Struct hyper::client::Builder

pub struct Builder { /* private fields */ }

A builder to configure a new Client.

Example

use std::time::Duration;
use hyper::Client;

let client = Client::builder()
    .pool_idle_timeout(Duration::from_secs(30))
    .http2_only(true)
    .build_http();

Implementations

impl Builder

pub fn pool_idle_timeout<D>(&mut self, val: D) -> &mut Self

where D: Into<Option<Duration>>,

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(&mut self, max_idle: usize) -> &mut Self

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

Default is usize::MAX (no limit).

pub fn http1_read_buf_exact_size(&mut self, sz: usize) -> &mut Self

Sets the exact size of the read buffer to always use.

Note that setting this option unsets the http1_max_buf_size option.

Default is an adaptive read buffer.

pub fn http1_max_buf_size(&mut self, max: usize) -> &mut Self

Set the maximum buffer size for the connection.

Default is ~400kb.

Note that setting this option unsets the http1_read_exact_buf_size option.

Panics

The minimum value allowed is 8192. This method panics if the passed max is less than the minimum.

pub fn http1_allow_spaces_after_header_name_in_responses( &mut self, val: bool ) -> &mut Self

Set whether HTTP/1 connections will accept spaces between header names and the colon that follow them in responses.

Newline codepoints (\r and \n) will be transformed to spaces when parsing.

You probably don’t need this, here is what RFC 7230 Section 3.2.4. has to say about it:

No whitespace is allowed between the header field-name and colon. In the past, differences in the handling of such whitespace have led to security vulnerabilities in request routing and response handling. A server MUST reject any received request message that contains whitespace between a header field-name and colon with a response code of 400 (Bad Request). A proxy MUST remove any such whitespace from a response message before forwarding the message downstream.

Note that this setting does not affect HTTP/2.

Default is false.

pub fn http1_allow_obsolete_multiline_headers_in_responses( &mut self, val: bool ) -> &mut Self

Set whether HTTP/1 connections will accept obsolete line folding for header values.

You probably don’t need this, here is what RFC 7230 Section 3.2.4. has to say about it:

A server that receives an obs-fold in a request message that is not within a message/http container MUST either reject the message by sending a 400 (Bad Request), preferably with a representation explaining that obsolete line folding is unacceptable, or replace each received obs-fold with one or more SP octets prior to interpreting the field value or forwarding the message downstream.

A proxy or gateway that receives an obs-fold in a response message that is not within a message/http container MUST either discard the message and replace it with a 502 (Bad Gateway) response, preferably with a representation explaining that unacceptable line folding was received, or replace each received obs-fold with one or more SP octets prior to interpreting the field value or forwarding the message downstream.

A user agent that receives an obs-fold in a response message that is not within a message/http container MUST replace each received obs-fold with one or more SP octets prior to interpreting the field value.

Note that this setting does not affect HTTP/2.

Default is false.

pub fn http1_ignore_invalid_headers_in_responses( &mut self, val: bool ) -> &mut Builder

Sets whether invalid header lines should be silently ignored in HTTP/1 responses.

This mimicks the behaviour of major browsers. You probably don’t want this. You should only want this if you are implementing a proxy whose main purpose is to sit in front of browsers whose users access arbitrary content which may be malformed, and they expect everything that works without the proxy to keep working with the proxy.

This option will prevent Hyper’s client from returning an error encountered when parsing a header, except if the error was caused by the character NUL (ASCII code 0), as Chrome specifically always reject those.

The ignorable errors are:

• empty header names;
• characters that are not allowed in header names, except for \0 and \r;
• when allow_spaces_after_header_name_in_responses is not enabled, spaces and tabs between the header name and the colon;
• missing colon between header name and colon;
• characters that are not allowed in header values except for \0 and \r.

If an ignorable error is encountered, the parser tries to find the next line in the input to resume parsing the rest of the headers. An error will be emitted nonetheless if it finds \0 or a lone \r while looking for the next line.

pub fn http1_writev(&mut self, enabled: bool) -> &mut Builder

Set whether HTTP/1 connections should try to use vectored writes, or always flatten into a single buffer.

Note that setting this to false may mean more copies of body data, but may also improve performance when an IO transport doesn’t support vectored writes well, such as most TLS implementations.

Setting this to true will force hyper to use queued strategy which may eliminate unnecessary cloning on some TLS backends

Default is auto. In this mode hyper will try to guess which mode to use

pub fn http1_title_case_headers(&mut self, val: bool) -> &mut Self

Set whether HTTP/1 connections will write header names as title case at the socket level.

Note that this setting does not affect HTTP/2.

Default is false.

pub fn http1_preserve_header_case(&mut self, val: bool) -> &mut Self

Set whether to support preserving original header cases.

Currently, this will record the original cases received, and store them in a private extension on the Response. It will also look for and use such an extension in any provided Request.

Since the relevant extension is still private, there is no way to interact with the original cases. The only effect this can have now is to forward the cases in a proxy-like fashion.

Note that this setting does not affect HTTP/2.

Default is false.

pub fn http09_responses(&mut self, val: bool) -> &mut Self

Set whether HTTP/0.9 responses should be tolerated.

Default is false.

pub fn http2_only(&mut self, val: bool) -> &mut Self

Set whether the connection must use HTTP/2.

The destination must either allow HTTP2 Prior Knowledge, or the Connect should be configured to do use ALPN to upgrade to h2 as part of the connection process. This will not make the Client utilize ALPN by itself.

Note that setting this to true prevents HTTP/1 from being allowed.

Default is false.

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

Sets the SETTINGS_INITIAL_WINDOW_SIZE option for HTTP2 stream-level flow control.

Passing None will do nothing.

If not set, hyper will use a default.

pub fn http2_initial_connection_window_size( &mut self, sz: impl Into<Option<u32>> ) -> &mut Self

Sets the max connection-level flow control for HTTP2

Passing None will do nothing.

If not set, hyper will use a default.

pub fn http2_adaptive_window(&mut self, enabled: bool) -> &mut 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_max_frame_size(&mut self, sz: impl Into<Option<u32>>) -> &mut Self

Sets the maximum frame size to use for HTTP2.

Passing None will do nothing.

If not set, hyper will use a default.

pub fn http2_keep_alive_interval( &mut self, interval: impl Into<Option<Duration>> ) -> &mut Self

Sets an interval for HTTP2 Ping frames should be sent to keep a connection alive.

Pass None to disable HTTP2 keep-alive.

Default is currently disabled.

Cargo Feature

Requires the runtime cargo feature to be enabled.

pub fn http2_keep_alive_timeout(&mut self, timeout: Duration) -> &mut Self

Sets a timeout for receiving an acknowledgement of the keep-alive ping.

If the ping is not acknowledged within the timeout, the connection will be closed. Does nothing if http2_keep_alive_interval is disabled.

Default is 20 seconds.

Cargo Feature

Requires the runtime cargo feature to be enabled.

pub fn http2_keep_alive_while_idle(&mut self, enabled: bool) -> &mut Self

Sets whether HTTP2 keep-alive should apply while the connection is idle.

If disabled, keep-alive pings are only sent while there are open request/responses streams. If enabled, pings are also sent when no streams are active. Does nothing if http2_keep_alive_interval is disabled.

Default is false.

Cargo Feature

Requires the runtime cargo feature to be enabled.

pub fn http2_max_concurrent_reset_streams(&mut self, max: usize) -> &mut Self

Sets the maximum number of HTTP2 concurrent locally reset streams.

See the documentation of h2::client::Builder::max_concurrent_reset_streams for more details.

The default value is determined by the h2 crate.

pub fn http2_max_send_buf_size(&mut self, max: usize) -> &mut Self

Set the maximum write buffer size for each HTTP/2 stream.

Default is currently 1MB, but may change.

Panics

The value must be no larger than u32::MAX.

pub fn retry_canceled_requests(&mut self, val: bool) -> &mut Self

Set whether to retry requests that get disrupted before ever starting to write.

This means a request that is queued, and gets given an idle, reused connection, and then encounters an error immediately as the idle connection was found to be unusable.

When this is set to false, the related ResponseFuture would instead resolve to an Error::Cancel.

Default is true.

pub fn set_host(&mut self, val: bool) -> &mut Self

Set whether to automatically add the Host header to requests.

If true, and a request does not include a Host header, one will be added automatically, derived from the authority of the Uri.

Default is true.

pub fn executor<E>(&mut self, exec: E) -> &mut Self

where E: Executor<Pin<Box<dyn Future<Output = ()> + Send>>> + Send + Sync + 'static,

Provide an executor to execute background Connection tasks.

pub fn build_http<B>(&self) -> Client<HttpConnector, B>

where B: HttpBody + Send, B::Data: Send,

Builder a client with this configuration and the default HttpConnector.

pub fn build<C, B>(&self, connector: C) -> Client<C, B>

where C: Connect + Clone, B: HttpBody + Send, B::Data: Send,

Combine the configuration of this builder with a connector to create a Client.

Trait Implementations

impl Clone for Builder

fn clone(&self) -> Builder

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Builder

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

Formats the value using the given formatter.

impl Default for Builder

fn default() -> Self

Returns the “default value” for a type.