Self {
212        let this = Self {
213            id,
214            confirm: false,
215            send_flow: true,
216            state: ChannelState::default(),
217            receiver_state: ChannelReceiverStates::default(),
218            recovery_context: None,
219            killswitch: KillSwitch::default(),
220            internal_rpc,
221        };
222        this.update_rpc_status();
223        this
224    }
225
226    fn update_rpc_status(&self) {
227        self.internal_rpc
228            .set_channel_status(self.id, self.killswitch.clone());
229    }
230
231    fn set_reconnecting(&mut self, error: Error, topology: ChannelDefinition) -> Error {
232        self.state = ChannelState::Reconnecting;
233        std::mem::take(&mut self.killswitch).kill();
234        self.receiver_state.reset();
235        match self.recovery_context.as_ref() {
236            Some(ctx) => ctx.cause(),
237            None => {
238                let ctx = ChannelRecoveryContext::new(error, topology);
239                let error = ctx.cause();
240                self.recovery_context = Some(ctx);
241                error
242            }
243        }
244    }
245
246    pub(crate) fn finalize_connection(&mut self) {
247        self.state = ChannelState::Connected;
248        self.update_rpc_status();
249        if let Some(ctx) = self.recovery_context.take() {
250            ctx.finalize_recovery();
251        }
252    }
253
254    fn notifier(&self) -> Option<Notifier> {
255        Some(self.recovery_context.as_ref()?.notifier())
256    }
257}