feat(client): allow to config h2 max concurrent reset streams

Setting streams to 0 makes h2 work on wasm platforms without a
`Instant::now` implementation.

Author: boxdot

src/client/client.rs

@@ -1148,6 +1148,19 @@ impl Builder {
         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 10.
+    #[cfg(feature = "http2")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "http2")))]
+    pub fn http2_max_concurrent_reset_streams(&mut self, max: usize) -> &mut Self {
+        self.conn_builder.http2_max_concurrent_reset_streams(max);
+        self
+    }
+
     /// Set whether to retry requests that get disrupted before ever starting
     /// to write.
     ///

src/client/conn.rs

@@ -530,7 +530,8 @@ impl Builder {
         &mut self,
         enabled: bool,
     ) -> &mut Builder {
-        self.h1_parser_config.allow_spaces_after_header_name_in_responses(enabled);
+        self.h1_parser_config
+            .allow_spaces_after_header_name_in_responses(enabled);
         self
     }
 
@@ -701,6 +702,19 @@ impl Builder {
         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 10.
+    #[cfg(feature = "http2")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "http2")))]
+    pub fn http2_max_concurrent_reset_streams(&mut self, max: usize) -> &mut Self {
+        self.h2_builder.max_concurrent_reset_streams = max;
+        self
+    }
+
     /// Constructs a connection with the configured options and IO.
     pub fn handshake<T, B>(
         &self,

src/proto/h2/client.rs

@@ -10,7 +10,7 @@ use tokio::io::{AsyncRead, AsyncWrite};
 
 use super::{decode_content_length, ping, PipeToSendStream, SendBuf};
 use crate::body::HttpBody;
-use crate::common::{task, exec::Exec, Future, Never, Pin, Poll};
+use crate::common::{exec::Exec, task, Future, Never, Pin, Poll};
 use crate::headers;
 use crate::proto::Dispatched;
 use crate::{Body, Request, Response};
@@ -32,6 +32,10 @@ const DEFAULT_CONN_WINDOW: u32 = 1024 * 1024 * 5; // 5mb
 const DEFAULT_STREAM_WINDOW: u32 = 1024 * 1024 * 2; // 2mb
 const DEFAULT_MAX_FRAME_SIZE: u32 = 1024 * 16; // 16kb
 
+// Same as the default value in `h2`:
+// https://docs.rs/h2/0.3.3/h2/client/struct.Builder.html#method.max_concurrent_reset_streams
+const DEFAULT_MAX_CONCURRENT_RESET_STREAMS: usize = 10;
+
 #[derive(Clone, Debug)]
 pub(crate) struct Config {
     pub(crate) adaptive_window: bool,
@@ -44,6 +48,7 @@ pub(crate) struct Config {
     pub(crate) keep_alive_timeout: Duration,
     #[cfg(feature = "runtime")]
     pub(crate) keep_alive_while_idle: bool,
+    pub(crate) max_concurrent_reset_streams: usize,
 }
 
 impl Default for Config {
@@ -59,6 +64,7 @@ impl Default for Config {
             keep_alive_timeout: Duration::from_secs(20),
             #[cfg(feature = "runtime")]
             keep_alive_while_idle: false,
+            max_concurrent_reset_streams: DEFAULT_MAX_CONCURRENT_RESET_STREAMS,
         }
     }
 }
@@ -69,6 +75,7 @@ fn new_builder(config: &Config) -> Builder {
         .initial_window_size(config.initial_stream_window_size)
         .initial_connection_window_size(config.initial_conn_window_size)
         .max_frame_size(config.max_frame_size)
+        .max_concurrent_reset_streams(config.max_concurrent_reset_streams)
         .enable_push(false);
     builder
 }