drpc 0.2.3

Rust High Performance Async RPC Framework
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
148
149
150
151
152
153
154
155
156
157
158
159

use dark_std::err;
use dark_std::errors::Result;
use dark_std::sync::SyncHashMap;
use serde::de::DeserializeOwned;
use serde::Serialize;
use std::collections::HashMap;
use std::sync::Arc;
use std::time::Duration;
use tokio::time::sleep;

use crate::balance::{LoadBalance, LoadBalanceType};
use crate::client::Client;
use crate::codec::Codec;

/// To fetch remote service addr list

pub trait RegistryCenter: Sync + Send {
    /// Fetch [service]Vec<addr>
    async fn pull(&self) -> HashMap<String, Vec<String>>;
    async fn push(&self, service: String, addr: String, ex: Duration) -> Result<()>;
}

#[derive(Debug, Clone)]
pub struct ManagerConfig {
    pub balance: LoadBalanceType,
    pub interval: Duration,
}

impl ManagerConfig {
    pub fn new() -> Self {
        Self::default()
    }
    pub fn balance(mut self, balance: LoadBalanceType) -> Self {
        self.balance = balance;
        self
    }
    pub fn interval(mut self, d: Duration) -> Self {
        self.interval = d;
        self
    }
}

impl Default for ManagerConfig {
    fn default() -> Self {
        ManagerConfig {
            balance: LoadBalanceType::Round,
            interval: Duration::from_secs(5),
        }
    }
}

/// A connect manager that accepts a server addresses and make a client list.
pub struct BalanceManger<C: Codec, Registry: RegistryCenter> {
    pub config: ManagerConfig,
    pub clients: SyncHashMap<String, LoadBalance<Client<C>>>,
    pub fetcher: Arc<Registry>,
}

impl<C: Codec, Registry: RegistryCenter> BalanceManger<C, Registry> {
    pub fn new(cfg: ManagerConfig, f: Registry) -> Arc<Self>
    {
        Arc::new(Self {
            config: cfg,
            clients: SyncHashMap::new(),
            fetcher: Arc::new(f),
        })
    }

    /// pull addr list once
    pub async fn pull(&self) -> Result<()> {
        let addrs = self.fetcher.pull().await;
        if addrs.is_empty() {
            self.clients.clear();
        }
        for (s, addrs) in addrs {
            let balance = self.clients.get(&s);
            if let Some(clients) = balance {
                for addr in &addrs {
                    if !clients.contains(addr) {
                        let c = Client::dial(addr).await?;
                        clients.put(c);
                    }
                }
                let mut removes = vec![];
                for x in &clients.rpc_clients {
                    if !addrs.contains(&x.addr) {
                        removes.push(&x.addr);
                    }
                }
                for x in removes {
                    if let Some(client) = clients.remove(x) {
                        if Arc::strong_count(&client) <= 1 {
                            if let Ok(mut client) = Arc::try_unwrap(client) {
                                client.shutdown().await;
                            }
                        }
                    }
                }
            } else {
                let clients = LoadBalance::new();
                for x in addrs {
                    let c = Client::dial(&x).await?;
                    clients.put(c);
                }
                self.clients.insert(s, clients);
            }
        }
        return Ok(());
    }

    /// Spawn an loop pull
    pub async fn spawn_pull(&self) {
        loop {
            let r = self.pull().await;
            if r.is_err() {
                log::error!("service fetch fail:{}", r.err().unwrap());
            }
            sleep(self.config.interval).await;
        }
    }

    /// Push addr into register once
    pub async fn push(&self, service: String, addr: String) -> Result<()> {
        self.fetcher
            .push(
                service.clone(),
                addr.clone(),
                self.config.interval.clone() * 2,
            )
            .await
    }

    /// Spawn an loop push
    pub async fn spawn_push(&self, service: String, addr: String) {
        loop {
            let r = self.push(service.clone(), addr.clone()).await;
            if r.is_err() {
                log::error!("service fetch fail:{}", r.err().unwrap());
            }
            sleep(self.config.interval).await;
        }
    }

    pub async fn call<Arg, Resp>(&self, service: &str, func: &str, arg: Arg) -> Result<Resp>
        where
            Arg: Serialize,
            Resp: DeserializeOwned,
    {
        return match self
            .clients
            .get(service)
            .ok_or(err!("no service '{}' find!", service))?
            .do_balance(self.config.balance, service)
        {
            None => Err(err!("no service '{}' find!", service)),
            Some(c) => c.call(func, arg).await,
        };
    }
}