Golang Element.SelectAttrValue方法代码示例

func getReferencedXML(reference *etree.Element, inputDoc *etree.Document) (outputDoc *etree.Document, err error) {
	uri := reference.SelectAttrValue("URI", "")
	uri = strings.Replace(uri, "#", "", 1)
	// populate doc with the referenced xml from the Reference URI
	if uri == "" {
		outputDoc = inputDoc
	} else {
		path := fmt.Sprintf(".//[@ID='%s']", uri)
		e := inputDoc.FindElement(path)
		if e != nil {
			outputDoc = etree.NewDocument()
			outputDoc.SetRoot(e.Copy())
		} else {
			// SAML v1.1 Assertions use AssertionID
			path := fmt.Sprintf(".//[@AssertionID='%s']", uri)
			e := inputDoc.FindElement(path)
			if e != nil {
				outputDoc = etree.NewDocument()
				outputDoc.SetRoot(e.Copy())
			}
		}
	}

	if outputDoc == nil {
		return nil, errors.New("signedxml: unable to find refereced xml")
	}

	return outputDoc, nil
}

func processTransform(transform *etree.Element,
	docIn *etree.Document) (docOut *etree.Document, err error) {

	transformAlgoURI := transform.SelectAttrValue("Algorithm", "")
	if transformAlgoURI == "" {
		return nil, errors.New("signedxml: unable to find Algorithm in Transform")
	}

	transformAlgo, ok := CanonicalizationAlgorithms[transformAlgoURI]
	if !ok {
		return nil, fmt.Errorf("signedxml: unable to find matching transform"+
			"algorithm for %s in CanonicalizationAlgorithms", transformAlgoURI)
	}

	var transformContent string

	if transform.ChildElements() != nil {
		tDoc := etree.NewDocument()
		tDoc.SetRoot(transform.Copy())
		transformContent, err = tDoc.WriteToString()
		if err != nil {
			return nil, err
		}
	}

	docString, err := docIn.WriteToString()
	if err != nil {
		return nil, err
	}

	docString, err = transformAlgo.Process(docString, transformContent)
	if err != nil {
		return nil, err
	}

	docOut = etree.NewDocument()
	docOut.ReadFromString(docString)

	return docOut, nil
}

func (e ExclusiveCanonicalization) renderAttributes(node *etree.Element,
	prefixesInScope []string, defaultNS string) (newDefaultNS string,
	newPrefixesInScope []string) {

	currentNS := node.SelectAttrValue("xmlns", defaultNS)
	elementAttributes := []etree.Attr{}
	nsListToRender := make(map[string]string)
	attrListToRender := attributes{}

	// load map with for prefix -> uri lookup
	for _, attr := range node.Attr {
		if attr.Space == "xmlns" {
			e.namespaces[attr.Key] = attr.Value
		}
	}

	// handle the namespace of the node itself
	if node.Space != "" {
		if !contains(prefixesInScope, node.Space) {
			nsListToRender["xmlns:"+node.Space] = e.namespaces[node.Space]
			prefixesInScope = append(prefixesInScope, node.Space)
		}
	} else if defaultNS != currentNS {
		newDefaultNS = currentNS
		elementAttributes = append(elementAttributes,
			etree.Attr{Key: "xmlns", Value: currentNS})
	}

	for _, attr := range node.Attr {
		// include the namespaces if they are in the inclusiveNamespacePrefixList
		if attr.Space == "xmlns" {
			if !contains(prefixesInScope, attr.Key) &&
				contains(e.inclusiveNamespacePrefixList, attr.Key) {

				nsListToRender["xmlns:"+attr.Key] = attr.Value
				prefixesInScope = append(prefixesInScope, attr.Key)
			}
		}

		// include namespaces for qualfied attributes
		if attr.Space != "" &&
			attr.Space != "xmlns" &&
			!contains(prefixesInScope, attr.Space) {

			nsListToRender["xmlns:"+attr.Space] = e.namespaces[attr.Space]
			prefixesInScope = append(prefixesInScope, attr.Space)
		}

		// inclued all non-namespace attributes
		if attr.Space != "xmlns" && attr.Key != "xmlns" {
			attrListToRender = append(attrListToRender,
				attribute{
					prefix: attr.Space,
					uri:    e.namespaces[attr.Space],
					key:    attr.Key,
					value:  attr.Value,
				})
		}
	}

	// sort and add the namespace attributes first
	sortedNSList := getSortedNamespaces(nsListToRender)
	elementAttributes = append(elementAttributes, sortedNSList...)
	// then sort and add the non-namespace attributes
	sortedAttributes := getSortedAttributes(attrListToRender)
	elementAttributes = append(elementAttributes, sortedAttributes...)
	// replace the nodes attributes with the sorted copy
	node.Attr = elementAttributes
	return currentNS, prefixesInScope
}