feat:add installation for higress standalone in local docker environment (#606)

Co-authored-by: 澄潭 <zty98751@alibaba-inc.com>

pkg/cmd/hgctl/util/http_fetcher.go

@@ -0,0 +1,123 @@
+// Copyright (c) 2022 Alibaba Group Holding Ltd.
+//
+// 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 util
+
+import (
+	"context"
+	"crypto/tls"
+	"fmt"
+	"io"
+	"net/http"
+	"time"
+)
+
+const (
+	defaultInitialInterval = 500 * time.Millisecond
+	defaultMaxInterval     = 60 * time.Second
+)
+
+type HTTPFetcher struct {
+	client          *http.Client
+	initialBackoff  time.Duration
+	requestMaxRetry int
+	bufferSize      int64
+}
+
+// NewHTTPFetcher create a new HTTP remote fetcher.
+func NewHTTPFetcher(requestTimeout time.Duration, requestMaxRetry int, bufferSize int64) *HTTPFetcher {
+	if requestTimeout == 0 {
+		requestTimeout = 5 * time.Second
+	}
+	transport := http.DefaultTransport.(*http.Transport).Clone()
+	// nolint: gosec
+	// This is only when a user explicitly sets a flag to enable insecure mode
+	transport.TLSClientConfig = &tls.Config{InsecureSkipVerify: true}
+	return &HTTPFetcher{
+		client: &http.Client{
+			Timeout: requestTimeout,
+		},
+		initialBackoff:  defaultInitialInterval,
+		requestMaxRetry: requestMaxRetry,
+		bufferSize:      bufferSize,
+	}
+}
+
+// Fetch downloads with HTTP get.
+func (f *HTTPFetcher) Fetch(ctx context.Context, url string) ([]byte, error) {
+	c := f.client
+	delayInterval := f.initialBackoff
+	attempts := 0
+	var lastError error
+	for attempts < f.requestMaxRetry {
+		attempts++
+		req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
+		if err != nil {
+			return nil, err
+		}
+		resp, err := c.Do(req)
+		if err != nil {
+			lastError = err
+			if ctx.Err() != nil {
+				// If there is context timeout, exit this loop.
+				return nil, fmt.Errorf("download failed after %v attempts, last error: %v", attempts, lastError)
+			}
+			delayInterval = delayInterval + f.initialBackoff
+			if delayInterval > defaultMaxInterval {
+				break
+			}
+			time.Sleep(delayInterval)
+			continue
+		}
+		if resp.StatusCode == http.StatusOK {
+			body, err := io.ReadAll(io.LimitReader(resp.Body, f.bufferSize))
+			if err != nil {
+				return nil, err
+			}
+			err = resp.Body.Close()
+			if err != nil {
+				return nil, err
+			}
+			return body, err
+		}
+
+		lastError = fmt.Errorf("download request failed: status code %v", resp.StatusCode)
+
+		if retryable(resp.StatusCode) {
+			_, err := io.ReadAll(io.LimitReader(resp.Body, f.bufferSize))
+			if err != nil {
+				return nil, err
+			}
+			err = resp.Body.Close()
+			delayInterval = delayInterval + f.initialBackoff
+			if delayInterval > defaultMaxInterval {
+				break
+			}
+			time.Sleep(delayInterval)
+			continue
+		}
+
+		err = resp.Body.Close()
+		break
+
+	}
+	return nil, fmt.Errorf("download failed after %v attempts, last error: %v", attempts, lastError)
+}
+
+func retryable(code int) bool {
+	return code >= 500 &&
+		!(code == http.StatusNotImplemented ||
+			code == http.StatusHTTPVersionNotSupported ||
+			code == http.StatusNetworkAuthenticationRequired)
+}

pkg/cmd/hgctl/util/util.go

@@ -15,8 +15,10 @@
 package util
 
 import (
+	"bufio"
 	"fmt"
 	"net/url"
+	"os"
 	"strconv"
 	"strings"
 )
@@ -76,3 +78,18 @@ func ParseValue(valueStr string) any {
 	}
 	return value
 }
+
+// WriteFileString write string content to file
+func WriteFileString(fileName string, content string, perm os.FileMode) error {
+	file, err := os.OpenFile(fileName, os.O_CREATE|os.O_TRUNC|os.O_WRONLY, perm)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+	writer := bufio.NewWriter(file)
+	if _, err := writer.WriteString(content); err != nil {
+		return err
+	}
+	writer.Flush()
+	return nil
+}