logo
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

use crate::middleware::Inner;
use crate::{middleware, PrerenderError, PrerenderMiddleware};
use actix_service::{Service, Transform};
use actix_utils::future;
use actix_utils::future::Ready;
use actix_web::body::{EitherBody, MessageBody};
use actix_web::dev::{ServiceRequest, ServiceResponse};
use actix_web::Error;
use reqwest::header::HeaderMap;
use reqwest::Client;
use std::rc::Rc;
use url::Url;

/// Builder for Prerender middleware.
///
/// To construct a Prerender middleware, call [`Prerender::build()`] to create a builder.
/// Then you can choose between `self..use_prerender_io`
///
/// # Errors
///
/// TODO
///
/// # Prerender.io example
/// ```
/// use actix_prerender::Prerender;
/// use actix_web::http::header;
///
/// let token = "prerender service token".to_string();
/// let prerender = Prerender::build().use_prerender_io(token);
///
/// // `prerender` can now be used in `App::wrap`.
/// ```
/// # Custom service URL example
/// ```
/// use actix_prerender::Prerender;
/// use actix_web::http::header;
///
/// let token = "prerender service token".to_string();
/// let prerender = Prerender::build().use_custom_prerender_url("https://localhost:5001");
///
/// // `prerender` can now be used in `App::wrap`.
/// ```
#[derive(Clone)]
pub struct Prerender {
    inner: Rc<Inner>,
}

#[derive()]
pub struct PrerenderBuilder {
    pub(crate) forward_headers: bool,
    pub(crate) before_render_fn: Option<fn(&ServiceRequest, &mut HeaderMap)>,
}

fn default_client() -> Client {
    Client::builder()
        .gzip(true)
        .timeout(std::time::Duration::new(25, 0))
        .build()
        .unwrap()
}

impl PrerenderBuilder {
    /// Creates a `Prerender` middleware that delegate requests to the web `prerender.io` service.
    pub fn use_prerender_io(self, token: String) -> Prerender {
        let inner = Inner {
            before_render_fn: self.before_render_fn,
            forward_headers: self.forward_headers,
            inner_client: default_client(),
            prerender_service_url: middleware::prerender_url(),
            prerender_token: Some(token),
        };

        Prerender { inner: Rc::new(inner) }
    }

    /// Creates a `Prerender` middleware that delegates crawler requests to the custom `prerender_service_url`.
    pub fn use_custom_prerender_url(self, prerender_service_url: &str) -> Result<Prerender, PrerenderError> {
        let prerender_service_url = Url::parse(prerender_service_url).map_err(|_| PrerenderError::InvalidUrl)?;

        let inner = Inner {
            before_render_fn: self.before_render_fn,
            forward_headers: self.forward_headers,
            inner_client: default_client(),
            prerender_service_url,
            prerender_token: None,
        };

        Ok(Prerender { inner: Rc::new(inner) })
    }

    /// Allow you to inspect and modify the `HeaderMap` before the request is sent to the `Prerender` service.
    pub fn set_before_render_fn(mut self, prerender_func: fn(req: &ServiceRequest, headers: &mut HeaderMap)) -> Self {
        self.before_render_fn = Some(prerender_func);
        self
    }

    /// Sets the middleware to forward all request headers to the `Prerender` service.
    pub const fn forward_headers(mut self) -> Self {
        self.forward_headers = true;
        self
    }
}

impl Prerender {
    pub fn build() -> PrerenderBuilder {
        PrerenderBuilder {
            forward_headers: false,
            before_render_fn: None,
        }
    }
}

impl<S, B> Transform<S, ServiceRequest> for Prerender
where
    S: Service<ServiceRequest, Response = ServiceResponse<B>, Error = Error>,
    S::Future: 'static,

    B: MessageBody + 'static,
{
    type Response = ServiceResponse<EitherBody<B>>;
    type Error = Error;
    type Transform = PrerenderMiddleware<S>;
    type InitError = ();
    type Future = Ready<Result<Self::Transform, Self::InitError>>;

    fn new_transform(&self, service: S) -> Self::Future {
        future::ok(PrerenderMiddleware {
            service,
            inner: Rc::clone(&self.inner),
        })
    }
}