Add load balancing network dialer

mtglib/network/proxy_dialer.go

@@ -0,0 +1,43 @@
+package network
+
+import (
+	"net/url"
+	"strconv"
+	"time"
+)
+
+const (
+	ProxyDialerOpenThreshold        = 5
+	ProxyDialerHalfOpenTimeout      = time.Minute
+	ProxyDialerResetFailuresTimeout = 10 * time.Second
+)
+
+func newProxyDialer(baseDialer Dialer, proxyURL *url.URL) Dialer {
+	params := proxyURL.Query()
+
+	var (
+		openThreshold        uint32 = ProxyDialerOpenThreshold
+		halfOpenTimeout             = ProxyDialerHalfOpenTimeout
+		resetFailuresTimeout        = ProxyDialerResetFailuresTimeout
+	)
+
+	if param := params.Get("open_threshold"); param != "" {
+		if intNum, err := strconv.ParseUint(param, 10, 32); err == nil {
+			openThreshold = uint32(intNum)
+		}
+	}
+
+	if param := params.Get("half_open_timeout"); param != "" {
+		if dur, err := time.ParseDuration(param); err == nil && dur > 0 {
+			halfOpenTimeout = dur
+		}
+	}
+
+	if param := params.Get("reset_failures_timeout"); param != "" {
+		if dur, err := time.ParseDuration(param); err == nil && dur > 0 {
+			resetFailuresTimeout = dur
+		}
+	}
+
+	return newCircuitBreakerDialer(baseDialer, openThreshold, halfOpenTimeout, resetFailuresTimeout)
+}