Added basic support for WSS Security header: new structs WSSSecurityH…

…eader, WSSUsernameToken and its child structs WSSUsername and WSSPassword.

XML namespace problems are dealt with by using vania-pooh's workaround:  golang/go#9519 (comment)

Convenience function "NewWSSSecurityHeader" to ease header creation (the header is not automatically added to the SOAP client).

"SetHeader" method is kept for compatibility. There is a new "AddHeader" method to add headers to the SOAP call. There is now support for several headers instead of only one.

Cosmetic changes in header_tmpl.go to sort import names alphabetically.

Sample code:

   ...
   hdr := myservice.NewWSSSecurityHeader("sampleuser", "samplepassword", "1")  // "1" is for 'mustUnderstand' attribute; empty if not specified
   myserviceClient.AddHeader(hdr)
   ...

header_tmpl.go

@@ -8,15 +8,15 @@ var headerTmpl = `
 package {{.}}
 
 import (
+	"bytes"
+	"crypto/tls"
 	"encoding/xml"
-	"time"
- 	"bytes"
- 	"crypto/tls"
- 	"encoding/xml"
- 	"io/ioutil"
-	"net/http"
+	"io/ioutil"
 	"log"
+	"math/rand"
 	"net"
+	"net/http"
+	"time"
 
 	{{/*range .Imports*/}}
 		{{/*.*/}}

operations_tmpl.go

@@ -22,8 +22,13 @@ var opsTmpl = `
 		}
 	}
 
+	func (service *{{$portType}}) AddHeader(header interface{}) {
+		service.client.AddHeader(header)
+	}
+
+	// Backwards-compatible function: use AddHeader instead
 	func (service *{{$portType}}) SetHeader(header interface{}) {
-		service.client.SetHeader(header)
+		service.client.AddHeader(header)
 	}
 
 	{{range .Operations}}

soap_tmpl.go

@@ -19,8 +19,8 @@ type SOAPEnvelope struct {
 
 type SOAPHeader struct {
 	XMLName xml.Name ` + "`" + `xml:"http://schemas.xmlsoap.org/soap/envelope/ Header"` + "`" + `
-
-	Header interface{}
+	
+	Items []interface{} ` + "`" + `xml:",omitempty"` + "`" + `
 }
 
 type SOAPBody struct {
@@ -39,16 +39,97 @@ type SOAPFault struct {
 	Detail string ` + "`" + `xml:"detail,omitempty"` + "`" + `
 }
 
+const (
+	// Predefined WSS namespaces to be used in
+	WssNsWSSE string = "http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd"
+	WssNsWSU  string = "http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd"
+	WssNsType string = "http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-username-token-profile-1.0#PasswordText"
+)
+
+type WSSSecurityHeader struct {
+	XMLName   xml.Name ` + "`" + `xml:"http://schemas.xmlsoap.org/soap/envelope/ wsse:Security"` + "`" + `
+	XmlNSWsse string   ` + "`" + `xml:"xmlns:wsse,attr"` + "`" + `
+	
+	MustUnderstand string ` + "`" + `xml:"mustUnderstand,attr,omitempty"` + "`" + `
+
+	Token *WSSUsernameToken ` + "`" + `xml:",omitempty"` + "`" + `
+}
+
+type WSSUsernameToken struct {
+	XMLName   xml.Name ` + "`" + `xml:"wsse:UsernameToken"` + "`" + `
+	XmlNSWsu  string   ` + "`" + `xml:"xmlns:wsu,attr"` + "`" + `
+	XmlNSWsse string   ` + "`" + `xml:"xmlns:wsse,attr"` + "`" + `
+
+	Id string ` + "`" + `xml:"wsu:Id,attr,omitempty"` + "`" + `
+
+	Username *WSSUsername ` + "`" + `xml:",omitempty"` + "`" + `
+	Password *WSSPassword ` + "`" + `xml:",omitempty"` + "`" + `
+}
+
+type WSSUsername struct {
+	XMLName   xml.Name ` + "`" + `xml:"wsse:Username"` + "`" + `
+	XmlNSWsse string   ` + "`" + `xml:"xmlns:wsse,attr"` + "`" + `
+
+	Data string ` + "`" + `xml:",chardata"` + "`" + `
+}
+
+type WSSPassword struct {
+	XMLName   xml.Name ` + "`" + `xml:"wsse:Password"` + "`" + `
+	XmlNSWsse string   ` + "`" + `xml:"xmlns:wsse,attr"` + "`" + `
+	XmlNSType string   ` + "`" + `xml:"Type,attr"` + "`" + `
+
+	Data string ` + "`" + `xml:",chardata"` + "`" + `
+}
+
 type BasicAuth struct {
-	Login string
+	Login    string
 	Password string
 }
 
 type SOAPClient struct {
-	url string
-	tls bool
-	auth *BasicAuth
-	header interface{}
+	url     string
+	tls     bool
+	auth    *BasicAuth
+	headers []interface{}
+}
+
+// **********
+// Accepted solution from http://stackoverflow.com/questions/22892120/how-to-generate-a-random-string-of-a-fixed-length-in-golang
+// Author: Icza - http://stackoverflow.com/users/1705598/icza
+
+const (
+	letterBytes   = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"
+	letterIdxBits = 6                    // 6 bits to represent a letter index
+	letterIdxMask = 1<<letterIdxBits - 1 // All 1-bits, as many as letterIdxBits
+	letterIdxMax  = 63 / letterIdxBits   // # of letter indices fitting in 63 bits
+)
+
+func randStringBytesMaskImprSrc(n int) string {
+	src := rand.NewSource(time.Now().UnixNano())
+	b := make([]byte, n)
+	// A src.Int63() generates 63 random bits, enough for letterIdxMax characters!
+	for i, cache, remain := n-1, src.Int63(), letterIdxMax; i >= 0; {
+		if remain == 0 {
+			cache, remain = src.Int63(), letterIdxMax
+		}
+		if idx := int(cache & letterIdxMask); idx < len(letterBytes) {
+			b[i] = letterBytes[idx]
+			i--
+		}
+		cache >>= letterIdxBits
+		remain--
+	}
+	return string(b)
+}
+
+// **********
+
+func NewWSSSecurityHeader(user, pass, mustUnderstand string) *WSSSecurityHeader {
+	hdr := &WSSSecurityHeader{XmlNSWsse: WssNsWSSE, MustUnderstand: mustUnderstand}
+	hdr.Token = &WSSUsernameToken{XmlNSWsu: WssNsWSU, XmlNSWsse: WssNsWSSE, Id: "UsernameToken-" + randStringBytesMaskImprSrc(9)}
+	hdr.Token.Username = &WSSUsername{XmlNSWsse: WssNsWSSE, Data: user}
+	hdr.Token.Password = &WSSPassword{XmlNSWsse: WssNsWSSE, XmlNSType: WssNsType, Data: pass}
+	return hdr
 }
 
 func (b *SOAPBody) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
@@ -113,15 +194,17 @@ func NewSOAPClient(url string, tls bool, auth *BasicAuth) *SOAPClient {
 	}
 }
 
-func (s *SOAPClient) SetHeader(header interface{}) {
-	s.header = header
+func (s *SOAPClient) AddHeader(header interface{}) {
+	s.headers = append(s.headers, header)
 }
 
 func (s *SOAPClient) Call(soapAction string, request, response interface{}) error {
 	envelope := SOAPEnvelope{}
 
-	if s.header != nil {
-		envelope.Header = &SOAPHeader{Header: s.header}
+	if s.headers != nil && len(s.headers) > 0 {
+		soapHeader := &SOAPHeader{Items: make([]interface{}, len(s.headers))}
+		copy(soapHeader.Items, s.headers)
+		envelope.Header = soapHeader
 	}
 
 	envelope.Body.Content = request
@@ -149,10 +232,8 @@ func (s *SOAPClient) Call(soapAction string, request, response interface{}) erro
 	}
 
 	req.Header.Add("Content-Type", "text/xml; charset=\"utf-8\"")
-	if soapAction != "" {
-		req.Header.Add("SOAPAction", soapAction)
-	}
-
+	req.Header.Add("SOAPAction", soapAction)
+	
 	req.Header.Set("User-Agent", "gowsdl/0.1")
 	req.Close = true