elephantry 5.1.1

Object model manager for PostgreSQL
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

use std::collections::HashMap;

/**
 * Connections pool.
 */
#[derive(Clone, Debug, Default)]
pub struct Pool {
    default: String,
    connections: HashMap<String, crate::Connection>,
}

impl Pool {
    /**
     * Create a new pool with a default connection.
     */
    pub fn new(url: &str) -> crate::Result<Self> {
        Self::default().add_default("default", url)
    }

    /**
     * Create a new pool with a default connection from [`Config`].
     *
     * [`Config`]: crate::Config
     */
    pub fn from_config(config: &crate::Config) -> crate::Result<Self> {
        Self::default().add_default("default", &config.to_string())
    }

    /**
     * Add a default connection.
     */
    pub fn add_default(self, name: &str, url: &str) -> crate::Result<Self> {
        self.add(name, url, true)
    }

    /**
     * Add a connection.
     */
    pub fn add_connection(self, name: &str, url: &str) -> crate::Result<Self> {
        self.add(name, url, false)
    }

    fn add(mut self, name: &str, url: &str, default: bool) -> crate::Result<Self> {
        self.connections
            .insert(name.to_string(), crate::Connection::new(url)?);

        if default {
            self.set_default(name)?;
        }

        Ok(self)
    }

    /**
     * Retreive the default connection.
     */
    #[must_use]
    pub fn get_default(&self) -> Option<&crate::Connection> {
        self.get(&self.default)
    }

    /**
     * Set the connection `name` as default.
     */
    pub fn set_default(&mut self, name: &str) -> crate::Result {
        if !self.connections.contains_key(name) {
            return Err(crate::Error::Connect {
                dsn: name.to_string(),
                error: libpq::errors::Error::Backend(format!(
                    "Unable to set {name} connection as default, unknow connection"
                )),
            });
        }

        self.default = name.to_string();

        Ok(())
    }

    /**
     * Retreive the connection `name`, on `None` if not exists.
     */
    #[must_use]
    pub fn get(&self, name: &str) -> Option<&crate::Connection> {
        self.connections.get(name)
    }

    /**
     * Remove the connection `name`.
     */
    pub fn remove(&mut self, name: &str) {
        self.connections.remove(name);
    }
}

impl std::ops::Index<&str> for Pool {
    type Output = crate::Connection;

    fn index(&self, index: &str) -> &Self::Output {
        self.get(index).unwrap()
    }
}

impl std::ops::Deref for Pool {
    type Target = crate::Connection;

    fn deref(&self) -> &Self::Target {
        self.get_default().unwrap()
    }
}