Struct reqwest::ClientBuilder

pub struct ClientBuilder { /* fields omitted */ }

A ClientBuilder can be used to create a Client with custom configuration.

Implementations

impl ClientBuilder

pub fn new() -> ClientBuilder

This is supported on non-WebAssembly only.

Constructs a new ClientBuilder.

This is the same as Client::builder().

pub fn build(self) -> Result<Client>

This is supported on non-WebAssembly only.

Returns a Client that uses this ClientBuilder configuration.

Errors

This method fails if a TLS backend cannot be initialized, or the resolver cannot load the system configuration.

pub fn user_agent<V>(self, value: V) -> ClientBuilder where
    V: TryInto<HeaderValue>,
    V::Error: Into<Error>, 

This is supported on non-WebAssembly only.

Sets the User-Agent header to be used by this client.

Example

// 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?;

pub fn default_headers(self, headers: HeaderMap) -> ClientBuilder

This is supported on non-WebAssembly only.

Sets the default headers for every request.

Example

use reqwest::header;
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?;

Override the default headers:

use reqwest::header;
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?;

pub fn cookie_store(self, enable: bool) -> ClientBuilder

This is supported on non-WebAssembly and crate feature cookies only.

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.

pub fn cookie_provider<C: CookieStore + 'static>(
    self,
    cookie_store: Arc<C>
) -> ClientBuilder

This is supported on non-WebAssembly and crate feature cookies only.

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.

pub fn gzip(self, enable: bool) -> ClientBuilder

This is supported on non-WebAssembly and crate feature gzip only.

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 its headers contain a Content-Encoding value of gzip, both 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

pub fn brotli(self, enable: bool) -> ClientBuilder

This is supported on non-WebAssembly and crate feature brotli only.

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 its headers contain a Content-Encoding value of br, both 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

pub fn deflate(self, enable: bool) -> ClientBuilder

This is supported on non-WebAssembly and crate feature deflate only.

Enable auto deflate decompression by checking the Content-Encoding response header.

If auto deflate 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 deflate. The request body is not automatically compressed.
• When receiving a response, if it’s headers contain a Content-Encoding value that equals to deflate, both values Content-Encoding and Content-Length are removed from the headers’ set. The response body is automatically decompressed.

If the deflate feature is turned on, the default option is enabled.

Optional

This requires the optional deflate feature to be enabled

pub fn no_gzip(self) -> ClientBuilder

This is supported on non-WebAssembly only.

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_brotli(self) -> ClientBuilder

This is supported on non-WebAssembly only.

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_deflate(self) -> ClientBuilder

This is supported on non-WebAssembly only.

Disable auto response body deflate decompression.

This method exists even if the optional deflate feature is not enabled. This can be used to ensure a Client doesn’t use deflate decompression even if another dependency were to enable the optional deflate feature.

pub fn redirect(self, policy: Policy) -> ClientBuilder

This is supported on non-WebAssembly only.

Set a RedirectPolicy for this client.

Default will follow redirects up to a maximum of 10.

pub fn referer(self, enable: bool) -> ClientBuilder

This is supported on non-WebAssembly only.

Enable or disable automatic setting of the Referer header.

Default is true.

pub fn proxy(self, proxy: Proxy) -> ClientBuilder

This is supported on non-WebAssembly only.

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 no_proxy(self) -> ClientBuilder

This is supported on non-WebAssembly only.

Clear all Proxies, so Client will use no proxy anymore.

This also disables the automatic usage of the “system” proxy.

pub fn timeout(self, timeout: Duration) -> ClientBuilder

This is supported on non-WebAssembly only.

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 connect_timeout(self, timeout: Duration) -> ClientBuilder

This is supported on non-WebAssembly only.

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 connection_verbose(self, verbose: bool) -> ClientBuilder

This is supported on non-WebAssembly only.

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.

pub fn pool_idle_timeout<D>(self, val: D) -> ClientBuilder where
    D: Into<Option<Duration>>, 

This is supported on non-WebAssembly only.

Set an optional timeout for idle sockets being kept-alive.

Pass None to disable timeout.

Default is 90 seconds.

pub fn pool_max_idle_per_host(self, max: usize) -> ClientBuilder

This is supported on non-WebAssembly only.

Sets the maximum idle connection per host allowed in the pool.

pub fn http1_title_case_headers(self) -> ClientBuilder

This is supported on non-WebAssembly only.

Send headers as title case instead of lowercase.

pub fn http1_only(self) -> ClientBuilder

This is supported on non-WebAssembly only.

Only use HTTP/1.

pub fn http2_prior_knowledge(self) -> ClientBuilder

This is supported on non-WebAssembly only.

Only use HTTP/2.

pub fn http2_initial_stream_window_size(
    self,
    sz: impl Into<Option<u32>>
) -> ClientBuilder

This is supported on non-WebAssembly only.

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_connection_window_size(
    self,
    sz: impl Into<Option<u32>>
) -> ClientBuilder

This is supported on non-WebAssembly only.

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_adaptive_window(self, enabled: bool) -> ClientBuilder

This is supported on non-WebAssembly only.

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_max_frame_size(self, sz: impl Into<Option<u32>>) -> ClientBuilder

This is supported on non-WebAssembly only.

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 tcp_nodelay(self, enabled: bool) -> ClientBuilder

This is supported on non-WebAssembly only.

Set whether sockets have SO_NODELAY enabled.

Default is true.

pub fn local_address<T>(self, addr: T) -> ClientBuilder where
    T: Into<Option<IpAddr>>, 

This is supported on non-WebAssembly only.

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 tcp_keepalive<D>(self, val: D) -> ClientBuilder where
    D: Into<Option<Duration>>, 

This is supported on non-WebAssembly only.

Set that all sockets have SO_KEEPALIVE set with the supplied duration.

If None, the option will not be set.

pub fn add_root_certificate(self, cert: Certificate) -> ClientBuilder

This is supported on non-WebAssembly and (crate features default-tls or native-tls or rustls-tls) only.

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.

pub fn tls_built_in_root_certs(
    self,
    tls_built_in_root_certs: bool
) -> ClientBuilder

This is supported on non-WebAssembly and (crate features default-tls or native-tls or rustls-tls) only.

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.

pub fn identity(self, identity: Identity) -> ClientBuilder

This is supported on non-WebAssembly and (crate features native-tls or rustls-tls) only.

Sets the identity to be used for client certificate authentication.

Optional

This requires the optional native-tls or rustls-tls(-...) feature to be enabled.

pub fn danger_accept_invalid_hostnames(
    self,
    accept_invalid_hostname: bool
) -> ClientBuilder

This is supported on non-WebAssembly and crate feature native-tls only.

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.

pub fn danger_accept_invalid_certs(
    self,
    accept_invalid_certs: bool
) -> ClientBuilder

This is supported on non-WebAssembly and (crate features default-tls or native-tls or rustls-tls) only.

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.

pub fn min_tls_version(self, version: Version) -> ClientBuilder

This is supported on non-WebAssembly and (crate features default-tls or native-tls or rustls-tls) only.

Set the minimum required TLS version for connections.

By default the TLS backend’s own default is used.

Errors

A value of tls::Version::TLS_1_3 will cause an error with the native-tls/default-tls backend. This does not mean the version isn’t supported, just that it can’t be set as a minimum due to technical limitations.

Optional

This requires the optional default-tls, native-tls, or rustls-tls(-...) feature to be enabled.

pub fn max_tls_version(self, version: Version) -> ClientBuilder

This is supported on non-WebAssembly and (crate features default-tls or native-tls or rustls-tls) only.

Set the maximum allowed TLS version for connections.

By default there’s no maximum.

Errors

A value of tls::Version::TLS_1_3 will cause an error with the native-tls/default-tls backend. This does not mean the version isn’t supported, just that it can’t be set as a maximum due to technical limitations.

Optional

This requires the optional default-tls, native-tls, or rustls-tls(-...) feature to be enabled.

pub fn use_native_tls(self) -> ClientBuilder

This is supported on non-WebAssembly and crate feature native-tls only.

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.

pub fn use_rustls_tls(self) -> ClientBuilder

This is supported on non-WebAssembly and crate feature rustls-tls only.

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.

pub fn use_preconfigured_tls(self, tls: impl Any) -> ClientBuilder

This is supported on non-WebAssembly and (crate features native-tls or rustls-tls) only.

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.

pub fn trust_dns(self, enable: bool) -> ClientBuilder

This is supported on non-WebAssembly and crate feature trust-dns only.

Enables the trust-dns 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

pub fn no_trust_dns(self) -> ClientBuilder

This is supported on non-WebAssembly only.

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 https_only(self, enabled: bool) -> ClientBuilder

This is supported on non-WebAssembly only.

Restrict the Client to be used with HTTPS only requests.

Defaults to false.

pub fn resolve(self, domain: &str, addr: SocketAddr) -> ClientBuilder

This is supported on non-WebAssembly only.

Override DNS resolution for specific domains to particular IP addresses.

Warning

Since the DNS protocol has no notion of ports, if you wish to send traffic to a particular port you must include this port in the URL itself, any port in the overridden addr will be ignored and traffic sent to the conventional port for the given scheme (e.g. 80 for http).

Trait Implementations

impl Debug for ClientBuilder

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for ClientBuilder

fn default() -> Self

Returns the “default value” for a type.

impl From<ClientBuilder> for ClientBuilder

fn from(builder: ClientBuilder) -> Self

Performs the conversion.