Update Azure SDK (#4985)

vendor/github.com/Azure/azure-sdk-for-go/storage/util.go

@@ -12,9 +12,15 @@ import (
 	"net/http"
 	"net/url"
 	"reflect"
+	"strconv"
+	"strings"
 	"time"
 )
 
+var (
+	fixedTime = time.Date(2050, time.December, 20, 21, 55, 0, 0, time.FixedZone("GMT", -6))
+)
+
 func (c Client) computeHmac256(message string) string {
 	h := hmac.New(sha256.New, c.accountKey)
 	h.Write([]byte(message))
@@ -76,10 +82,118 @@ func headersFromStruct(v interface{}) map[string]string {
 	value := reflect.ValueOf(v)
 	for i := 0; i < value.NumField(); i++ {
 		key := value.Type().Field(i).Tag.Get("header")
-		val := value.Field(i).String()
-		if key != "" && val != "" {
-			headers[key] = val
+		if key != "" {
+			reflectedValue := reflect.Indirect(value.Field(i))
+			var val string
+			if reflectedValue.IsValid() {
+				switch reflectedValue.Type() {
+				case reflect.TypeOf(fixedTime):
+					val = timeRfc1123Formatted(reflectedValue.Interface().(time.Time))
+				case reflect.TypeOf(uint64(0)), reflect.TypeOf(uint(0)):
+					val = strconv.FormatUint(reflectedValue.Uint(), 10)
+				case reflect.TypeOf(int(0)):
+					val = strconv.FormatInt(reflectedValue.Int(), 10)
+				default:
+					val = reflectedValue.String()
+				}
+			}
+			if val != "" {
+				headers[key] = val
+			}
 		}
 	}
 	return headers
 }
+
+// merges extraHeaders into headers and returns headers
+func mergeHeaders(headers, extraHeaders map[string]string) map[string]string {
+	for k, v := range extraHeaders {
+		headers[k] = v
+	}
+	return headers
+}
+
+func addToHeaders(h map[string]string, key, value string) map[string]string {
+	if value != "" {
+		h[key] = value
+	}
+	return h
+}
+
+func addTimeToHeaders(h map[string]string, key string, value *time.Time) map[string]string {
+	if value != nil {
+		h = addToHeaders(h, key, timeRfc1123Formatted(*value))
+	}
+	return h
+}
+
+func addTimeout(params url.Values, timeout uint) url.Values {
+	if timeout > 0 {
+		params.Add("timeout", fmt.Sprintf("%v", timeout))
+	}
+	return params
+}
+
+func addSnapshot(params url.Values, snapshot *time.Time) url.Values {
+	if snapshot != nil {
+		params.Add("snapshot", snapshot.Format("2006-01-02T15:04:05.0000000Z"))
+	}
+	return params
+}
+
+func getTimeFromHeaders(h http.Header, key string) (*time.Time, error) {
+	var out time.Time
+	var err error
+	outStr := h.Get(key)
+	if outStr != "" {
+		out, err = time.Parse(time.RFC1123, outStr)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return &out, nil
+}
+
+// TimeRFC1123 is an alias for time.Time needed for custom Unmarshalling
+type TimeRFC1123 time.Time
+
+// UnmarshalXML is a custom unmarshaller that overrides the default time unmarshal which uses a different time layout.
+func (t *TimeRFC1123) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
+	var value string
+	d.DecodeElement(&value, &start)
+	parse, err := time.Parse(time.RFC1123, value)
+	if err != nil {
+		return err
+	}
+	*t = TimeRFC1123(parse)
+	return nil
+}
+
+// returns a map of custom metadata values from the specified HTTP header
+func getMetadataFromHeaders(header http.Header) map[string]string {
+	metadata := make(map[string]string)
+	for k, v := range header {
+		// Can't trust CanonicalHeaderKey() to munge case
+		// reliably. "_" is allowed in identifiers:
+		// https://msdn.microsoft.com/en-us/library/azure/dd179414.aspx
+		// https://msdn.microsoft.com/library/aa664670(VS.71).aspx
+		// http://tools.ietf.org/html/rfc7230#section-3.2
+		// ...but "_" is considered invalid by
+		// CanonicalMIMEHeaderKey in
+		// https://golang.org/src/net/textproto/reader.go?s=14615:14659#L542
+		// so k can be "X-Ms-Meta-Lol" or "x-ms-meta-lol_rofl".
+		k = strings.ToLower(k)
+		if len(v) == 0 || !strings.HasPrefix(k, strings.ToLower(userDefinedMetadataHeaderPrefix)) {
+			continue
+		}
+		// metadata["lol"] = content of the last X-Ms-Meta-Lol header
+		k = k[len(userDefinedMetadataHeaderPrefix):]
+		metadata[k] = v[len(v)-1]
+	}
+
+	if len(metadata) == 0 {
+		return nil
+	}
+
+	return metadata
+}