With this PR gowsdl will be enabled to support SOAP MTOM

Makefile

@@ -1,6 +1,6 @@
 GHACCOUNT := hooklift
 NAME := gowsdl
-VERSION := v0.2.1
+VERSION := v0.5.0
 
 include common.mk
 

soap/MMAEncoder.go

@@ -0,0 +1,150 @@
+package soap
+
+import (
+	"bytes"
+	"encoding/xml"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"mime"
+	"mime/multipart"
+	"net/textproto"
+	"strings"
+)
+
+const mmaContentType string = `multipart/related; start="<soaprequest@gowsdl.lib>"; type="text/xml"; boundary="%s"`
+
+type mmaEncoder struct {
+	writer      *multipart.Writer
+	attachments []MIMEMultipartAttachment
+}
+
+type mmaDecoder struct {
+	reader *multipart.Reader
+}
+
+func newMmaEncoder(w io.Writer, attachments []MIMEMultipartAttachment) *mmaEncoder {
+	return &mmaEncoder{
+		writer:      multipart.NewWriter(w),
+		attachments: attachments,
+	}
+}
+
+func newMmaDecoder(r io.Reader, boundary string) *mmaDecoder {
+	return &mmaDecoder{
+		reader: multipart.NewReader(r, boundary),
+	}
+}
+
+func (e *mmaEncoder) Encode(v interface{}) error {
+	var err error
+	var soapPartWriter io.Writer
+
+	// 1. write SOAP envelope part
+	headers := make(textproto.MIMEHeader)
+	headers.Set("Content-Type", `text/xml;charset=UTF-8`)
+	headers.Set("Content-Transfer-Encoding", "8bit")
+	headers.Set("Content-ID", "<soaprequest@gowsdl.lib>")
+	if soapPartWriter, err = e.writer.CreatePart(headers); err != nil {
+		return err
+	}
+	xmlEncoder := xml.NewEncoder(soapPartWriter)
+	if err := xmlEncoder.Encode(v); err != nil {
+		return err
+	}
+
+	// 2. write attachments parts
+	for _, attachment := range e.attachments {
+		attHeader := make(textproto.MIMEHeader)
+		attHeader.Set("Content-Type", fmt.Sprintf("application/octet-stream; name=%s", attachment.Name))
+		attHeader.Set("Content-Transfer-Encoding", "binary")
+		attHeader.Set("Content-ID", fmt.Sprintf("<%s>", attachment.Name))
+		attHeader.Set("Content-Disposition",
+			fmt.Sprintf("attachment; name=\"%s\"; filename=\"%s\"", attachment.Name, attachment.Name))
+		var attachmentPartWriter io.Writer
+		attachmentPartWriter, err := e.writer.CreatePart(attHeader)
+		if err != nil {
+			return err
+		}
+		_, err = io.Copy(attachmentPartWriter, bytes.NewReader(attachment.Data))
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func (e *mmaEncoder) Flush() error {
+	return e.writer.Close()
+}
+
+func (e *mmaEncoder) Boundary() string {
+	return e.writer.Boundary()
+}
+
+func getMmaHeader(contentType string) (string, error) {
+	mediaType, params, err := mime.ParseMediaType(contentType)
+	if err != nil {
+		return "", err
+	}
+
+	if strings.HasPrefix(mediaType, "multipart/") {
+		boundary, ok := params["boundary"]
+		if !ok || boundary == "" {
+			return "", fmt.Errorf("invalid multipart boundary: %s", boundary)
+		}
+
+		startInfo, ok := params["start"]
+		if !ok || startInfo != "<soaprequest@gowsdl.lib>" {
+			return "", fmt.Errorf(`expected param start="<soaprequest@gowsdl.lib>", got %s`, startInfo)
+		}
+		return boundary, nil
+	}
+
+	return "", nil
+}
+
+func (d *mmaDecoder) Decode(v interface{}) error {
+	soapEnvResp := v.(*SOAPEnvelopeResponse)
+	attachments := make([]MIMEMultipartAttachment, 0)
+	for {
+		p, err := d.reader.NextPart()
+		if err != nil {
+			if err == io.EOF {
+				break
+			}
+			return err
+		}
+		contentType := p.Header.Get("Content-Type")
+		if contentType == "text/xml;charset=UTF-8" {
+			// decode SOAP part
+			err := xml.NewDecoder(p).Decode(v)
+			if err != nil {
+				return err
+			}
+		} else {
+			// decode attachment parts
+			contentID := p.Header.Get("Content-Id")
+			if contentID == "" {
+				return errors.New("Invalid multipart content ID")
+			}
+			content, err := ioutil.ReadAll(p)
+			if err != nil {
+				return err
+			}
+
+			contentID = strings.Trim(contentID, "<>")
+			attachments = append(attachments, MIMEMultipartAttachment{
+				Name: contentID,
+				Data: content,
+			})
+		}
+	}
+	if len(attachments) > 0 {
+		soapEnvResp.Attachments = attachments
+	}
+
+	return nil
+}

soap/MTOMEncoder.go

@@ -31,7 +31,7 @@ type xopPlaceholder struct {
 	Href string `xml:"href,attr"`
 }
 
-// NewBinary allocate a new Binary backed by the given byte slice
+// NewBinary allocate a new Binary backed by the given byte slice, an auto-generated packageID and no MTOM-usage
 func NewBinary(v []byte) *Binary {
 	return &Binary{&v, "application/octet-stream", "", false}
 }
@@ -41,6 +41,18 @@ func (b *Binary) Bytes() []byte {
 	return *b.content
 }
 
+// SetUseMTOM activates the XOP transformation of binaries in MTOM requests
+func (b *Binary) SetUseMTOM(useMTOM bool) *Binary {
+	b.useMTOM = useMTOM
+	return b
+}
+
+// SetPackageID sets and overrides the default auto-generated package ID to be used for the multipart binary
+func (b *Binary) SetPackageID(packageID string) *Binary {
+	b.packageID = packageID
+	return b
+}
+
 // SetContentType sets the content type the content will be transmitted as multipart
 func (b *Binary) SetContentType(contentType string) *Binary {
 	b.contentType = contentType
@@ -55,7 +67,9 @@ func (b *Binary) ContentType() string {
 // MarshalXML implements the xml.Marshaler interface to encode a Binary to XML
 func (b *Binary) MarshalXML(enc *xml.Encoder, start xml.StartElement) error {
 	if b.useMTOM {
-		b.packageID = fmt.Sprintf("%d", rand.Int())
+		if b.packageID == "" {
+			b.packageID = fmt.Sprintf("%d", rand.Int())
+		}
 		return enc.EncodeElement(struct {
 			Include *xopPlaceholder `xml:"http://www.w3.org/2004/08/xop/include Include"`
 		}{