first to commit project

helper.go

@@ -0,0 +1,85 @@
+package cos
+
+import (
+	"bytes"
+	"crypto/md5"
+	"crypto/sha1"
+	"fmt"
+	"net/http"
+)
+
+// 计算 md5 或 sha1 时的分块大小
+const calDigestBlockSize = 1024 * 1024 * 10
+
+func calMD5Digest(msg []byte) []byte {
+	// TODO: 分块计算,减少内存消耗
+	m := md5.New()
+	m.Write(msg)
+	return m.Sum(nil)
+}
+
+func calSHA1Digest(msg []byte) []byte {
+	// TODO: 分块计算,减少内存消耗
+	m := sha1.New()
+	m.Write(msg)
+	return m.Sum(nil)
+}
+
+// cloneRequest returns a clone of the provided *http.Request. The clone is a
+// shallow copy of the struct and its Header map.
+func cloneRequest(r *http.Request) *http.Request {
+	// shallow copy of the struct
+	r2 := new(http.Request)
+	*r2 = *r
+	// deep copy of the Header
+	r2.Header = make(http.Header, len(r.Header))
+	for k, s := range r.Header {
+		r2.Header[k] = append([]string(nil), s...)
+	}
+	return r2
+}
+
+// encodeURIComponent like same function in javascript
+//
+// https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/encodeURIComponent
+//
+// http://www.ecma-international.org/ecma-262/6.0/#sec-uri-syntax-and-semantics
+func encodeURIComponent(s string) string {
+	var b bytes.Buffer
+	written := 0
+
+	for i, n := 0, len(s); i < n; i++ {
+		c := s[i]
+
+		switch c {
+		case '-', '_', '.', '!', '~', '*', '\'', '(', ')':
+			continue
+		default:
+			// Unreserved according to RFC 3986 sec 2.3
+			if 'a' <= c && c <= 'z' {
+
+				continue
+
+			}
+			if 'A' <= c && c <= 'Z' {
+
+				continue
+
+			}
+			if '0' <= c && c <= '9' {
+
+				continue
+			}
+		}
+
+		b.WriteString(s[written:i])
+		fmt.Fprintf(&b, "%%%02x", c)
+		written = i + 1
+	}
+
+	if written == 0 {
+		return s
+	}
+	b.WriteString(s[written:])
+	return b.String()
+}