liboxia 0.0.2

Liboxia is a Rust library designed for both native Rust applications and for integration with other languages via its C Foreign Function Interface (FFI). It serves as a client SDK for Oxia, a distributed key-value store, enabling robust, asynchronous data operations.
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
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

use crate::batch::{Batch, ReadBatch, WriteBatch};
use crate::errors::OxiaError;
use crate::errors::OxiaError::UnexpectedStatus;
use crate::operations::Operation;
use crate::provider_manager::ProviderManager;
use crate::shard_manager::ShardManager;
use crate::write_stream_manager::WriteStreamManager;
use log::info;
use std::sync::Arc;
use std::time::Duration;
use tokio::sync::mpsc::{UnboundedReceiver, UnboundedSender};
use tokio::sync::{mpsc, Mutex};
use tokio::task::JoinHandle;
use tokio::time::interval;
use tokio_util::sync::CancellationToken;

#[derive(Clone)]
pub enum Batcher {
    Read,
    Write,
}

impl Batcher {
    fn create_batch(
        &self,
        shard_id: i64,
        shard_manager: Arc<ShardManager>,
        provider_manager: Arc<ProviderManager>,
        write_stream_manager: Arc<WriteStreamManager>,
    ) -> Batch {
        match self {
            Batcher::Read => Batch::Read(ReadBatch::new(shard_id, shard_manager, provider_manager)),
            Batcher::Write => Batch::Write(WriteBatch::new(shard_id, write_stream_manager)),
        }
    }
}

pub struct BatchManager {
    context: CancellationToken,
    tx: UnboundedSender<Operation>,
    batch_handle: Arc<Mutex<Option<JoinHandle<()>>>>,
}

impl Drop for BatchManager {
    fn drop(&mut self) {
        self.context.cancel();
    }
}

impl BatchManager {
    pub fn new(
        shard_id: i64,
        batcher: Batcher,
        shard_manager: Arc<ShardManager>,
        provider_manager: Arc<ProviderManager>,
        write_stream_manager: Arc<WriteStreamManager>,
        batch_linger: Duration,
        batch_max_size: u32,
    ) -> Self {
        let (tx, rx) = mpsc::unbounded_channel();
        let context = CancellationToken::new();
        let handle = tokio::spawn(start_batcher(
            context.clone(),
            rx,
            shard_id,
            batcher,
            shard_manager,
            provider_manager,
            write_stream_manager,
            batch_linger,
            batch_max_size,
        ));
        BatchManager {
            context,
            tx,
            batch_handle: Arc::new(Mutex::new(Some(handle))),
        }
    }

    pub fn add(&self, operation: Operation) -> Result<(), OxiaError> {
        self.tx
            .send(operation)
            .map_err(|err| UnexpectedStatus(err.to_string()))?;
        Ok(())
    }

    pub async fn shutdown(self) -> Result<(), OxiaError> {
        self.context.cancel();
        let mut handle_guard = self.batch_handle.lock().await;
        if let Some(handle) = handle_guard.take() {
            handle
                .await
                .map_err(|err| UnexpectedStatus(err.to_string()))?;
        }
        Ok(())
    }
}

async fn start_batcher(
    context: CancellationToken,
    mut rx: UnboundedReceiver<Operation>,
    shard_id: i64,
    batcher: Batcher,
    shard_manager: Arc<ShardManager>,
    provider_manager: Arc<ProviderManager>,
    write_stream_manager: Arc<WriteStreamManager>,
    batch_linger: Duration,
    _batch_max_size: u32,
) {
    let mut buffer = Vec::new();
    let mut batch = batcher.create_batch(
        shard_id,
        shard_manager.clone(),
        provider_manager.clone(),
        write_stream_manager.clone(),
    );
    let mut interval = interval(batch_linger);
    loop {
        tokio::select! {
             _ = context.cancelled() => {
                info!("Exit batcher due to context canceled.");
                return
            },
            _ = interval.tick() => {
                if batch.is_empty() {
                   continue
                }
                batch.flush().await;
                batch = batcher.create_batch( shard_id, shard_manager.clone(), provider_manager.clone(), write_stream_manager.clone());
            }
            size = rx.recv_many(&mut buffer, usize::MAX) => {
                if size == 0 {
                    info!("Exit batcher due to channel closed.");
                    return
                }
                for operation  in buffer.drain(..) {
                    if !batch.can_add(&operation) {
                        batch.flush().await;
                        batch = batcher.create_batch( shard_id, shard_manager.clone(), provider_manager.clone(), write_stream_manager.clone());
                        interval.reset();
                    }
                    batch.add(operation);
                }
            }
        }
    }
}