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

use core::marker::PhantomData;

use super::{IntoServiceFactory, ServiceFactory};

/// Adapt external config argument to a config for provided service factory
///
/// Note that this function consumes the receiving service factory and returns
/// a wrapped version of it.
pub fn map_config<I, SF, Req, F, Cfg>(factory: I, f: F) -> MapConfig<SF, Req, F, Cfg>
where
    I: IntoServiceFactory<SF, Req>,
    SF: ServiceFactory<Req>,
    F: Fn(Cfg) -> SF::Config,
{
    MapConfig::new(factory.into_factory(), f)
}

/// Replace config with unit.
pub fn unit_config<I, SF, Cfg, Req>(factory: I) -> UnitConfig<SF, Cfg, Req>
where
    I: IntoServiceFactory<SF, Req>,
    SF: ServiceFactory<Req, Config = ()>,
{
    UnitConfig::new(factory.into_factory())
}

/// `map_config()` adapter service factory
pub struct MapConfig<SF, Req, F, Cfg> {
    factory: SF,
    cfg_mapper: F,
    e: PhantomData<fn(Cfg, Req)>,
}

impl<SF, Req, F, Cfg> MapConfig<SF, Req, F, Cfg> {
    /// Create new `MapConfig` combinator
    pub(crate) fn new(factory: SF, cfg_mapper: F) -> Self
    where
        SF: ServiceFactory<Req>,
        F: Fn(Cfg) -> SF::Config,
    {
        Self {
            factory,
            cfg_mapper,
            e: PhantomData,
        }
    }
}

impl<SF, Req, F, Cfg> Clone for MapConfig<SF, Req, F, Cfg>
where
    SF: Clone,
    F: Clone,
{
    fn clone(&self) -> Self {
        Self {
            factory: self.factory.clone(),
            cfg_mapper: self.cfg_mapper.clone(),
            e: PhantomData,
        }
    }
}

impl<SF, Req, F, Cfg> ServiceFactory<Req> for MapConfig<SF, Req, F, Cfg>
where
    SF: ServiceFactory<Req>,
    F: Fn(Cfg) -> SF::Config,
{
    type Response = SF::Response;
    type Error = SF::Error;

    type Config = Cfg;
    type Service = SF::Service;
    type InitError = SF::InitError;
    type Future = SF::Future;

    fn new_service(&self, cfg: Self::Config) -> Self::Future {
        let mapped_cfg = (self.cfg_mapper)(cfg);
        self.factory.new_service(mapped_cfg)
    }
}

/// `unit_config()` config combinator
pub struct UnitConfig<SF, Cfg, Req> {
    factory: SF,
    _phantom: PhantomData<fn(Cfg, Req)>,
}

impl<SF, Cfg, Req> UnitConfig<SF, Cfg, Req>
where
    SF: ServiceFactory<Req, Config = ()>,
{
    /// Create new `UnitConfig` combinator
    pub(crate) fn new(factory: SF) -> Self {
        Self {
            factory,
            _phantom: PhantomData,
        }
    }
}

impl<SF, Cfg, Req> Clone for UnitConfig<SF, Cfg, Req>
where
    SF: Clone,
{
    fn clone(&self) -> Self {
        Self {
            factory: self.factory.clone(),
            _phantom: PhantomData,
        }
    }
}

impl<SF, Cfg, Req> ServiceFactory<Req> for UnitConfig<SF, Cfg, Req>
where
    SF: ServiceFactory<Req, Config = ()>,
{
    type Response = SF::Response;
    type Error = SF::Error;

    type Config = Cfg;
    type Service = SF::Service;
    type InitError = SF::InitError;
    type Future = SF::Future;

    fn new_service(&self, _: Cfg) -> Self::Future {
        self.factory.new_service(())
    }
}