anachro_icd/
arbitrator.rs

1//! # Arbitrator Messages
2//!
3//! These are messages that are sent FROM the central Arbitrator,
4//! to the peripheral Components/Clients.
5//!
6//! The [`Arbitrator` enum](enum.Arbitrator.html) is the top level
7//! message sent by the Arbitrator.
8
9use crate::{PubSubPath, Uuid};
10use serde::{Deserialize, Serialize};
11
12/// The primary Arbitrator mesage
13///
14/// These are all messages that are sent FROM the Arbitrator,
15/// TO the Components/Clients
16#[derive(Debug, Serialize, Deserialize, Eq, PartialEq)]
17pub enum Arbitrator<'a> {
18    /// Control messages
19    ///
20    /// Control messages are intended to be the primary
21    /// management channel between an Arbitrator and a
22    /// Component/Client
23    Control(Control),
24
25    /// Pub/Sub messages
26    ///
27    /// These are messages sent on the Publish/Subscribe
28    /// channel
29    #[serde(borrow)]
30    PubSub(Result<PubSubResponse<'a>, PubSubError>),
31
32    /// Object Store messages
33    ///
34    /// These are messages intended for the Object Store
35    /// channel for sending bulk messages.
36    ///
37    /// This functionality has not yet been implemented.
38    ObjStore,
39
40    /// Mailbox messages
41    ///
42    /// These are messages intended for the Mailbox layer,
43    /// including guaranteed delivery messages and bulk
44    /// message delivery
45    ///
46    /// This functionality has not yet been implemented.
47    Mailbox,
48}
49
50/// An Arbitrator Response to a Pub/Sub message
51///
52/// These are any Arbitrator -> Client relevant messages
53#[derive(Debug, Serialize, Deserialize, Eq, PartialEq)]
54pub enum PubSubResponse<'a> {
55    /// Subscription Acknowledgement
56    ///
57    /// Sent to acknowledge the reception of subscription
58    /// request from a client
59    SubAck {
60        #[serde(borrow)]
61        path: PubSubPath<'a>,
62    },
63
64    /// Subscription Message
65    ///
66    /// This is a "subscribed to" message, containing a
67    /// payload sent by another Client
68    SubMsg(SubMsg<'a>),
69}
70
71/// Subscription Message
72///
73/// This is a message that has been subscribed to by a
74/// client.
75#[derive(Debug, Serialize, Deserialize, Eq, PartialEq)]
76pub struct SubMsg<'a> {
77    /// The path that this message was sent to
78    ///
79    /// Note: If the client used wildcard subscribe(s), this
80    /// may not match the subscription text
81    #[serde(borrow)]
82    pub path: PubSubPath<'a>,
83
84    /// The payload sent along with the message
85    pub payload: &'a [u8],
86}
87
88/// Control Message
89///
90/// This is the 'control channel', used for establishing
91/// and managing connections between the Arbitrator and
92/// Client(s).
93#[derive(Debug, Serialize, Deserialize, Eq, PartialEq)]
94pub struct Control {
95    /// Sequence Number
96    ///
97    /// This number is provided by the client. The Arbitrator
98    /// will always respond with the same sequence number when
99    /// replying to a specific message
100    pub seq: u16,
101
102    /// Response
103    ///
104    /// The arbitrator response to the client request
105    pub response: Result<ControlResponse, ControlError>,
106}
107
108/// Control Response
109///
110/// A successful response to a Client's request
111#[derive(Debug, Serialize, Deserialize, Eq, PartialEq)]
112pub enum ControlResponse {
113    /// The client/component has registered
114    ComponentRegistration(Uuid),
115
116    /// The client has registered a Pub/Sub path shortcode
117    PubSubShortRegistration(u16),
118}
119
120/// Control Message Errors
121#[derive(Debug, Serialize, Deserialize, Eq, PartialEq)]
122pub enum ControlError {
123    NoWildcardsInShorts,
124    ResetConnection,
125}
126
127/// Publish/Subscribe Errors
128#[derive(Debug, Serialize, Deserialize, Eq, PartialEq)]
129pub enum PubSubError {}
130
131#[cfg(test)]
132mod test {
133    use super::*;
134    use postcard::{from_bytes, to_stdvec};
135
136    #[test]
137    fn ser_check() {
138        let uuid = Uuid::from_bytes([
139            0xd0, 0x36, 0xe7, 0x3b, 0x23, 0xec, 0x4f, 0x60, 0xac, 0xcb, 0x0e, 0xdd, 0xb6, 0x17,
140            0xf4, 0x71,
141        ]);
142        let msg = Arbitrator::Control(Control {
143            seq: 0x0405,
144            response: Ok(ControlResponse::ComponentRegistration(uuid)),
145        });
146
147        let ser_msg = to_stdvec(&msg).unwrap();
148        assert_eq!(
149            &ser_msg[..],
150            &[
151                0x00, // Arbitrator::Control
152                0x05, 0x04, // seq
153                0x00, // OK
154                0x00, // ControlResponse::ComponentRegistration
155                0xd0, 0x36, 0xe7, 0x3b, 0x23, 0xec, 0x4f, 0x60, 0xac, 0xcb, 0x0e, 0xdd, 0xb6, 0x17,
156                0xf4, 0x71,
157            ],
158        );
159
160        let deser_msg: Arbitrator = from_bytes(&ser_msg).unwrap();
161        assert_eq!(deser_msg, msg);
162    }
163}
anachro_icd/arbitrator.rs

anachro_icd/
arbitrator.rs
