Initial commit

internal/util/net/http/http.go

@@ -0,0 +1,41 @@
+package http
+
+import (
+	"io/ioutil"
+	"net/http"
+	"time"
+
+	"github.com/pkg/errors"
+)
+
+func GetBody(url string) ([]byte, error) {
+	client := http.Client{
+		Timeout: 30 * time.Second,
+	}
+	resp, err := client.Get(url)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	return ioutil.ReadAll(resp.Body)
+}
+
+func GetUntil(url string, stop <-chan struct{}) error {
+	client := http.Client{
+		Timeout: 1 * time.Second,
+	}
+	for {
+		select {
+		case <-stop:
+			return errors.Errorf("not available: %q", url)
+		default:
+			resp, err := client.Get(url)
+			if err != nil {
+				continue
+			}
+			resp.Body.Close()
+			return nil
+		}
+	}
+}

internal/util/net/net.go

@@ -0,0 +1,25 @@
+package net
+
+import (
+	"net"
+
+	"github.com/pkg/errors"
+)
+
+// DetectHostIPv4 attempts to determine the host IPv4 address by finding the
+// first non-loopback device with an assigned IPv4 address.
+func DetectHostIPv4() (string, error) {
+	addrs, err := net.InterfaceAddrs()
+	if err != nil {
+		return "", errors.WithStack(err)
+	}
+	for _, a := range addrs {
+		if ipnet, ok := a.(*net.IPNet); ok && !ipnet.IP.IsLoopback() {
+			if ipnet.IP.To4() == nil {
+				continue
+			}
+			return ipnet.IP.String(), nil
+		}
+	}
+	return "", errors.New("cannot detect host IPv4 address")
+}