# client.rs - source
Source of the Rust file `/home/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/reqwest-0.11.2/src/async_impl/client.rs`.
Keywords: rust, rustlang, rust-lang

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    #[cfg(any(feature = "native-tls", feature = "__rustls",))]
    use std::any::Any;
    use std::convert::TryInto;
    use std::net::IpAddr;
    use std::sync::Arc;
    use std::time::Duration;
    use std::{fmt, str};

    use bytes::Bytes;
    use http::header::{
        Entry, HeaderMap, HeaderValue, ACCEPT, ACCEPT_ENCODING, CONTENT_ENCODING, CONTENT_LENGTH,
        CONTENT_TYPE, LOCATION, PROXY_AUTHORIZATION, RANGE, REFERER, TRANSFER_ENCODING, USER_AGENT,
    };
    use http::uri::Scheme;
    use http::Uri;
    use hyper::client::ResponseFuture;
    #[cfg(feature = "native-tls-crate")]
    use native_tls_crate::TlsConnector;
    use pin_project_lite::pin_project;
    #[cfg(feature = "rustls-tls-native-roots")]
    use rustls::RootCertStore;
    use std::future::Future;
    use std::pin::Pin;
    use std::task::{Context, Poll};
    use tokio::time::Sleep;

    use log::debug;

    use super::decoder::Accepts;
    use super::request::{Request, RequestBuilder};
    use super::response::Response;
    use super::Body;
    use crate::connect::{Connector, HttpConnector};
    #[cfg(feature = "cookies")]
    use crate::cookie;
    use crate::error;
    use crate::into_url::{expect_uri, try_uri};
    use crate::redirect::{self, remove_sensitive_headers};
    #[cfg(feature = "__tls")]
    use crate::tls::TlsBackend;
    #[cfg(feature = "__tls")]
    use crate::Certificate;
    #[cfg(any(feature = "native-tls", feature = "__rustls"))]
    use crate::Identity;
    use crate::{IntoUrl, Method, Proxy, StatusCode, Url};

    /// An asynchronous `Client` to make Requests with.
    ///
    /// The Client has various configuration values to tweak, but the defaults
    /// are set to what is usually the most commonly desired value. To configure a
    /// `Client`, use `Client::builder()`.
    ///
    /// The `Client` holds a connection pool internally, so it is advised that
    /// you create one and **reuse** it.
    ///
    /// You do **not** have to wrap the `Client` it in an [`Rc`] or [`Arc`] to **reuse** it,
    /// because it already uses an [`Arc`] internally.
    ///
    /// [`Rc`]: std::rc::Rc
    #[derive(Clone)]
    pub struct Client {
        inner: Arc<ClientRef>,
    }

    /// A `ClientBuilder` can be used to create a `Client` with  custom configuration.
    #[must_use]
    pub struct ClientBuilder {
        config: Config,
    }

    struct Config {
        // NOTE: When adding a new field, update `fmt::Debug for ClientBuilder`
        accepts: Accepts,
        headers: HeaderMap,
        #[cfg(feature = "native-tls")]
        hostname_verification: bool,
        #[cfg(feature = "__tls")]
        certs_verification: bool,
        connect_timeout: Option<Duration>,
        connection_verbose: bool,
        pool_idle_timeout: Option<Duration>,
        pool_max_idle_per_host: usize,
        tcp_keepalive: Option<Duration>,
        #[cfg(any(feature = "native-tls", feature = "__rustls"))]
        identity: Option<Identity>,
        proxies: Vec<Proxy>,
        auto_sys_proxy: bool,
        redirect_policy: redirect::Policy,
        referer: bool,
        timeout: Option<Duration>,
        #[cfg(feature = "__tls")]
        root_certs: Vec<Certificate>,
        #[cfg(feature = "__tls")]
        tls_built_in_root_certs: bool,
        #[cfg(feature = "__tls")]
        tls: TlsBackend,
        http2_only: bool,
        http1_title_case_headers: bool,
        http2_initial_stream_window_size: Option<u32>,
        http2_initial_connection_window_size: Option<u32>,
        http2_adaptive_window: bool,
        http2_max_frame_size: Option<u32>,
        local_address: Option<IpAddr>,
        nodelay: bool,
        #[cfg(feature = "cookies")]
        cookie_store: Option<Arc<dyn cookie::CookieStore>>,
        trust_dns: bool,
        error: Option<crate::Error>,
        https_only: bool,
    }

    impl Default for ClientBuilder {
        fn default() -> Self {
            Self::new()
        }
    }

    impl ClientBuilder {
        /// Constructs a new `ClientBuilder`.
        ///
        /// This is the same as `Client::builder()`.
        pub fn new() -> ClientBuilder {
            let mut headers: HeaderMap<HeaderValue> = HeaderMap::with_capacity(2);
            headers.insert(ACCEPT, HeaderValue::from_static("*/*"));

            ClientBuilder {
                config: Config {
                    error: None,
                    accepts: Accepts::default(),
                    headers,
                    #[cfg(feature = "native-tls")]
                    hostname_verification: true,
                    #[cfg(feature = "__tls")]
                    certs_verification: true,
                    connect_timeout: None,
                    connection_verbose: false,
                    pool_idle_timeout: Some(Duration::from_secs(90)),
                    pool_max_idle_per_host: std::usize::MAX,
                    // TODO: Re-enable default duration once hyper's HttpConnector is fixed
                    // to no longer error when an option fails.
                    tcp_keepalive: None, //Some(Duration::from_secs(60)),
                    proxies: Vec::new(),
                    auto_sys_proxy: true,
                    redirect_policy: redirect::Policy::default(),
                    referer: true,
                    timeout: None,
                    #[cfg(feature = "__tls")]
                    root_certs: Vec::new(),
                    #[cfg(feature = "__tls")]
                    tls_built_in_root_certs: true,
                    #[cfg(any(feature = "native-tls", feature = "__rustls"))]
                    identity: None,
                    #[cfg(feature = "__tls")]
                    tls: TlsBackend::default(),
                    http2_only: false,
                    http1_title_case_headers: false,
                    http2_initial_stream_window_size: None,
                    http2_initial_connection_window_size: None,
                    http2_adaptive_window: false,
                    http2_max_frame_size: None,
                    local_address: None,
                    nodelay: true,
                    trust_dns: cfg!(feature = "trust-dns"),
                    #[cfg(feature = "cookies")]
                    cookie_store: None,
                    https_only: false,
                },
            }
        }

        /// Returns a `Client` that uses this `ClientBuilder` configuration.
        ///
        /// # Errors
        ///
        /// This method fails if TLS backend cannot be initialized, or the resolver
        /// cannot load the system configuration.
        pub fn build(self) -> crate::Result<Client> {
            let config = self.config;

            if let Some(err) = config.error {
                return Err(err);
            }

            let mut proxies = config.proxies;
            if config.auto_sys_proxy {
                proxies.push(Proxy::system());
            }
            let proxies = Arc::new(proxies);

            let mut connector = {
                #[cfg(feature = "__tls")]
                fn user_agent(headers: &HeaderMap) -> Option<HeaderValue> {
                    headers.get(USER_AGENT).cloned()
                }

                let http = match config.trust_dns {
                    false => HttpConnector::new_gai(),
                    #[cfg(feature = "trust-dns")]
                    true => HttpConnector::new_trust_dns()?,
                    #[cfg(not(feature = "trust-dns"))]
                    true => unreachable!("trust-dns shouldn't be enabled unless the feature is"),
                };

                #[cfg(feature = "__tls")]
                match config.tls {
                    #[cfg(feature = "default-tls")]
                    TlsBackend::Default => {
                        let mut tls = TlsConnector::builder();

                        #[cfg(feature = "native-tls")]
                        {
                            tls.danger_accept_invalid_hostnames(!config.hostname_verification);
                        }

                        tls.danger_accept_invalid_certs(!config.certs_verification);

                        tls.disable_built_in_roots(!config.tls_built_in_root_certs);

                        for cert in config.root_certs {
                            cert.add_to_native_tls(&mut tls);
                        }

                        #[cfg(feature = "native-tls")]
                        {
                            if let Some(id) = config.identity {
                                id.add_to_native_tls(&mut tls)?;
                            }
                        }

                        Connector::new_default_tls(
                            http,
                            tls,
                            proxies.clone(),
                            user_agent(&config.headers),
                            config.local_address,
                            config.nodelay,
                        )?
                    }
                    #[cfg(feature = "native-tls")]
                    TlsBackend::BuiltNativeTls(conn) => Connector::from_built_default_tls(
                        http,
                        conn,
                        proxies.clone(),
                        user_agent(&config.headers),
                        config.local_address,
                        config.nodelay,
                    ),
                    #[cfg(feature = "__rustls")]
                    TlsBackend::BuiltRustls(conn) => Connector::new_rustls_tls(
                        http,
                        conn,
                        proxies.clone(),
                        user_agent(&config.headers),
                        config.local_address,
                        config.nodelay,
                    ),
                    #[cfg(feature = "__rustls")]
                    TlsBackend::Rustls => {
                        use crate::tls::NoVerifier;

                        let mut tls = rustls::ClientConfig::new();
                        if config.http2_only {
                            tls.set_protocols(&["h2".into()]);
                        } else {
                            tls.set_protocols(&["h2".into(), "http/1.1".into()]);
                        }
                        #[cfg(feature = "rustls-tls-webpki-roots")]
                        if config.tls_built_in_root_certs {
                            tls.root_store
                                .add_server_trust_anchors(&webpki_roots::TLS_SERVER_ROOTS);
                        }
                        #[cfg(feature = "rustls-tls-native-roots")]
                        if config.tls_built_in_root_certs {
                            let roots_slice = NATIVE_ROOTS.as_ref().unwrap().roots.as_slice();
                            tls.root_store.roots.extend_from_slice(roots_slice);
                        }

                        if !config.certs_verification {
                            tls.dangerous()
                                .set_certificate_verifier(Arc::new(NoVerifier));
                        }

                        for cert in config.root_certs {
                            cert.add_to_rustls(&mut tls)?;
                        }

                        if let Some(id) = config.identity {
                            id.add_to_rustls(&mut tls)?;
                        }

                        Connector::new_rustls_tls(
                            http,
                            tls,
                            proxies.clone(),
                            user_agent(&config.headers),
                            config.local_address,
                            config.nodelay,
                        )
                    }
                    #[cfg(any(feature = "native-tls", feature = "__rustls",))]
                    TlsBackend::UnknownPreconfigured => {
                        return Err(crate::error::builder(
                            "Unknown TLS backend passed to `use_preconfigured_tls`",
                        ));
                    }
                }

                #[cfg(not(feature = "__tls"))]
                Connector::new(http, proxies.clone(), config.local_address, config.nodelay)
            };

            connector.set_timeout(config.connect_timeout);
            connector.set_verbose(config.connection_verbose);

            let mut builder = hyper::Client::builder();
            if config.http2_only {
                builder.http2_only(true);
            }

            if let Some(http2_initial_stream_window_size) = config.http2_initial_stream_window_size {
                builder.http2_initial_stream_window_size(http2_initial_stream_window_size);
            }
            if let Some(http2_initial_connection_window_size) =
                config.http2_initial_connection_window_size
            {
                builder.http2_initial_connection_window_size(http2_initial_connection_window_size);
            }
            if config.http2_adaptive_window {
                builder.http2_adaptive_window(true);
            }
            if let Some(http2_max_frame_size) = config.http2_max_frame_size {
                builder.http2_max_frame_size(http2_max_frame_size);
            }

            builder.pool_idle_timeout(config.pool_idle_timeout);
            builder.pool_max_idle_per_host(config.pool_max_idle_per_host);
            connector.set_keepalive(config.tcp_keepalive);

            if config.http1_title_case_headers {
                builder.http1_title_case_headers(true);
            }

            let hyper_client = builder.build(connector);

            let proxies_maybe_http_auth = proxies.iter().any(|p| p.maybe_has_http_auth());

            Ok(Client {
                inner: Arc::new(ClientRef {
                    accepts: config.accepts,
                    #[cfg(feature = "cookies")]
                    cookie_store: config.cookie_store,
                    hyper: hyper_client,
                    headers: config.headers,
                    redirect_policy: config.redirect_policy,
                    referer: config.referer,
                    request_timeout: config.timeout,
                    proxies,
                    proxies_maybe_http_auth,
                    https_only: config.https_only,
                }),
            })
        }

        // Higher-level options

        /// Sets the `User-Agent` header to be used by this client.
        ///
        /// # Example
        ///
        /// ```rust
        /// # async fn doc() -> Result<(), reqwest::Error> {
        /// // Name your user agent after your app?
        /// static APP_USER_AGENT: &str = concat!(
        ///     env!("CARGO_PKG_NAME"),
        ///     "/",
        ///     env!("CARGO_PKG_VERSION"),
        /// );
        ///
        /// let client = reqwest::Client::builder()
        ///     .user_agent(APP_USER_AGENT)
        ///     .build()?;
        /// let res = client.get("https://www.rust-lang.org").send().await?;
        /// # Ok(())
        /// # }
        /// ```
        pub fn user_agent<V>(mut self, value: V) -> ClientBuilder
        where
            V: TryInto<HeaderValue>,
            V::Error: Into<http::Error>,
        {
            match value.try_into() {
                Ok(value) => {
                    self.config.headers.insert(USER_AGENT, value);
                }
                Err(e) => {
                    self.config.error = Some(crate::error::builder(e.into()));
                }
            };
            self
        }
        /// Sets the default headers for every request.
        ///
        /// # Example
        ///
        /// ```rust
        /// use reqwest::header;
        /// # async fn doc() -> Result<(), reqwest::Error> {
        /// let mut headers = header::HeaderMap::new();
        /// headers.insert("X-MY-HEADER", header::HeaderValue::from_static("value"));
        ///
        /// // Consider marking security-sensitive headers with `set_sensitive`.
        /// let mut auth_value = header::HeaderValue::from_static("secret");
        /// auth_value.set_sensitive(true);
        /// headers.insert(header::AUTHORIZATION, auth_value);
        ///
        /// // get a client builder
        /// let client = reqwest::Client::builder()
        ///     .default_headers(headers)
        ///     .build()?;
        /// let res = client.get("https://www.rust-lang.org").send().await?;
        /// # Ok(())
        /// # }
        /// ```
        ///
        /// Override the default headers:
        ///
        /// ```rust
        /// use reqwest::header;
        /// # async fn doc() -> Result<(), reqwest::Error> {
        /// let mut headers = header::HeaderMap::new();
        /// headers.insert("X-MY-HEADER", header::HeaderValue::from_static("value"));
        ///
        /// // get a client builder
        /// let client = reqwest::Client::builder()
        ///     .default_headers(headers)
        ///     .build()?;
        /// let res = client
        ///     .get("https://www.rust-lang.org")
        ///     .header("X-MY-HEADER", "new_value")
        ///     .send()
        ///     .await?;
        /// # Ok(())
        /// # }
        /// ```
        pub fn default_headers(mut self, headers: HeaderMap) -> ClientBuilder {
            for (key, value) in headers.iter() {
                self.config.headers.insert(key, value.clone());
            }
            self
        }

        /// Enable a persistent cookie store for the client.
        ///
        /// Cookies received in responses will be preserved and included in
        /// additional requests.
        ///
        /// By default, no cookie store is used.
        ///
        /// # Optional
        ///
        /// This requires the optional `cookies` feature to be enabled.
        #[cfg(feature = "cookies")]
        #[cfg_attr(docsrs, doc(cfg(feature = "cookies")))]
        pub fn cookie_store(mut self, enable: bool) -> ClientBuilder {
            if enable {
                self.cookie_provider(Arc::new(cookie::Jar::default()))
            } else {
                self.config.cookie_store = None;
                self
            }
        }

        /// Set the persistent cookie store for the client.
        ///
        /// Cookies received in responses will be passed to this store, and
        /// additional requests will query this store for cookies.
        ///
        /// By default, no cookie store is used.
        ///
        /// # Optional
        ///
        /// This requires the optional `cookies` feature to be enabled.
        #[cfg(feature = "cookies")]
        #[cfg_attr(docsrs, doc(cfg(feature = "cookies")))]
        pub fn cookie_provider<C: cookie::CookieStore + 'static>(
            mut self,
            cookie_store: Arc<C>,
        ) -> ClientBuilder {
            self.config.cookie_store = Some(cookie_store as _);
            self
        }

        /// Enable auto gzip decompression by checking the `Content-Encoding` response header.
        ///
        /// If auto gzip decompression is turned on:
        ///
        /// - When sending a request and if the request's headers do not already contain
        ///   an `Accept-Encoding` **and** `Range` values, the `Accept-Encoding` header is set to `gzip`.
        ///   The request body is **not** automatically compressed.
        /// - When receiving a response, if it's headers contain a `Content-Encoding` value that
        ///   equals to `gzip`, both values `Content-Encoding` and `Content-Length` are removed from the
        ///   headers' set. The response body is automatically decompressed.
        ///
        /// If the `gzip` feature is turned on, the default option is enabled.
        ///
        /// # Optional
        ///
        /// This requires the optional `gzip` feature to be enabled
        #[cfg(feature = "gzip")]
        #[cfg_attr(docsrs, doc(cfg(feature = "gzip")))]
        pub fn gzip(mut self, enable: bool) -> ClientBuilder {
            self.config.accepts.gzip = enable;
            self
        }

        /// Enable auto brotli decompression by checking the `Content-Encoding` response header.
        ///
        /// If auto brotli decompression is turned on:
        ///
        /// - When sending a request and if the request's headers do not already contain
        ///   an `Accept-Encoding` **and** `Range` values, the `Accept-Encoding` header is set to `br`.
        ///   The request body is **not** automatically compressed.
        /// - When receiving a response, if it's headers contain a `Content-Encoding` value that
        ///   equals to `br`, both values `Content-Encoding` and `Content-Length` are removed from the
        ///   headers' set. The response body is automatically decompressed.
        ///
        /// If the `brotli` feature is turned on, the default option is enabled.
        ///
        /// # Optional
        ///
        /// This requires the optional `brotli` feature to be enabled
        #[cfg(feature = "brotli")]
        #[cfg_attr(docsrs, doc(cfg(feature = "brotli")))]
        pub fn brotli(mut self, enable: bool) -> ClientBuilder {
            self.config.accepts.brotli = enable;
            self
        }

        /// Disable auto response body gzip decompression.
        ///
        /// This method exists even if the optional `gzip` feature is not enabled.
        /// This can be used to ensure a `Client` doesn't use gzip decompression
        /// even if another dependency were to enable the optional `gzip` feature.
        pub fn no_gzip(self) -> ClientBuilder {
            #[cfg(feature = "gzip")]
            {
                self.gzip(false)
            }

            #[cfg(not(feature = "gzip"))]
            {
                self
            }
        }

        /// Disable auto response body brotli decompression.
        ///
        /// This method exists even if the optional `brotli` feature is not enabled.
        /// This can be used to ensure a `Client` doesn't use brotli decompression
        /// even if another dependency were to enable the optional `brotli` feature.
        pub fn no_brotli(self) -> ClientBuilder {
            #[cfg(feature = "brotli")]
            {
                self.brotli(false)
            }

            #[cfg(not(feature = "brotli"))]
            {
                self
            }
        }

        // Redirect options

        /// Set a `RedirectPolicy` for this client.
        ///
        /// Default will follow redirects up to a maximum of 10.
        pub fn redirect(mut self, policy: redirect::Policy) -> ClientBuilder {
            self.config.redirect_policy = policy;
            self
        }

        /// Enable or disable automatic setting of the `Referer` header.
        ///
        /// Default is `true`.
        pub fn referer(mut self, enable: bool) -> ClientBuilder {
            self.config.referer = enable;
            self
        }

        // Proxy options

        /// Add a `Proxy` to the list of proxies the `Client` will use.
        ///
        /// # Note
        ///
        /// Adding a proxy will disable the automatic usage of the "system" proxy.
        pub fn proxy(mut self, proxy: Proxy) -> ClientBuilder {
            self.config.proxies.push(proxy);
            self.config.auto_sys_proxy = false;
            self
        }

        /// Clear all `Proxies`, so `Client` will use no proxy anymore.
        ///
        /// This also disables the automatic usage of the "system" proxy.
        pub fn no_proxy(mut self) -> ClientBuilder {
            self.config.proxies.clear();
            self.config.auto_sys_proxy = false;
            self
        }

        // Timeout options

        /// Enables a request timeout.
        ///
        /// The timeout is applied from when the request starts connecting until the
        /// response body has finished.
        ///
        /// Default is no timeout.
        pub fn timeout(mut self, timeout: Duration) -> ClientBuilder {
            self.config.timeout = Some(timeout);
            self
        }

        /// Set a timeout for only the connect phase of a `Client`.
        ///
        /// Default is `None`.
        ///
        /// # Note
        ///
        /// This **requires** the futures be executed in a tokio runtime with
        /// a tokio timer enabled.
        pub fn connect_timeout(mut self, timeout: Duration) -> ClientBuilder {
            self.config.connect_timeout = Some(timeout);
            self
        }

        /// Set whether connections should emit verbose logs.
        ///
        /// Enabling this option will emit [log][] messages at the `TRACE` level
        /// for read and write operations on connections.
        ///
        /// [log]: https://crates.io/crates/log
        pub fn connection_verbose(mut self, verbose: bool) -> ClientBuilder {
            self.config.connection_verbose = verbose;
            self
        }

        // HTTP options

        /// Set an optional timeout for idle sockets being kept-alive.
        ///
        /// Pass `None` to disable timeout.
        ///
        /// Default is 90 seconds.
        pub fn pool_idle_timeout<D>(mut self, val: D) -> ClientBuilder
        where
            D: Into<Option<Duration>>,
        {
            self.config.pool_idle_timeout = val.into();
            self
        }

        /// Sets the maximum idle connection per host allowed in the pool.
        pub fn pool_max_idle_per_host(mut self, max: usize) -> ClientBuilder {
            self.config.pool_max_idle_per_host = max;
            self
        }

        /// Enable case sensitive headers.
        pub fn http1_title_case_headers(mut self) -> ClientBuilder {
            self.config.http1_title_case_headers = true;
            self
        }

        /// Only use HTTP/2.
        pub fn http2_prior_knowledge(mut self) -> ClientBuilder {
            self.config.http2_only = true;
            self
        }

        /// Sets the `SETTINGS_INITIAL_WINDOW_SIZE` option for HTTP2 stream-level flow control.
        ///
        /// Default is currently 65,535 but may change internally to optimize for common uses.
        pub fn http2_initial_stream_window_size(mut self, sz: impl Into<Option<u32>>) -> ClientBuilder {
            self.config.http2_initial_stream_window_size = sz.into();
            self
        }

        /// Sets the max connection-level flow control for HTTP2
        ///
        /// Default is currently 65,535 but may change internally to optimize for common uses.
        pub fn http2_initial_connection_window_size(
            mut self,
            sz: impl Into<Option<u32>>,
        ) -> ClientBuilder {
            self.config.http2_initial_connection_window_size = sz.into();
            self
        }

        /// Sets whether to use an adaptive flow control.
        ///
        /// Enabling this will override the limits set in `http2_initial_stream_window_size` and
        /// `http2_initial_connection_window_size`.
        pub fn http2_adaptive_window(mut self, enabled: bool) -> ClientBuilder {
            self.config.http2_adaptive_window = enabled;
            self
        }

        /// Sets the maximum frame size to use for HTTP2.
        ///
        /// Default is currently 16,384 but may change internally to optimize for common uses.
        pub fn http2_max_frame_size(mut self, sz: impl Into<Option<u32>>) -> ClientBuilder {
            self.config.http2_max_frame_size = sz.into();
            self
        }

        // TCP options

        /// Set whether sockets have `SO_NODELAY` enabled.
        ///
        /// Default is `true`.
        pub fn tcp_nodelay(mut self, enabled: bool) -> ClientBuilder {
            self.config.nodelay = enabled;
            self
        }

        /// Bind to a local IP Address.
        ///
        /// # Example
        ///
        /// ```
        /// use std::net::IpAddr;
        /// let local_addr = IpAddr::from([12, 4, 1, 8]);
        /// let client = reqwest::Client::builder()
        ///     .local_address(local_addr)
        ///     .build().unwrap();
        /// ```
        pub fn local_address<T>(mut self, addr: T) -> ClientBuilder
        where
            T: Into<Option<IpAddr>>,
        {
            self.config.local_address = addr.into();
            self
        }

        /// Set that all sockets have `SO_KEEPALIVE` set with the supplied duration.
        ///
        /// If `None`, the option will not be set.
        pub fn tcp_keepalive<D>(mut self, val: D) -> ClientBuilder
        where
            D: Into<Option<Duration>>,
        {
            self.config.tcp_keepalive = val.into();
            self
        }

        // TLS options

        /// Add a custom root certificate.
        ///
        /// This can be used to connect to a server that has a self-signed
        /// certificate for example.
        ///
        /// # Optional
        ///
        /// This requires the optional `default-tls`, `native-tls`, or `rustls-tls(-...)`
        /// feature to be enabled.
        #[cfg(feature = "__tls")]
        #[cfg_attr(
            docsrs,
            doc(cfg(any(
                feature = "default-tls",
                feature = "native-tls",
                feature = "rustls-tls"
            )))
        )]
        pub fn add_root_certificate(mut self, cert: Certificate) -> ClientBuilder {
            self.config.root_certs.push(cert);
            self
        }

        /// Controls the use of built-in/preloaded certificates during certificate validation.
        ///
        /// Defaults to `true` -- built-in system certs will be used.
        ///
        /// # Optional
        ///
        /// This requires the optional `default-tls`, `native-tls`, or `rustls-tls(-...)`
        /// feature to be enabled.
        #[cfg(feature = "__tls")]
        #[cfg_attr(
            docsrs,
            doc(cfg(any(
                feature = "default-tls",
                feature = "native-tls",
                feature = "rustls-tls"
            )))
        )]
        pub fn tls_built_in_root_certs(mut self, tls_built_in_root_certs: bool) -> ClientBuilder {
            self.config.tls_built_in_root_certs = tls_built_in_root_certs;
            self
        }

        /// Sets the identity to be used for client certificate authentication.
        ///
        /// # Optional
        ///
        /// This requires the optional `native-tls` or `rustls-tls(-...)` feature to be
        /// enabled.
        #[cfg(any(feature = "native-tls", feature = "__rustls"))]
        #[cfg_attr(docsrs, doc(cfg(any(feature = "native-tls", feature = "rustls-tls"))))]
        pub fn identity(mut self, identity: Identity) -> ClientBuilder {
            self.config.identity = Some(identity);
            self
        }

        /// Controls the use of hostname verification.
        ///
        /// Defaults to `false`.
        ///
        /// # Warning
        ///
        /// You should think very carefully before you use this method. If
        /// hostname verification is not used, any valid certificate for any
        /// site will be trusted for use from any other. This introduces a
        /// significant vulnerability to man-in-the-middle attacks.
        ///
        /// # Optional
        ///
        /// This requires the optional `native-tls` feature to be enabled.
        #[cfg(feature = "native-tls")]
        #[cfg_attr(docsrs, doc(cfg(feature = "native-tls")))]
        pub fn danger_accept_invalid_hostnames(
            mut self,
            accept_invalid_hostname: bool,
        ) -> ClientBuilder {
            self.config.hostname_verification = !accept_invalid_hostname;
            self
        }

        /// Controls the use of certificate validation.
        ///
        /// Defaults to `false`.
        ///
        /// # Warning
        ///
        /// You should think very carefully before using this method. If
        /// invalid certificates are trusted, *any* certificate for *any* site
        /// will be trusted for use. This includes expired certificates. This
        /// introduces significant vulnerabilities, and should only be used
        /// as a last resort.
        ///
        /// # Optional
        ///
        /// This requires the optional `default-tls`, `native-tls`, or `rustls-tls(-...)`
        /// feature to be enabled.
        #[cfg(feature = "__tls")]
        #[cfg_attr(
            docsrs,
            doc(cfg(any(
                feature = "default-tls",
                feature = "native-tls",
                feature = "rustls-tls"
            )))
        )]
        pub fn danger_accept_invalid_certs(mut self, accept_invalid_certs: bool) -> ClientBuilder {
            self.config.certs_verification = !accept_invalid_certs;
            self
        }

        /// Force using the native TLS backend.
        ///
        /// Since multiple TLS backends can be optionally enabled, this option will
        /// force the `native-tls` backend to be used for this `Client`.
        ///
        /// # Optional
        ///
        /// This requires the optional `native-tls` feature to be enabled.
        #[cfg(feature = "native-tls")]
        #[cfg_attr(docsrs, doc(cfg(feature = "native-tls")))]
        pub fn use_native_tls(mut self) -> ClientBuilder {
            self.config.tls = TlsBackend::Default;
            self
        }

        /// Force using the Rustls TLS backend.
        ///
        /// Since multiple TLS backends can be optionally enabled, this option will
        /// force the `rustls` backend to be used for this `Client`.
        ///
        /// # Optional
        ///
        /// This requires the optional `rustls-tls(-...)` feature to be enabled.
        #[cfg(feature = "__rustls")]
        #[cfg_attr(docsrs, doc(cfg(feature = "rustls-tls")))]
        pub fn use_rustls_tls(mut self) -> ClientBuilder {
            self.config.tls = TlsBackend::Rustls;
            self
        }

        /// Use a preconfigured TLS backend.
        ///
        /// If the passed `Any` argument is not a TLS backend that reqwest
        /// understands, the `ClientBuilder` will error when calling `build`.
        ///
        /// # Advanced
        ///
        /// This is an advanced option, and can be somewhat brittle. Usage requires
        /// keeping the preconfigured TLS argument version in sync with reqwest,
        /// since version mismatches will result in an "unknown" TLS backend.
        ///
        /// If possible, it's preferable to use the methods on `ClientBuilder`
        /// to configure reqwest's TLS.
        ///
        /// # Optional
        ///
        /// This requires one of the optional features `native-tls` or
        /// `rustls-tls(-...)` to be enabled.
        #[cfg(any(feature = "native-tls", feature = "__rustls",))]
        #[cfg_attr(docsrs, doc(cfg(any(feature = "native-tls", feature = "rustls-tls"))))]
        pub fn use_preconfigured_tls(mut self, tls: impl Any) -> ClientBuilder {
            let mut tls = Some(tls);
            #[cfg(feature = "native-tls")]
            {
                if let Some(conn) =
                    (&mut tls as &mut dyn Any).downcast_mut::<Option<native_tls_crate::TlsConnector>>()
                {
                    let tls = conn.take().expect("is definitely Some");
                    let tls = crate::tls::TlsBackend::BuiltNativeTls(tls);
                    self.config.tls = tls;
                    return self;
                }
            }
            #[cfg(feature = "__rustls")]
            {
                if let Some(conn) =
                    (&mut tls as &mut dyn Any).downcast_mut::<Option<rustls::ClientConfig>>()
                {
                    let tls = conn.take().expect("is definitely Some");
                    let tls = crate::tls::TlsBackend::BuiltRustls(tls);
                    self.config.tls = tls;
                    return self;
                }
            }

            // Otherwise, we don't recognize the TLS backend!
            self.config.tls = crate::tls::TlsBackend::UnknownPreconfigured;
            self
        }

        /// Enables the [trust-dns](trust_dns_resolver) async resolver instead of a default threadpool using `getaddrinfo`.
        ///
        /// If the `trust-dns` feature is turned on, the default option is enabled.
        ///
        /// # Optional
        ///
        /// This requires the optional `trust-dns` feature to be enabled
        #[cfg(feature = "trust-dns")]
        #[cfg_attr(docsrs, doc(cfg(feature = "trust-dns")))]
        pub fn trust_dns(mut self, enable: bool) -> ClientBuilder {
            self.config.trust_dns = enable;
            self
        }

        /// Disables the trust-dns async resolver.
        ///
        /// This method exists even if the optional `trust-dns` feature is not enabled.
        /// This can be used to ensure a `Client` doesn't use the trust-dns async resolver
        /// even if another dependency were to enable the optional `trust-dns` feature.
        pub fn no_trust_dns(self) -> ClientBuilder {
            #[cfg(feature = "trust-dns")]
            {
                self.trust_dns(false)
            }

            #[cfg(not(feature = "trust-dns"))]
            {
                self
            }
        }

        /// Restrict the Client to be used with HTTPS only requests.
        ///
        /// Defaults to false.
        pub fn https_only(mut self, enabled: bool) -> ClientBuilder {
            self.config.https_only = enabled;
            self
        }
    }

    type HyperClient = hyper::Client<Connector, super::body::ImplStream>;

    impl Default for Client {
        fn default() -> Self {
            Self::new()
        }
    }

    impl Client {
        /// Constructs a new `Client`.
        ///
        /// # Panics
        ///
        /// This method panics if TLS backend cannot initialized, or the resolver
        /// cannot load the system configuration.
        ///
        /// Use `Client::builder()` if you wish to handle the failure as an `Error`
        /// instead of panicking.
        pub fn new() -> Client {
            ClientBuilder::new().build().expect("Client::new()")
        }

        /// Creates a `ClientBuilder` to configure a `Client`.
        ///
        /// This is the same as `ClientBuilder::new()`.
        pub fn builder() -> ClientBuilder {
            ClientBuilder::new()
        }

        /// Convenience method to make a `GET` request to a URL.
        ///
        /// # Errors
        ///
        /// This method fails whenever 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 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 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 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 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 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
        /// request body before sending.
        ///
        /// # Errors
        ///
        /// This method fails whenever supplied `Url` cannot be parsed.
        pub fn request<U: IntoUrl>(&self, method: Method, url: U) -> RequestBuilder {
            let req = url.into_url().map(move |url| Request::new(method, url));
            RequestBuilder::new(self.clone(), 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 fn execute(
            &self,
            request: Request,
        ) -> impl Future<Output = Result<Response, crate::Error>> {
            self.execute_request(request)
        }

        pub(super) fn execute_request(&self, req: Request) -> Pending {
            let (method, url, mut headers, body, timeout) = req.pieces();
            if url.scheme() != "http" && url.scheme() != "https" {
                return Pending::new_err(error::url_bad_scheme(url));
            }

            // check if we're in https_only mode and check the scheme of the current URL
            if self.inner.https_only && url.scheme() != "https" {
                return Pending::new_err(error::url_bad_scheme(url));
            }

            // insert default headers in the request headers
            // without overwriting already appended headers.
            for (key, value) in &self.inner.headers {
                if let Entry::Vacant(entry) = headers.entry(key) {
                    entry.insert(value.clone());
                }
            }

            // Add cookies from the cookie store.
            #[cfg(feature = "cookies")]
            {
                if let Some(cookie_store) = self.inner.cookie_store.as_ref() {
                    if headers.get(crate::header::COOKIE).is_none() {
                        add_cookie_header(&mut headers, &**cookie_store, &url);
                    }
                }
            }

            let accept_encoding = self.inner.accepts.as_str();

            if let Some(accept_encoding) = accept_encoding {
                if !headers.contains_key(ACCEPT_ENCODING) && !headers.contains_key(RANGE) {
                    headers.insert(ACCEPT_ENCODING, HeaderValue::from_static(accept_encoding));
                }
            }

            let uri = expect_uri(&url);

            let (reusable, body) = match body {
                Some(body) => {
                    let (reusable, body) = body.try_reuse();
                    (Some(reusable), body)
                }
                None => (None, Body::empty()),
            };

            self.proxy_auth(&uri, &mut headers);

            let mut req = hyper::Request::builder()
                .method(method.clone())
                .uri(uri)
                .body(body.into_stream())
                .expect("valid request parts");

            let timeout = timeout
                .or(self.inner.request_timeout)
                .map(tokio::time::sleep)
                .map(Box::pin);

            *req.headers_mut() = headers.clone();

            let in_flight = self.inner.hyper.request(req);

            Pending {
                inner: PendingInner::Request(PendingRequest {
                    method,
                    url,
                    headers,
                    body: reusable,

                    urls: Vec::new(),

                    client: self.inner.clone(),

                    in_flight,
                    timeout,
                }),
            }
        }

        fn proxy_auth(&self, dst: &Uri, headers: &mut HeaderMap) {
            if !self.inner.proxies_maybe_http_auth {
                return;
            }

            // Only set the header here if the destination scheme is 'http',
            // since otherwise, the header will be included in the CONNECT tunnel
            // request instead.
            if dst.scheme() != Some(&Scheme::HTTP) {
                return;
            }

            if headers.contains_key(PROXY_AUTHORIZATION) {
                return;
            }

            for proxy in self.inner.proxies.iter() {
                if proxy.is_match(dst) {
                    if let Some(header) = proxy.http_basic_auth(dst) {
                        headers.insert(PROXY_AUTHORIZATION, header);
                    }

                    break;
                }
            }
        }
    }

    impl fmt::Debug for Client {
        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
            let mut builder = f.debug_struct("Client");
            self.inner.fmt_fields(&mut builder);
            builder.finish()
        }
    }

    impl fmt::Debug for ClientBuilder {
        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
            let mut builder = f.debug_struct("ClientBuilder");
            self.config.fmt_fields(&mut builder);
            builder.finish()
        }
    }

    impl Config {
        fn fmt_fields(&self, f: &mut fmt::DebugStruct<'_, '_>) {
            // Instead of deriving Debug, only print fields when their output
            // would provide relevant or interesting data.

            #[cfg(feature = "cookies")]
            {
                if let Some(_) = self.cookie_store {
                    f.field("cookie_store", &true);
                }
            }

            f.field("accepts", &self.accepts);

            if !self.proxies.is_empty() {
                f.field("proxies", &self.proxies);
            }

            if !self.redirect_policy.is_default() {
                f.field("redirect_policy", &self.redirect_policy);
            }

            if self.referer {
                f.field("referer", &true);
            }

            f.field("default_headers", &self.headers);

            if self.http1_title_case_headers {
                f.field("http1_title_case_headers", &true);
            }

            if self.http2_only {
                f.field("http2_prior_knowledge", &true);
            }

            if let Some(ref d) = self.connect_timeout {
                f.field("connect_timeout", d);
            }

            if let Some(ref d) = self.timeout {
                f.field("timeout", d);
            }

            if let Some(ref v) = self.local_address {
                f.field("local_address", v);
            }

            if self.nodelay {
                f.field("tcp_nodelay", &true);
            }

            #[cfg(feature = "native-tls")]
            {
                if !self.hostname_verification {
                    f.field("danger_accept_invalid_hostnames", &true);
                }
            }

            #[cfg(feature = "__tls")]
            {
                if !self.certs_verification {
                    f.field("danger_accept_invalid_certs", &true);
                }
            }

            #[cfg(all(feature = "native-tls-crate", feature = "__rustls"))]
            {
                f.field("tls_backend", &self.tls);
            }
        }
    }

    struct ClientRef {
        accepts: Accepts,
        #[cfg(feature = "cookies")]
        cookie_store: Option<Arc<dyn cookie::CookieStore>>,
        headers: HeaderMap,
        hyper: HyperClient,
        redirect_policy: redirect::Policy,
        referer: bool,
        request_timeout: Option<Duration>,
        proxies: Arc<Vec<Proxy>>,
        proxies_maybe_http_auth: bool,
        https_only: bool,
    }

    impl ClientRef {
        fn fmt_fields(&self, f: &mut fmt::DebugStruct<'_, '_>) {
            // Instead of deriving Debug, only print fields when their output
            // would provide relevant or interesting data.

            #[cfg(feature = "cookies")]
            {
                if let Some(_) = self.cookie_store {
                    f.field("cookie_store", &true);
                }
            }

            f.field("accepts", &self.accepts);

            if !self.proxies.is_empty() {
                f.field("proxies", &self.proxies);
            }

            if !self.redirect_policy.is_default() {
                f.field("redirect_policy", &self.redirect_policy);
            }

            if self.referer {
                f.field("referer", &true);
            }

            f.field("default_headers", &self.headers);

            if let Some(ref d) = self.request_timeout {
                f.field("timeout", d);
            }
        }
    }

    pin_project! {
        pub(super) struct Pending {
            #[pin]
            inner: PendingInner,
        }
    }

    enum PendingInner {
        Request(PendingRequest),
        Error(Option<crate::Error>),
    }

    pin_project! {
        struct PendingRequest {
            method: Method,
            url: Url,
            headers: HeaderMap,
            body: Option<Option<Bytes>>,

            urls: Vec<Url>,

            client: Arc<ClientRef>,

            #[pin]
            in_flight: ResponseFuture,
            #[pin]
            timeout: Option<Pin<Box<Sleep>>>,
        }
    }

    impl PendingRequest {
        fn in_flight(self: Pin<&mut Self>) -> Pin<&mut ResponseFuture> {
            self.project().in_flight
        }

        fn timeout(self: Pin<&mut Self>) -> Pin<&mut Option<Pin<Box<Sleep>>>> {
            self.project().timeout
        }

        fn urls(self: Pin<&mut Self>) -> &mut Vec<Url> {
            self.project().urls
        }

        fn headers(self: Pin<&mut Self>) -> &mut HeaderMap {
            self.project().headers
        }
    }

    impl Pending {
        pub(super) fn new_err(err: crate::Error) -> Pending {
            Pending {
                inner: PendingInner::Error(Some(err)),
            }
        }

        fn inner(self: Pin<&mut Self>) -> Pin<&mut PendingInner> {
            self.project().inner
        }
    }

    impl Future for Pending {
        type Output = Result<Response, crate::Error>;

        fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
            let inner = self.inner();
            match inner.get_mut() {
                PendingInner::Request(ref mut req) => Pin::new(req).poll(cx),
                PendingInner::Error(ref mut err) => Poll::Ready(Err(err
                    .take()
                    .expect("Pending error polled more than once"))),
            }
        }
    }

    impl Future for PendingRequest {
        type Output = Result<Response, crate::Error>;

        fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
            if let Some(delay) = self.as_mut().timeout().as_mut().as_pin_mut() {
                if let Poll::Ready(()) = delay.poll(cx) {
                    return Poll::Ready(Err(
                        crate::error::request(crate::error::TimedOut).with_url(self.url.clone())
                    ));
                }
            }

            loop {
                let res = match self.as_mut().in_flight().as_mut().poll(cx) {
                    Poll::Ready(Err(e)) => {
                        return Poll::Ready(Err(crate::error::request(e).with_url(self.url.clone())));
                    }
                    Poll::Ready(Ok(res)) => res,
                    Poll::Pending => return Poll::Pending,
                };

                #[cfg(feature = "cookies")]
                {
                    if let Some(ref cookie_store) = self.client.cookie_store {
                        let mut cookies =
                            cookie::extract_response_cookie_headers(&res.headers()).peekable();
                        if cookies.peek().is_some() {
                            cookie_store.set_cookies(&mut cookies, &self.url);
                        }
                    }
                }
                let should_redirect = match res.status() {
                    StatusCode::MOVED_PERMANENTLY | StatusCode::FOUND | StatusCode::SEE_OTHER => {
                        self.body = None;
                        for header in &[
                            TRANSFER_ENCODING,
                            CONTENT_ENCODING,
                            CONTENT_TYPE,
                            CONTENT_LENGTH,
                        ] {
                            self.headers.remove(header);
                        }

                        match self.method {
                            Method::GET | Method::HEAD => {}
                            _ => {
                                self.method = Method::GET;
                            }
                        }
                        true
                    }
                    StatusCode::TEMPORARY_REDIRECT | StatusCode::PERMANENT_REDIRECT => {
                        match self.body {
                            Some(Some(_)) | None => true,
                            Some(None) => false,
                        }
                    }
                    _ => false,
                };
                if should_redirect {
                    let loc = res.headers().get(LOCATION).and_then(|val| {
                        let loc = (|| -> Option<Url> {
                            // Some sites may send a utf-8 Location header,
                            // even though we're supposed to treat those bytes
                            // as opaque, we'll check specifically for utf8.
                            self.url.join(str::from_utf8(val.as_bytes()).ok()?).ok()
                        })();

                        // Check that the `url` is also a valid `http::Uri`.
                        //
                        // If not, just log it and skip the redirect.
                        let loc = loc.and_then(|url| {
                            if try_uri(&url).is_some() {
                                Some(url)
                            } else {
                                None
                            }
                        });

                        if loc.is_none() {
                            debug!("Location header had invalid URI: {:?}", val);
                        }
                        loc
                    });
                    if let Some(loc) = loc {
                        if self.client.referer {
                            if let Some(referer) = make_referer(&loc, &self.url) {
                                self.headers.insert(REFERER, referer);
                            }
                        }
                        let url = self.url.clone();
                        self.as_mut().urls().push(url);
                        let action = self
                            .client
                            .redirect_policy
                            .check(res.status(), &loc, &self.urls);

                        match action {
                            redirect::ActionKind::Follow => {
                                debug!("redirecting '{}' to '{}'", self.url, loc);
                                self.url = loc;

                                let mut headers =
                                    std::mem::replace(self.as_mut().headers(), HeaderMap::new());

                                remove_sensitive_headers(&mut headers, &self.url, &self.urls);
                                let uri = expect_uri(&self.url);
                                let body = match self.body {
                                    Some(Some(ref body)) => Body::reusable(body.clone()),
                                    _ => Body::empty(),
                                };
                                let mut req = hyper::Request::builder()
                                    .method(self.method.clone())
                                    .uri(uri.clone())
                                    .body(body.into_stream())
                                    .expect("valid request parts");

                                // Add cookies from the cookie store.
                                #[cfg(feature = "cookies")]
                                {
                                    if let Some(ref cookie_store) = self.client.cookie_store {
                                        add_cookie_header(&mut headers, &**cookie_store, &self.url);
                                    }
                                }

                                *req.headers_mut() = headers.clone();
                                std::mem::swap(self.as_mut().headers(), &mut headers);
                                *self.as_mut().in_flight().get_mut() = self.client.hyper.request(req);
                                continue;
                            }
                            redirect::ActionKind::Stop => {
                                debug!("redirect policy disallowed redirection to '{}'", loc);
                            }
                            redirect::ActionKind::Error(err) => {
                                return Poll::Ready(Err(crate::error::redirect(err, self.url.clone())));
                            }
                        }
                    }
                }

                debug!("response '{}' for {}", res.status(), self.url);
                let res = Response::new(
                    res,
                    self.url.clone(),
                    self.client.accepts,
                    self.timeout.take(),
                );
                return Poll::Ready(Ok(res));
            }
        }
    }

    impl fmt::Debug for Pending {
        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
            match self.inner {
                PendingInner::Request(ref req) => f
                    .debug_struct("Pending")
                    .field("method", &req.method)
                    .field("url", &req.url)
                    .finish(),
                PendingInner::Error(ref err) => f.debug_struct("Pending").field("error", err).finish(),
            }
        }
    }

    fn make_referer(next: &Url, previous: &Url) -> Option<HeaderValue> {
        if next.scheme() == "http" && previous.scheme() == "https" {
            return None;
        }

        let mut referer = previous.clone();
        let _ = referer.set_username("");
        let _ = referer.set_password(None);
        referer.set_fragment(None);
        referer.as_str().parse().ok()
    }

    #[cfg(feature = "cookies")]
    fn add_cookie_header(headers: &mut HeaderMap, cookie_store: &dyn cookie::CookieStore, url: &Url) {
        if let Some(header) = cookie_store.cookies(url) {
            headers.insert(crate::header::COOKIE, header);
        }
    }

    #[cfg(feature = "rustls-tls-native-roots")]
    lazy_static! {
        static ref NATIVE_ROOTS: std::io::Result<RootCertStore> =
            rustls_native_certs::load_native_certs().map_err(|e| e.1);
    }

    #[cfg(test)]
    mod tests {
        #[tokio::test]
        async fn execute_request_rejects_invald_urls() {
            let url_str = "hxxps://www.rust-lang.org/";
            let url = url::Url::parse(url_str).unwrap();
            let result = crate::get(url.clone()).await;

            assert!(result.is_err());
            let err = result.err().unwrap();
            assert!(err.is_builder());
            assert_eq!(url_str, err.url().unwrap().as_str());
        }
    }