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
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
use http::Extensions;
use reqwest::header::{HeaderMap, HeaderName, HeaderValue};
use reqwest::{Body, Client, IntoUrl, Method, Request, Response};
use serde::Serialize;
use std::convert::TryFrom;
use std::fmt::{self, Display};
use std::sync::Arc;

#[cfg(feature = "multipart")]
use reqwest::multipart;

use crate::error::Result;
use crate::middleware::{Middleware, Next};
use crate::RequestInitialiser;

/// A `ClientBuilder` is used to build a [`ClientWithMiddleware`].
///
/// [`ClientWithMiddleware`]: crate::ClientWithMiddleware
pub struct ClientBuilder {
    client: Client,
    middleware_stack: Vec<Arc<dyn Middleware>>,
    initialiser_stack: Vec<Arc<dyn RequestInitialiser>>,
}

impl ClientBuilder {
    pub fn new(client: Client) -> Self {
        ClientBuilder {
            client,
            middleware_stack: Vec::new(),
            initialiser_stack: Vec::new(),
        }
    }

    /// This method allows creating a ClientBuilder
    /// from an existing ClientWithMiddleware instance
    pub fn from_client(client_with_middleware: ClientWithMiddleware) -> Self {
        Self {
            client: client_with_middleware.inner,
            middleware_stack: client_with_middleware.middleware_stack.into_vec(),
            initialiser_stack: client_with_middleware.initialiser_stack.into_vec(),
        }
    }

    /// Convenience method to attach middleware.
    ///
    /// If you need to keep a reference to the middleware after attaching, use [`with_arc`].
    ///
    /// [`with_arc`]: Self::with_arc
    pub fn with<M>(self, middleware: M) -> Self
    where
        M: Middleware,
    {
        self.with_arc(Arc::new(middleware))
    }

    /// Add middleware to the chain. [`with`] is more ergonomic if you don't need the `Arc`.
    ///
    /// [`with`]: Self::with
    pub fn with_arc(mut self, middleware: Arc<dyn Middleware>) -> Self {
        self.middleware_stack.push(middleware);
        self
    }

    /// Convenience method to attach a request initialiser.
    ///
    /// If you need to keep a reference to the initialiser after attaching, use [`with_arc_init`].
    ///
    /// [`with_arc_init`]: Self::with_arc_init
    pub fn with_init<I>(self, initialiser: I) -> Self
    where
        I: RequestInitialiser,
    {
        self.with_arc_init(Arc::new(initialiser))
    }

    /// Add a request initialiser to the chain. [`with_init`] is more ergonomic if you don't need the `Arc`.
    ///
    /// [`with_init`]: Self::with_init
    pub fn with_arc_init(mut self, initialiser: Arc<dyn RequestInitialiser>) -> Self {
        self.initialiser_stack.push(initialiser);
        self
    }

    /// Returns a `ClientWithMiddleware` using this builder configuration.
    pub fn build(self) -> ClientWithMiddleware {
        ClientWithMiddleware {
            inner: self.client,
            middleware_stack: self.middleware_stack.into_boxed_slice(),
            initialiser_stack: self.initialiser_stack.into_boxed_slice(),
        }
    }
}

/// `ClientWithMiddleware` is a wrapper around [`reqwest::Client`] which runs middleware on every
/// request.
#[derive(Clone, Default)]
pub struct ClientWithMiddleware {
    inner: reqwest::Client,
    middleware_stack: Box<[Arc<dyn Middleware>]>,
    initialiser_stack: Box<[Arc<dyn RequestInitialiser>]>,
}

impl ClientWithMiddleware {
    /// See [`ClientBuilder`] for a more ergonomic way to build `ClientWithMiddleware` instances.
    pub fn new<T>(client: Client, middleware_stack: T) -> Self
    where
        T: Into<Box<[Arc<dyn Middleware>]>>,
    {
        ClientWithMiddleware {
            inner: client,
            middleware_stack: middleware_stack.into(),
            // TODO(conradludgate) - allow downstream code to control this manually if desired
            initialiser_stack: Box::new([]),
        }
    }

    /// Convenience method to make a `GET` request to a URL.
    ///
    /// # Errors
    ///
    /// This method fails whenever the supplied `Url` cannot be parsed.
    pub fn get<U: IntoUrl>(&self, url: U) -> RequestBuilder {
        self.request(Method::GET, url)
    }

    /// Convenience method to make a `POST` request to a URL.
    ///
    /// # Errors
    ///
    /// This method fails whenever the supplied `Url` cannot be parsed.
    pub fn post<U: IntoUrl>(&self, url: U) -> RequestBuilder {
        self.request(Method::POST, url)
    }

    /// Convenience method to make a `PUT` request to a URL.
    ///
    /// # Errors
    ///
    /// This method fails whenever the supplied `Url` cannot be parsed.
    pub fn put<U: IntoUrl>(&self, url: U) -> RequestBuilder {
        self.request(Method::PUT, url)
    }

    /// Convenience method to make a `PATCH` request to a URL.
    ///
    /// # Errors
    ///
    /// This method fails whenever the supplied `Url` cannot be parsed.
    pub fn patch<U: IntoUrl>(&self, url: U) -> RequestBuilder {
        self.request(Method::PATCH, url)
    }

    /// Convenience method to make a `DELETE` request to a URL.
    ///
    /// # Errors
    ///
    /// This method fails whenever the supplied `Url` cannot be parsed.
    pub fn delete<U: IntoUrl>(&self, url: U) -> RequestBuilder {
        self.request(Method::DELETE, url)
    }

    /// Convenience method to make a `HEAD` request to a URL.
    ///
    /// # Errors
    ///
    /// This method fails whenever the supplied `Url` cannot be parsed.
    pub fn head<U: IntoUrl>(&self, url: U) -> RequestBuilder {
        self.request(Method::HEAD, url)
    }

    /// Start building a `Request` with the `Method` and `Url`.
    ///
    /// Returns a `RequestBuilder`, which will allow setting headers and
    /// the request body before sending.
    ///
    /// # Errors
    ///
    /// This method fails whenever the supplied `Url` cannot be parsed.
    pub fn request<U: IntoUrl>(&self, method: Method, url: U) -> RequestBuilder {
        let req = RequestBuilder {
            inner: self.inner.request(method, url),
            extensions: Extensions::new(),
            middleware_stack: self.middleware_stack.clone(),
            initialiser_stack: self.initialiser_stack.clone(),
        };
        self.initialiser_stack
            .iter()
            .fold(req, |req, i| i.init(req))
    }

    /// Executes a `Request`.
    ///
    /// A `Request` can be built manually with `Request::new()` or obtained
    /// from a RequestBuilder with `RequestBuilder::build()`.
    ///
    /// You should prefer to use the `RequestBuilder` and
    /// `RequestBuilder::send()`.
    ///
    /// # Errors
    ///
    /// This method fails if there was an error while sending request,
    /// redirect loop was detected or redirect limit was exhausted.
    pub async fn execute(&self, req: Request) -> Result<Response> {
        let mut ext = Extensions::new();
        self.execute_with_extensions(req, &mut ext).await
    }

    /// Executes a `Request` with initial [`Extensions`].
    ///
    /// A `Request` can be built manually with `Request::new()` or obtained
    /// from a RequestBuilder with `RequestBuilder::build()`.
    ///
    /// You should prefer to use the `RequestBuilder` and
    /// `RequestBuilder::send()`.
    ///
    /// # Errors
    ///
    /// This method fails if there was an error while sending request,
    /// redirect loop was detected or redirect limit was exhausted.
    pub async fn execute_with_extensions(
        &self,
        req: Request,
        ext: &mut Extensions,
    ) -> Result<Response> {
        let next = Next::new(&self.inner, &self.middleware_stack);
        next.run(req, ext).await
    }
}

/// Create a `ClientWithMiddleware` without any middleware.
impl From<Client> for ClientWithMiddleware {
    fn from(client: Client) -> Self {
        ClientWithMiddleware {
            inner: client,
            middleware_stack: Box::new([]),
            initialiser_stack: Box::new([]),
        }
    }
}

impl fmt::Debug for ClientWithMiddleware {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        // skipping middleware_stack field for now
        f.debug_struct("ClientWithMiddleware")
            .field("inner", &self.inner)
            .finish_non_exhaustive()
    }
}

mod service {
    use std::{
        future::Future,
        pin::Pin,
        task::{Context, Poll},
    };

    use crate::Result;
    use http::Extensions;
    use reqwest::{Request, Response};

    use crate::{middleware::BoxFuture, ClientWithMiddleware, Next};

    // this is meant to be semi-private, same as reqwest's pending
    pub struct Pending {
        inner: BoxFuture<'static, Result<Response>>,
    }

    impl Unpin for Pending {}

    impl Future for Pending {
        type Output = Result<Response>;

        fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
            self.inner.as_mut().poll(cx)
        }
    }

    impl tower_service::Service<Request> for ClientWithMiddleware {
        type Response = Response;
        type Error = crate::Error;
        type Future = Pending;

        fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<()>> {
            self.inner.poll_ready(cx).map_err(crate::Error::Reqwest)
        }

        fn call(&mut self, req: Request) -> Self::Future {
            let inner = self.inner.clone();
            let middlewares = self.middleware_stack.clone();
            let mut extensions = Extensions::new();
            Pending {
                inner: Box::pin(async move {
                    let next = Next::new(&inner, &middlewares);
                    next.run(req, &mut extensions).await
                }),
            }
        }
    }

    impl tower_service::Service<Request> for &'_ ClientWithMiddleware {
        type Response = Response;
        type Error = crate::Error;
        type Future = Pending;

        fn poll_ready(&mut self, cx: &mut Context<'_>) -> Poll<Result<()>> {
            (&self.inner).poll_ready(cx).map_err(crate::Error::Reqwest)
        }

        fn call(&mut self, req: Request) -> Self::Future {
            let inner = self.inner.clone();
            let middlewares = self.middleware_stack.clone();
            let mut extensions = Extensions::new();
            Pending {
                inner: Box::pin(async move {
                    let next = Next::new(&inner, &middlewares);
                    next.run(req, &mut extensions).await
                }),
            }
        }
    }
}

/// This is a wrapper around [`reqwest::RequestBuilder`] exposing the same API.
#[must_use = "RequestBuilder does nothing until you 'send' it"]
pub struct RequestBuilder {
    inner: reqwest::RequestBuilder,
    middleware_stack: Box<[Arc<dyn Middleware>]>,
    initialiser_stack: Box<[Arc<dyn RequestInitialiser>]>,
    extensions: Extensions,
}

impl RequestBuilder {
    /// Assemble a builder starting from an existing `Client` and a `Request`.
    pub fn from_parts(client: ClientWithMiddleware, request: Request) -> RequestBuilder {
        let inner = reqwest::RequestBuilder::from_parts(client.inner, request);
        RequestBuilder {
            inner,
            middleware_stack: client.middleware_stack,
            initialiser_stack: client.initialiser_stack,
            extensions: Extensions::new(),
        }
    }

    /// Add a `Header` to this Request.
    pub fn header<K, V>(self, key: K, value: V) -> Self
    where
        HeaderName: TryFrom<K>,
        <HeaderName as TryFrom<K>>::Error: Into<http::Error>,
        HeaderValue: TryFrom<V>,
        <HeaderValue as TryFrom<V>>::Error: Into<http::Error>,
    {
        RequestBuilder {
            inner: self.inner.header(key, value),
            ..self
        }
    }

    /// Add a set of Headers to the existing ones on this Request.
    ///
    /// The headers will be merged in to any already set.
    pub fn headers(self, headers: HeaderMap) -> Self {
        RequestBuilder {
            inner: self.inner.headers(headers),
            ..self
        }
    }

    #[cfg(not(target_arch = "wasm32"))]
    pub fn version(self, version: reqwest::Version) -> Self {
        RequestBuilder {
            inner: self.inner.version(version),
            ..self
        }
    }

    /// Enable HTTP basic authentication.
    ///
    /// ```rust
    /// # use anyhow::Error;
    ///
    /// # async fn run() -> Result<(), Error> {
    /// let client = reqwest_middleware::ClientWithMiddleware::from(reqwest::Client::new());
    /// let resp = client.delete("http://httpbin.org/delete")
    ///     .basic_auth("admin", Some("good password"))
    ///     .send()
    ///     .await?;
    /// # Ok(())
    /// # }
    /// ```
    pub fn basic_auth<U, P>(self, username: U, password: Option<P>) -> Self
    where
        U: Display,
        P: Display,
    {
        RequestBuilder {
            inner: self.inner.basic_auth(username, password),
            ..self
        }
    }

    /// Enable HTTP bearer authentication.
    pub fn bearer_auth<T>(self, token: T) -> Self
    where
        T: Display,
    {
        RequestBuilder {
            inner: self.inner.bearer_auth(token),
            ..self
        }
    }

    /// Set the request body.
    pub fn body<T: Into<Body>>(self, body: T) -> Self {
        RequestBuilder {
            inner: self.inner.body(body),
            ..self
        }
    }

    /// Enables a request timeout.
    ///
    /// The timeout is applied from when the request starts connecting until the
    /// response body has finished. It affects only this request and overrides
    /// the timeout configured using `ClientBuilder::timeout()`.
    pub fn timeout(self, timeout: std::time::Duration) -> Self {
        RequestBuilder {
            inner: self.inner.timeout(timeout),
            ..self
        }
    }

    #[cfg(feature = "multipart")]
    #[cfg_attr(docsrs, doc(cfg(feature = "multipart")))]
    pub fn multipart(self, multipart: multipart::Form) -> Self {
        RequestBuilder {
            inner: self.inner.multipart(multipart),
            ..self
        }
    }

    /// Modify the query string of the URL.
    ///
    /// Modifies the URL of this request, adding the parameters provided.
    /// This method appends and does not overwrite. This means that it can
    /// be called multiple times and that existing query parameters are not
    /// overwritten if the same key is used. The key will simply show up
    /// twice in the query string.
    /// Calling `.query(&[("foo", "a"), ("foo", "b")])` gives `"foo=a&foo=b"`.
    ///
    /// # Note
    /// This method does not support serializing a single key-value
    /// pair. Instead of using `.query(("key", "val"))`, use a sequence, such
    /// as `.query(&[("key", "val")])`. It's also possible to serialize structs
    /// and maps into a key-value pair.
    ///
    /// # Errors
    /// This method will fail if the object you provide cannot be serialized
    /// into a query string.
    pub fn query<T: Serialize + ?Sized>(self, query: &T) -> Self {
        RequestBuilder {
            inner: self.inner.query(query),
            ..self
        }
    }

    /// Send a form body.
    ///
    /// Sets the body to the url encoded serialization of the passed value,
    /// and also sets the `Content-Type: application/x-www-form-urlencoded`
    /// header.
    ///
    /// ```rust
    /// # use anyhow::Error;
    /// # use std::collections::HashMap;
    /// #
    /// # async fn run() -> Result<(), Error> {
    /// let mut params = HashMap::new();
    /// params.insert("lang", "rust");
    ///
    /// let client = reqwest_middleware::ClientWithMiddleware::from(reqwest::Client::new());
    /// let res = client.post("http://httpbin.org")
    ///     .form(&params)
    ///     .send()
    ///     .await?;
    /// # Ok(())
    /// # }
    /// ```
    ///
    /// # Errors
    ///
    /// This method fails if the passed value cannot be serialized into
    /// url encoded format
    pub fn form<T: Serialize + ?Sized>(self, form: &T) -> Self {
        RequestBuilder {
            inner: self.inner.form(form),
            ..self
        }
    }

    /// Send a JSON body.
    ///
    /// # Optional
    ///
    /// This requires the optional `json` feature enabled.
    ///
    /// # Errors
    ///
    /// Serialization can fail if `T`'s implementation of `Serialize` decides to
    /// fail, or if `T` contains a map with non-string keys.
    #[cfg(feature = "json")]
    #[cfg_attr(docsrs, doc(cfg(feature = "json")))]
    pub fn json<T: Serialize + ?Sized>(self, json: &T) -> Self {
        RequestBuilder {
            inner: self.inner.json(json),
            ..self
        }
    }

    /// Disable CORS on fetching the request.
    ///
    /// # WASM
    ///
    /// This option is only effective with WebAssembly target.
    ///
    /// The [request mode][mdn] will be set to 'no-cors'.
    ///
    /// [mdn]: https://developer.mozilla.org/en-US/docs/Web/API/Request/mode
    pub fn fetch_mode_no_cors(self) -> Self {
        RequestBuilder {
            inner: self.inner.fetch_mode_no_cors(),
            ..self
        }
    }

    /// Build a `Request`, which can be inspected, modified and executed with
    /// `ClientWithMiddleware::execute()`.
    pub fn build(self) -> reqwest::Result<Request> {
        self.inner.build()
    }

    /// Build a `Request`, which can be inspected, modified and executed with
    /// `ClientWithMiddleware::execute()`.
    ///
    /// This is similar to [`RequestBuilder::build()`], but also returns the
    /// embedded `Client`.
    pub fn build_split(self) -> (ClientWithMiddleware, reqwest::Result<Request>) {
        let Self {
            inner,
            middleware_stack,
            initialiser_stack,
            ..
        } = self;
        let (inner, req) = inner.build_split();
        let client = ClientWithMiddleware {
            inner,
            middleware_stack,
            initialiser_stack,
        };
        (client, req)
    }

    /// Inserts the extension into this request builder
    pub fn with_extension<T: Send + Sync + Clone + 'static>(mut self, extension: T) -> Self {
        self.extensions.insert(extension);
        self
    }

    /// Returns a mutable reference to the internal set of extensions for this request
    pub fn extensions(&mut self) -> &mut Extensions {
        &mut self.extensions
    }

    /// Constructs the Request and sends it to the target URL, returning a
    /// future Response.
    ///
    /// # Errors
    ///
    /// This method fails if there was an error while sending request,
    /// redirect loop was detected or redirect limit was exhausted.
    ///
    /// # Example
    ///
    /// ```no_run
    /// # use anyhow::Error;
    /// #
    /// # async fn run() -> Result<(), Error> {
    /// let response = reqwest_middleware::ClientWithMiddleware::from(reqwest::Client::new())
    ///     .get("https://hyper.rs")
    ///     .send()
    ///     .await?;
    /// # Ok(())
    /// # }
    /// ```
    pub async fn send(mut self) -> Result<Response> {
        let mut extensions = std::mem::take(self.extensions());
        let (client, req) = self.build_split();
        client.execute_with_extensions(req?, &mut extensions).await
    }

    /// Attempt to clone the RequestBuilder.
    ///
    /// `None` is returned if the RequestBuilder can not be cloned,
    /// i.e. if the request body is a stream.
    ///
    /// # Examples
    ///
    /// ```
    /// # use reqwest::Error;
    /// #
    /// # fn run() -> Result<(), Error> {
    /// let client = reqwest_middleware::ClientWithMiddleware::from(reqwest::Client::new());
    /// let builder = client.post("http://httpbin.org/post")
    ///     .body("from a &str!");
    /// let clone = builder.try_clone();
    /// assert!(clone.is_some());
    /// # Ok(())
    /// # }
    /// ```
    pub fn try_clone(&self) -> Option<Self> {
        self.inner.try_clone().map(|inner| RequestBuilder {
            inner,
            middleware_stack: self.middleware_stack.clone(),
            initialiser_stack: self.initialiser_stack.clone(),
            extensions: self.extensions.clone(),
        })
    }
}

impl fmt::Debug for RequestBuilder {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        // skipping middleware_stack field for now
        f.debug_struct("RequestBuilder")
            .field("inner", &self.inner)
            .finish_non_exhaustive()
    }
}