package proxy

import (
	"net"
	"net/http"
	"time"
)

// upstreamClient is the shared HTTP client for all upstream requests.
//
// It deliberately sets no overall Client.Timeout: the proxy streams
// arbitrarily large artifacts and the total time is bounded by the request
// context instead. Instead it constrains the phases that must never hang —
// connect, TLS handshake, and time-to-first-response-header — so a slow or
// wedged upstream cannot pin a goroutine and connection indefinitely.
var upstreamClient = &http.Client{
	Transport: &http.Transport{
		Proxy: http.ProxyFromEnvironment,
		DialContext: (&net.Dialer{
			Timeout:   10 * time.Second,
			KeepAlive: 30 * time.Second,
		}).DialContext,
		MaxIdleConns:          100,
		MaxIdleConnsPerHost:   10,
		IdleConnTimeout:       90 * time.Second,
		TLSHandshakeTimeout:   10 * time.Second,
		ExpectContinueTimeout: 1 * time.Second,
		ResponseHeaderTimeout: 30 * time.Second,
	},
}