H2 Client connection brakes when ALPN resolved to H2

[chamil321]

Description:

public function main() returns error? {
    http:Client restCountriesEp = check new ("https://www.dataaccess.com/webservicesserver");
    http:Response countries = check restCountriesEp->get("/NumberConversion.wso");
    test:assertEquals(countries.statusCode, 200, msg = "Found unexpected output");
}

Steps to reproduce:

error: HTTP/2 stream 3 reset by the remote peer

Affected Versions:

OS, DB, other environment details and versions:

Related Issues (optional):

Suggested Labels (optional):

Suggested Assignees (optional):

[Bhashinee]

Debugged the code and the following are the findings.

• ALPN negotiation is getting successfully negotiated to h2 and then we create the h2 pipeline and move on.
• Once we send the request client receives an RST frame from the server with the error code 1 which means an HTTP2 protocol error. That doesn't give us much information on the error.
  HTTP2 Protocol Error - The endpoint detected an unspecific protocol error. This error is for use when a more specific error code is not available.

trace logs

[2023-03-16 12:50:57,182] TRACE {http.tracelog.upstream} - [id: 0x8ced4fa1, L:/192.168.1.3:59482 - R:www.dataaccess.com/52.7.155.169:443] OUTBOUND SETTINGS: ack=false settings={MAX_HEADER_LIST_SIZE=8192}  
[2023-03-16 12:50:57,265] TRACE {http.tracelog.upstream} - [id: 0x8ced4fa1, L:/192.168.1.3:59482 - R:www.dataaccess.com/52.7.155.169:443] INBOUND SETTINGS: ack=false settings={=2, MAX_CONCURRENT_STREAMS=100, INITIAL_WINDOW_SIZE=1048576}  
[2023-03-16 12:50:57,267] TRACE {http.tracelog.upstream} - [id: 0x8ced4fa1, L:/192.168.1.3:59482 - R:www.dataaccess.com/52.7.155.169:443] OUTBOUND SETTINGS: ack=true  
[2023-03-16 12:50:57,269] TRACE {http.tracelog.upstream} - [id: 0x8ced4fa1, L:/192.168.1.3:59482 - R:www.dataaccess.com/52.7.155.169:443] INBOUND WINDOW_UPDATE: streamId=0 windowSizeIncrement=983041  
[2023-03-16 12:50:57,292] TRACE {http.tracelog.upstream} - [id: 0x8ced4fa1, L:/192.168.1.3:59482 - R:www.dataaccess.com/52.7.155.169:443] OUTBOUND HEADERS: streamId=3 headers=DefaultHttp2Headers[:path: /webservicesserver/NumberConversion.wso, :method: GET, :scheme: http, :authority: www.dataaccess.com, user-agent: ballerina] streamDependency=0 weight=16 exclusive=false padding=0 endStream=true  
[2023-03-16 12:50:57,485] TRACE {http.tracelog.upstream} - [id: 0x8ced4fa1, L:/192.168.1.3:59482 - R:www.dataaccess.com/52.7.155.169:443] INBOUND SETTINGS: ack=true  
[2023-03-16 12:50:57,521] TRACE {http.tracelog.upstream} - [id: 0x8ced4fa1, L:/192.168.1.3:59482 - R:www.dataaccess.com/52.7.155.169:443] INBOUND RST_STREAM: streamId=3 errorCode=1 

• I tried the same code with some other HTTP2-supported sites. And those work fine, which means that this is not happening for all the HTTP2 backends.

code

public function main() returns error? {
    http:Client restCountriesEp = check new ("https://www.wappalyzer.com/lookup");
    http:Response countries = check restCountriesEp->get("/wordpress.org/");
    io:println(countries.getTextPayload());
}

[dilanSachi]

Tested this with a nghttp client. These were the outgoing headers,

:method: GET
:path: /webservicesserver/NumberConversion.wso
:scheme: https
:authority: www.dataaccess.com
accept: */*
accept-encoding: gzip, deflate
user-agent: nghttp2/1.52.0

However, ballerina client outgoing headers are follows.

:path: /webservicesserver/NumberConversion.wso
:scheme: http
:authority: www.dataaccess.com
:method: GET
user-agent: ballerina

The difference here is that even though the url is https, ballerina client sends the scheme as http. When the scheme is updated to https in ballerina client, request is successful.

[github-actions]

This issue is NOT closed with a proper Reason/ label. Make sure to add proper reason label before closing. Please add or leave a comment with the proper reason label now.

      - Reason/EngineeringMistake - The issue occurred due to a mistake made in the past.
      - Reason/Regression - The issue has introduced a regression.
      - Reason/MultipleComponentInteraction - Issue occured due to interactions in multiple components.
      - Reason/Complex - Issue occurred due to complex scenario.
      - Reason/Invalid - Issue is invalid.
      - Reason/Other - None of the above cases.