Http2.0 FRAME_SIZE_ERROR What doest that mean?

[cihangir]

Hey everyone trying to use http2 procotol with h2 crate and getting this error: Error: Error { kind: GoAway(b"", FRAME_SIZE_ERROR, Library) }
What can be wrong ?

Here is the example code that im using:

use h2::client;
use http::{HeaderMap, Request, Method,};
use std::error::Error;
use tokio::net::TcpStream;

#[tokio::main]
pub async fn main() -> Result<(), Box<dyn Error>> {
    // Establish TCP connection to the server.
    let tcp = TcpStream::connect("<ip>:443").await?;
    let (h2, connection) = client::handshake(tcp).await?;
    tokio::spawn(async move {
        connection.await.unwrap();
    });

    let mut h2 = h2.ready().await?;
    // Prepare the HTTP request to send to the server.
    let request = Request::builder()
    .uri("<url>")
    .header("user-agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/105.0.0.0 Safari/537.36")
    .body(())
    .unwrap();

    // Send the request. The second tuple item allows the caller
    // to stream a request body.
    let (response, _) = h2.send_request(request, true).unwrap();

    let (head, mut body) = response.await?.into_parts();

    println!("Received response: {:?}", head);

    // The `flow_control` handle allows the caller to manage
    // flow control.
    //
    // Whenever data is received, the caller is responsible for
    // releasing capacity back to the server once it has freed
    // the data from memory.
    let mut flow_control = body.flow_control().clone();

    while let Some(chunk) = body.data().await {
        let chunk = chunk?;
        println!("RX: {:?}", chunk);

        // Let the server send more data.
        let _ = flow_control.release_capacity(chunk.len());
    }

    Ok(())
}

[semicoleon]

Are you sure the server you're connecting to is assuming HTTP/2? h2 doesn't handle upgrading from HTTP/1.1 as documented under Handshake

[cihangir]

I have checked over console tab XHR and saw that there was writing h3 procotol so i assume must be supported h2 if h3 support exists

[semicoleon]

There are multiple ways for your browser to indicate protocol support, but the code you wrote isn't using any of them. Is there a reason you're using h2 as opposed to an HTTP client like reqwest?

[cihangir]

I have tried to use reqwest first by using ClientBuilder in reqwest - Rust
this method allowing for only http2 and got same error when i use reqwest and then moved the h2 library and again got this frame_size_error in h2 library too.
So i got same error for both library

[semicoleon]

Why are you trying to force HTTP/2?

To me that strongly suggests the server you're connecting to supports HTTP/1.1 and requires an upgrade mechanism to select a newer version.

[cihangir]

I just want to see the performance difference between h1-2-3 protocols.

[semicoleon]

You can enable the ALPN feature of reqwest and set the HTTP version on the RequestBuilder.

Cargo.toml:

[dependencies]
tokio = { version = "1.20.1", features = ["full"] }
reqwest = {version = "0.11.11", features = ["native-tls-alpn"]}

main.rs

use reqwest::{Client, Version};

#[tokio::main]
async fn main() {
    let client = Client::new();

    let response = client
        .get("https://google.com")
        // Causes an runtime error without native-tls-alpn feature
        .version(Version::HTTP_2)
        .send()
        .await
        .unwrap();

    assert_eq!(response.version(), Version::HTTP_2);
    println!("{:?}", response.version());
    println!("{:#?}", response)
}

Output:

HTTP/2.0
Response {
    url: Url {
        scheme: "https",
        cannot_be_a_base: false,
        username: "",
        password: None,
        host: Some(
            Domain(
                "www.google.com",
            ),
        ),
        port: None,
        path: "/",
        query: None,
        fragment: None,
    },
    status: 200,
    headers: {
        "date": "Sun, 11 Sep 2022 20:10:21 GMT",
        "expires": "-1",
        "cache-control": "private, max-age=0",
        "content-type": "text/html; charset=ISO-8859-1",
        // (and a bunch of other junk)
    },
}

[cihangir]

eyy awesome i wasnt expecting easy that much thanks a lot