satex-load-balancer 0.5.2

Satex Load Balancer Library
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

use crate::health_check::{HealthCheck, HealthStatusObserve};
use crate::Backend;
use async_trait::async_trait;
use http::{HeaderMap, Response};
use satex_core::body::Body;
use satex_core::Error;
use std::time::Duration;

type Validator = Box<dyn Fn(&Response<Body>) -> Result<(), Error> + Send + Sync>;

pub struct HttpHealthCheck {
    path: String,
    headers: HeaderMap,
    validator: Validator,
    connect_timeout: Duration,
    override_port: Option<u16>,
    consecutive_success: usize,
    consecutive_failure: usize,
    status_observe: Option<Box<dyn HealthStatusObserve + Send + Sync>>,
}

impl HttpHealthCheck {
    pub fn new(path: String) -> Self {
        Self {
            path,
            consecutive_success: 1,
            consecutive_failure: 1,
            headers: Default::default(),
            validator: Box::new(|response| {
                if response.status().is_success() {
                    Ok(())
                } else {
                    Err(Error::new(format!(
                        "response status expecting 20x, but it is {}",
                        response.status().as_u16()
                    )))
                }
            }),
            connect_timeout: Duration::from_secs(1),
            override_port: None,
            status_observe: None,
        }
    }

    pub fn with_headers(self, headers: HeaderMap) -> Self {
        Self { headers, ..self }
    }

    pub fn with_validator(
        self,
        validator: impl Fn(&Response<Body>) -> Result<(), Error> + Send + Sync + 'static,
    ) -> Self {
        Self {
            validator: Box::new(validator),
            ..self
        }
    }

    pub fn with_connect_timeout(self, connect_timeout: Duration) -> Self {
        Self {
            connect_timeout,
            ..self
        }
    }

    pub fn with_override_port(self, port: u16) -> Self {
        Self {
            override_port: Some(port),
            ..self
        }
    }

    pub fn with_status_observe(
        self,
        status_observe: impl HealthStatusObserve + Send + Sync + 'static,
    ) -> Self {
        Self {
            status_observe: Some(Box::new(status_observe)),
            ..self
        }
    }

    pub fn with_consecutive_success(self, consecutive_success: usize) -> Self {
        Self {
            consecutive_success,
            ..self
        }
    }

    pub fn with_consecutive_failure(self, consecutive_failure: usize) -> Self {
        Self {
            consecutive_failure,
            ..self
        }
    }
}

#[async_trait]
impl HealthCheck for HttpHealthCheck {
    async fn check(&self, backend: &Backend) -> Result<(), Error> {
        todo!()
    }

    async fn status_change(&self, backend: &Backend, success: bool) {
        if let Some(status_observe) = &self.status_observe {
            status_observe.observe(backend, success).await;
        }
    }

    fn threshold(&self, success: bool) -> usize {
        if success {
            self.consecutive_success
        } else {
            self.consecutive_failure
        }
    }
}