How to do proxy and TLS in golang | 易学教程

问题

I am trying to route my requests through a proxy and also sending cert.pem in TLS config. Below code is throwing this error - proxyconnect tcp: tls: first record does not look like a TLS handshake. When I change the proxy URL from https to HTTP, the same code works. However proxy URL with https works in python. Below is my code so far

certs := x509.NewCertPool()
pemFile, err := ioutil.ReadFile("cert.pem")
if err != nil {
    return
}
certs.AppendCertsFromPEM(pemFile)
tlsConfig := &tls.Config{
    RootCAs: certs,
}

proxyUrl, err := url.Parse("https://someproxyurlhere.com:8080")
if err != nil {
    return
}

t := &http.Transport{
    TLSClientConfig: tlsConfig,
    Proxy:           http.ProxyURL(proxyUrl),
}

client := http.Client{
    Transport: t,
}

reqBody := "some JSON body here"

buff, err := json.Marshal(reqBody)
if err != nil {
    return
}

req, err := http.NewRequest(http.MethodPost, "https://someurlhere.com", bytes.NewBuffer(buff))
if err != nil {
    return
}

res, err := client.Do(req)
if err != nil {
    // Error here - proxyconnect tcp: tls: first record does not look like a TLS handshake
    return
}
defer res.Body.Close()

Python code

import requests
os.environ['HTTPS_PROXY'] = 'https://someproxyurlhere.com:8080'
response = requests.post("https://someurlhere.com",
                           json={'key': 'value'},
                           verify='cert.pem')
print(str(response.content))

回答1:

When I change the proxy URL from https to HTTP, the same code works.

https://..

proxyconnect tcp: tls: first record does not look like a TLS handshake.

This is because the proxy answers with an plain HTTP error to the strange HTTP request (which is actually the start of the TLS handshake).

However proxy URL with https works in python.

https://

openssl s_client

https://stackoverflow.com/questions/61401128/how-to-do-proxy-and-tls-in-golang