resty 0.1.3

A fast, concurrent and multi-threadable REST 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
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181

use std::{
    marker::PhantomData,
    ops::{Deref, DerefMut},
};

use smol::io::AsyncWriteExt;

use crate::Error;

#[derive(Debug, Copy, Clone, PartialEq, Eq, PartialOrd, Ord)]
pub(crate) enum ResponseState {
    Status,
    StaticHeaders,
    Header,
    Body,
    Done,
}

pub type Writeable = std::pin::Pin<Box<dyn smol::io::AsyncWrite + Send>>;

/// A response with an optional Body and Error type
pub struct Response<'a, Body = (), Error = ()> {
    pub(crate) state: ResponseState,
    writeable: &'a mut Writeable,
    static_headers: &'static [(&'static str, &'static str)],
    once: bool,
    body: PhantomData<Body>,
    error: PhantomData<Error>,
}

impl<B, E> Deref for Response<'_, B, E> {
    type Target = std::pin::Pin<Box<dyn smol::io::AsyncWrite + Send>>;

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

impl<B, E> DerefMut for Response<'_, B, E> {
    fn deref_mut(&mut self) -> &mut Self::Target {
        &mut self.writeable
    }
}

impl<'a, B, E> Response<'a, B, E> {
    pub fn new(
        writeable: &'a mut Writeable,
        static_headers: &'static [(&'static str, &'static str)],
    ) -> Self {
        Self {
            state: ResponseState::Status,
            writeable,
            static_headers,
            once: false,
            body: PhantomData,
            error: PhantomData,
        }
    }

    pub async fn status(&mut self, code: u16, reason: &str) -> Result<(), Error> {
        if code < 100 || code >= 1000 || self.state != ResponseState::Status {
            return Err(Error::InvalidStatus);
        }

        let _ = self
            .writeable
            .write_all(format!("HTTP/1.1 {code} {reason}\r\n").as_bytes())
            .await;

        self.state = ResponseState::StaticHeaders;

        Box::pin(self.headers(&[])).await?;

        Ok(())
    }

    pub async fn headers(&mut self, headers: &[(&str, &str)]) -> Result<(), Error> {
        if self.state >= ResponseState::Body || self.state == ResponseState::Status {
            return Err(Error::StateError);
        }

        if self.state == ResponseState::StaticHeaders {
            self.state = ResponseState::Header;
            Box::pin(self.headers(self.static_headers)).await?;
        }

        for (name, value) in headers {
            if name.to_ascii_lowercase() == "connection" && *value == "close" {
                self.once = true;
            }
            let header = format!("{name}: {value}\r\n").into_bytes();
            self.writeable
                .write_all(&header)
                .await
                .map_err(|e| Error::WriteError(e))?;
        }

        Ok(())
    }

    /// Requires the Status Line to already be sent
    /// Prefer using the typed `ok` and `err` methods
    pub async fn send(&mut self, data: &impl Serialize) -> Result<(), Error> {
        if self.state != ResponseState::Header {
            return Err(Error::StateError);
        }

        let data = data.serialize().map_err(|_| Error::SerializeError)?;

        self.writeable
            .write_all(&format!("Content-Length: {}\r\n\r\n", data.len()).into_bytes())
            .await
            .map_err(Error::WriteError)?;

        self.writeable
            .write_all(&data)
            .await
            .map_err(Error::WriteError)?;

        let _ = self.writeable.flush().await;

        if self.once {
            let _ = self.writeable.close().await;
        }

        self.state = ResponseState::Done;

        Ok(())
    }

    pub async fn close(&mut self) {
        if self.state == ResponseState::Done {
            return;
        }
        let _ = self.status(500, "Internal Server Error").await;
        let _ = self.send(&"").await;
    }
}

impl<B: Serialize, E> Response<'_, B, E> {
    /// Send a response with 200 OK
    pub async fn ok(&mut self, body: &B) -> Result<(), Error> {
        self.status(200, "OK").await?;
        self.send(body).await
    }
}
impl<B, E: Serialize> Response<'_, B, E> {
    //Send an error with a given code and reason
    pub async fn err(&mut self, status: (u16, &str), err: &E) -> Result<(), Error> {
        let (code, reason) = status;
        self.status(code, reason).await?;
        self.send(err).await
    }
}

impl<'a, 'b: 'a> Response<'b> {
    pub fn as_typed<B, E>(
        &'a mut self,
        static_headers: &'static [(&'static str, &'static str)],
    ) -> Response<'a, B, E> {
        Response {
            state: self.state,
            writeable: self.writeable,
            static_headers: static_headers,
            once: self.once,
            body: PhantomData,
            error: PhantomData,
        }
    }
}

#[doc = include_str!("../docs/traits/Serialize.md")]
pub trait Serialize {
    fn serialize(&self) -> Result<Vec<u8>, Box<dyn std::error::Error>>;
}

impl<T: Into<Vec<u8>> + Clone> Serialize for T {
    fn serialize(&self) -> Result<Vec<u8>, Box<dyn std::error::Error>> {
        Ok(T::into(self.clone()))
    }
}