Redpill of Golang disable http2

golang_disable_http2_main.go

package main

import (
	"fmt"
	"io/ioutil"
	"net/http"
	"os"
	"strings"

	resty "gopkg.in/resty.v1"
)

var _httpClient = &http.Client{
	Transport: &http.Transport{
		TLSClientConfig: nil, // will make client use http2
	},
}

func simpleRPC(nodeURL string, body string) (*[]byte, *string, *int, error) {
	req, err := http.NewRequest("POST", nodeURL, strings.NewReader(body))
	if err != nil {
		return nil, nil, nil, err
	}
	req.Header.Add("Content-Type", "application/json")
	resp, err := _httpClient.Do(req)
	if err != nil {
		return nil, nil, nil, err
	}

	if resp.StatusCode != http.StatusOK {
		return nil, nil, nil, fmt.Errorf("!StatusOK")
	}

	defer resp.Body.Close()
	respBody, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return nil, nil, nil, err
	}
	return &respBody, &resp.Proto, &resp.StatusCode, nil
}

func ForceDisableHttp2() {
	goDebugEnvSet := []string{"http2client=0"}
	for _, tEnv := range strings.Split(os.Getenv("GODEBUG"), ",") {
		if strings.Contains(tEnv, "http2client") {
			continue
		}
		goDebugEnvSet = append(goDebugEnvSet, strings.TrimSpace(tEnv))
	}
	os.Setenv("GODEBUG", strings.Join(goDebugEnvSet, ","))
}

func init() {
	ForceDisableHttp2() // enable / disable to test me
}

func main() {
	url := `https://WTF`
	payload := `{"WTF":true}`
	body, proto, statusCode, err := simpleRPC(url, payload)
	if err != nil {
		fmt.Println("normal failed", err)
	} else {
		fmt.Println("normal success", *proto, *statusCode, string(*body))
	}

	resp, err := resty.
		R().
		SetHeader("Content-Type", "application/json").
		SetBody(payload).
		Post(url)
	if err != nil {
		fmt.Println("resty failed", err)
	} else {
		fmt.Println("resty success", resp.RawResponse.Proto, resp.RawResponse.StatusCode, string(resp.Body()))
	}

}