Rework mage (#10417)

magefiles/utils/common.go

@@ -0,0 +1,113 @@
+/*
+Copyright 2023 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package utils
+
+import (
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"os"
+	"strings"
+	"time"
+)
+
+var DEBUG bool
+
+func init() {
+	DEBUG = false
+	debugENV := os.Getenv("MAGE_DEBUG")
+	if debugENV == "true" {
+		DEBUG = true
+	}
+}
+
+// CheckArgs should be used to ensure the right command line arguments are
+// passed before executing an example.
+func CheckArgs(arg ...string) {
+	if len(os.Args) < len(arg)+1 {
+		ErrorF("Usage: %s %s", os.Args[0], strings.Join(arg, " "))
+		os.Exit(1)
+	}
+}
+
+// CheckIfError should be used to naively panics if an error is not nil.
+func CheckIfError(err error, format string, args ...interface{}) {
+	if err == nil {
+		return
+	}
+
+	fmt.Printf("\x1b[31;1m%s ERROR %s %s\x1b[0m\n", timeStamp(), fmt.Sprintf(format, args...), err)
+	os.Exit(1)
+}
+
+// Info should be used to describe the example commands that are about to run.
+func Info(format string, args ...interface{}) {
+	fmt.Printf("\x1b[34;1m%s INFO: %s\x1b[0m\n", timeStamp(), fmt.Sprintf(format, args...))
+}
+
+func timeStamp() string {
+	t := time.Now()
+	return t.Format(time.RFC3339)
+}
+
+// Warning should be used to display a warning
+func Warning(format string, args ...interface{}) {
+	fmt.Printf("\x1b[36;1m%s WARNING: %s\x1b[0m\n", timeStamp(), fmt.Sprintf(format, args...))
+}
+
+// Info should be used to describe the example commands that are about to run.
+func Debug(format string, args ...interface{}) {
+	if DEBUG {
+		fmt.Printf("\x1b[34;1m%s DEBUG: %s\x1b[0m\n", timeStamp(), fmt.Sprintf(format, args...))
+	}
+}
+
+// Info should be used to describe the example commands that are about to run.
+func ErrorF(format string, args ...interface{}) {
+	fmt.Printf("\x1b[31;1m%s ERROR: %s\x1b[0m\n", timeStamp(), fmt.Sprintf(format, args...))
+}
+
+func DownloadFile(url string) (string, error) {
+	client := &http.Client{
+		Transport: &http.Transport{
+			DialContext: (&net.Dialer{
+				Timeout:   5 * time.Second,
+				KeepAlive: 5 * time.Second,
+			}).DialContext,
+			TLSHandshakeTimeout:   5 * time.Second,
+			ResponseHeaderTimeout: 5 * time.Second,
+			ExpectContinueTimeout: 1 * time.Second,
+			MaxIdleConnsPerHost:   -1,
+		},
+	}
+	resp, err := client.Get(url)
+	if err != nil {
+		return "", nil
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return "", errors.New(fmt.Sprintf("could not retrieve file, response from server %d for file %s", resp.StatusCode, url))
+	}
+	bodyBytes, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return "", nil
+	}
+	return string(bodyBytes), nil
+}