this-rs 0.0.9

Framework for building complex multi-entity REST and GraphQL APIs with many relationships
Documentation 
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

//! Core types for the event log system

use serde::{Deserialize, Serialize};

/// Sequence number in the event log (monotonically increasing)
pub type SeqNo = u64;

/// Seek position for event log consumers
///
/// Determines where a consumer starts reading from when subscribing.
#[derive(Debug, Clone, Default, PartialEq, Serialize, Deserialize)]
pub enum SeekPosition {
    /// Start from the very beginning — replay all events
    Beginning,
    /// Resume from the last acknowledged position for this consumer
    LastAcknowledged,
    /// Start from now — only receive future events
    #[default]
    Latest,
    /// Start from a specific sequence number
    Sequence(SeqNo),
}

impl From<crate::config::SeekMode> for SeekPosition {
    fn from(mode: crate::config::SeekMode) -> Self {
        match mode {
            crate::config::SeekMode::Beginning => SeekPosition::Beginning,
            crate::config::SeekMode::LastAcknowledged => SeekPosition::LastAcknowledged,
            crate::config::SeekMode::Latest => SeekPosition::Latest,
        }
    }
}

/// State of a consumer group
#[derive(Debug, Clone)]
pub struct ConsumerState {
    /// Consumer group name
    pub name: String,
    /// Last acknowledged sequence number (None if never acked)
    pub last_acked: Option<SeqNo>,
}