Reproduction errors in http4s related to http4s/http4s/issues/1256. Requires running local web server, instructions and configuration for nginx are included.

http4s.scala

/*
  Reproduce errors for http4s. Some assembly is required. Most of this
  can be done with brew. These instructions use nginx (webserver) with
  the embedded configuration.  Backup any existing nginx.conf.

  NOTE: Test expects nginx to listent to port 80 - requires root privileges.
        ie. $ sudo brew services restart nginx


  #1 install nginx ($ brew install nginx)
  #2 create nginx configuration using command below or copy and paste
     to /usr/local/etc/nginx/nginx.conf
  $ cat - >| /usr/local/etc/nginx/nginx.conf <<'EOF'
worker_processes  1;

events {
    worker_connections  1024;
}

http {
  log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
                    '$status $body_bytes_sent "$http_referer" '
                    '"$http_user_agent" "$http_x_forwarded_for"';

  access_log         /usr/local/var/log/nginx/access.log  main;
  include            mime.types;
  default_type       application/octet-stream;
  sendfile           on;
  keepalive_timeout  65;

  server {
    listen 80;

    location / {
      alias /usr/local/var/www/;
    }
  }
}
EOF

  #3 Add test file to document root of webserver
  $ curl -so /usr/local/var/www/kml21.xsd https://developers.google.com/kml/schema/kml21.xsd

  #4 start http4s server with ammonite. (brew install ammonite-repl)
  $ amm http4s

  #5 After ammonite is running observe the logs and make several curl requests.
     Normally, by the the fourth request the server will report errors.
  $ curl -sv -o /dev/null --http1.0 localhost:8080/kml21.xsd

*/
// using ammonite start an http server to proxy requests to local webserver
import $ivy.`ch.qos.logback:logback-classic:1.2.3`
import $ivy.`org.http4s::http4s-dsl:0.18.15`
import $ivy.`org.http4s::http4s-blaze-server:0.18.15`
import $ivy.`org.http4s::http4s-blaze-client:0.18.15`

import cats.effect.IO
import org.http4s.client.blaze.Http1Client
import org.http4s.server.blaze.BlazeBuilder

import scala.concurrent.ExecutionContext.Implicits.global

Http1Client.stream[IO]().flatMap { client =>
  BlazeBuilder[IO]
    .bindHttp(8080, "127.0.0.1")
    .mountService(client.toHttpService, "/")
    .serve
}.compile.drain.unsafeRunSync