Exemplo n.º 1
0
// As the Search function, but passing a VariableScope that can be used to reolve variable
// names or registered function references in the XPath being evaluated.
func (xmlNode *XmlNode) SearchWithVariables(data interface{}, v xpath.VariableScope) (result []Node, err error) {
	switch data := data.(type) {
	default:
		err = ERR_UNDEFINED_SEARCH_PARAM
	case string:
		if xpathExpr := xpath.Compile(data); xpathExpr != nil {
			defer xpathExpr.Free()
			result, err = xmlNode.SearchWithVariables(xpathExpr, v)
		} else {
			err = errors.New("cannot compile xpath: " + data)
		}
	case []byte:
		result, err = xmlNode.SearchWithVariables(string(data), v)
	case *xpath.Expression:
		xpathCtx := xmlNode.Document.DocXPathCtx()
		xpathCtx.SetResolver(v)
		nodePtrs, err := xpathCtx.EvaluateAsNodeset(unsafe.Pointer(xmlNode.Ptr), data)
		if nodePtrs == nil || err != nil {
			return nil, err
		}
		for _, nodePtr := range nodePtrs {
			result = append(result, NewNode(nodePtr, xmlNode.Document))
		}
	}
	return
}
Exemplo n.º 2
0
func httpGetXpath(link, xpathStr string) (string, error) {
	buf, err := httpGet(link)
	if err != nil {
		return "", err
	}

	doc, err := gokogiri.ParseHtml(buf)
	defer doc.Free()
	if err != nil {
		return "", err
	}
	if doc.Root() == nil {
		return "", errElementNotFound
	}

	xpath := xpath.Compile(xpathStr)
	defer xpath.Free()
	sr, err := doc.Root().Search(xpath)
	if err != nil {
		return "", err
	}

	if len(sr) > 0 {
		return sr[0].InnerHtml(), nil
	}

	return "", errElementNotFound
}
Exemplo n.º 3
0
func (context *ExecutionContext) EvalXPath(xmlNode xml.Node, data interface{}) (result interface{}, err error) {
	switch data := data.(type) {
	case string:
		if xpathExpr := xpath.Compile(data); xpathExpr != nil {
			defer xpathExpr.Free()
			result, err = context.EvalXPath(xmlNode, xpathExpr)
		} else {
			err = errors.New("cannot compile xpath: " + data)
		}
	case []byte:
		result, err = context.EvalXPath(xmlNode, string(data))
	case *xpath.Expression:
		xpathCtx := context.XPathContext
		xpathCtx.SetResolver(context)
		err := xpathCtx.Evaluate(xmlNode.NodePtr(), data)
		if err != nil {
			return nil, err
		}
		rt := xpathCtx.ReturnType()
		switch rt {
		case xpath.XPATH_NODESET, xpath.XPATH_XSLT_TREE:
			nodePtrs, err := xpathCtx.ResultAsNodeset()
			if err != nil {
				return nil, err
			}
			var output []xml.Node
			for _, nodePtr := range nodePtrs {
				output = append(output, xml.NewNode(nodePtr, xmlNode.MyDocument()))
			}
			result = output
		case xpath.XPATH_NUMBER:
			result, err = xpathCtx.ResultAsNumber()
		case xpath.XPATH_BOOLEAN:
			result, err = xpathCtx.ResultAsBoolean()
		default:
			result, err = xpathCtx.ResultAsString()
		}
	default:
		err = errors.New("Strange type passed to ExecutionContext.EvalXPath")
	}
	return
}
Exemplo n.º 4
0
// Applying a variable node is calculating its value.
func (i *Variable) Apply(node xml.Node, context *ExecutionContext) {
	scope := i.Node.Attr("select")
	// if @select
	if scope != "" {
		e := xpath.Compile(scope)
		var err error
		context.RegisterXPathNamespaces(i.Node)
		i.Value, err = context.EvalXPath(node, e)
		if err != nil {
			fmt.Println("Error evaluating variable", i.Name, err)
		}
		//fmt.Println("VARIABLE SELECT", i.Name, i.Value)
		return
	}

	if len(i.Children) == 0 {
		//fmt.Println("VARIABLE NIL", name, i.Value)
		i.Value = nil
		return
	}

	// if multiple children, return nodeset
	curOutput := context.OutputNode
	context.OutputNode = context.Output.CreateElementNode("RVT")
	context.PushStack()
	for _, c := range i.Children {
		c.Apply(node, context)
		switch v := c.(type) {
		case *Variable:
			_ = context.DeclareLocalVariable(v.Name, "", v)
		}
	}
	context.PopStack()
	i.Value = nil
	var outNodes xml.Nodeset
	for cur := context.OutputNode.FirstChild(); cur != nil; cur = cur.NextSibling() {
		outNodes = append(outNodes, cur)
	}
	i.Value = outNodes
	context.OutputNode = curOutput
	//fmt.Println("VARIABLE NODES", name, i.Value)
}
Exemplo n.º 5
0
// Evaluate an XPath and return a result of the appropriate type.
// If a non-nil VariableScope is provided, any variables or functions present
// in the xpath will be resolved.
//
// If the result is a nodeset (or the empty nodeset), a nodeset will be returned.
//
// If the result is a number, a float64 will be returned.
//
// If the result is a boolean, a bool will be returned.
//
// In any other cases, the result will be coerced to a string.
func (xmlNode *XmlNode) EvalXPath(data interface{}, v xpath.VariableScope) (result interface{}, err error) {
	switch data := data.(type) {
	case string:
		if xpathExpr := xpath.Compile(data); xpathExpr != nil {
			defer xpathExpr.Free()
			result, err = xmlNode.EvalXPath(xpathExpr, v)
		} else {
			err = errors.New("cannot compile xpath: " + data)
		}
	case []byte:
		result, err = xmlNode.EvalXPath(string(data), v)
	case *xpath.Expression:
		xpathCtx := xmlNode.Document.DocXPathCtx()
		xpathCtx.SetResolver(v)
		err := xpathCtx.Evaluate(unsafe.Pointer(xmlNode.Ptr), data)
		if err != nil {
			return nil, err
		}
		rt := xpathCtx.ReturnType()
		switch rt {
		case xpath.XPATH_NODESET, xpath.XPATH_XSLT_TREE:
			nodePtrs, err := xpathCtx.ResultAsNodeset()
			if err != nil {
				return nil, err
			}
			var output []Node
			for _, nodePtr := range nodePtrs {
				output = append(output, NewNode(nodePtr, xmlNode.Document))
			}
			result = output
		case xpath.XPATH_NUMBER:
			result, _ = xpathCtx.ResultAsNumber()
		case xpath.XPATH_BOOLEAN:
			result, _ = xpathCtx.ResultAsBoolean()
		default:
			result, _ = xpathCtx.ResultAsString()
		}
	default:
		err = ERR_UNDEFINED_SEARCH_PARAM
	}
	return
}
Exemplo n.º 6
0
// Evaluate an XPath and coerce the result to a boolean according to the
// XPath rules. In the presence of an error, this function will return false
// even if the expression cannot actually be evaluated.
//
// In most cases you are better advised to call EvalXPath; this function is
// intended for packages that implement XML standards and that are fully aware
// of the consequences of suppressing a compilation error.
//
// If a non-nil VariableScope is provided, any variables or registered functions present
// in the xpath will be resolved.
func (xmlNode *XmlNode) EvalXPathAsBoolean(data interface{}, v xpath.VariableScope) (result bool) {
	switch data := data.(type) {
	case string:
		if xpathExpr := xpath.Compile(data); xpathExpr != nil {
			defer xpathExpr.Free()
			result = xmlNode.EvalXPathAsBoolean(xpathExpr, v)
		} else {
			//err = errors.New("cannot compile xpath: " + data)
		}
	case []byte:
		result = xmlNode.EvalXPathAsBoolean(string(data), v)
	case *xpath.Expression:
		xpathCtx := xmlNode.Document.DocXPathCtx()
		xpathCtx.SetResolver(v)
		err := xpathCtx.Evaluate(unsafe.Pointer(xmlNode.Ptr), data)
		if err != nil {
			return false
		}
		result, _ = xpathCtx.ResultAsBoolean()
	default:
		//err = ERR_UNDEFINED_SEARCH_PARAM
	}
	return
}
Exemplo n.º 7
0
// Returns true if the node matches the pattern
func (m *CompiledMatch) EvalMatch(node xml.Node, mode string, context *ExecutionContext) bool {
	cur := node
	//false if wrong mode
	// #all is an XSLT 2.0 feature
	if m.Template != nil && mode != m.Template.Mode && m.Template.Mode != "#all" {
		return false
	}

	for i, step := range m.Steps {
		switch step.Op {
		case OP_END:
			return true
		case OP_ROOT:
			if cur.NodeType() != xml.XML_DOCUMENT_NODE {
				return false
			}
		case OP_ELEM:
			if cur.NodeType() != xml.XML_ELEMENT_NODE {
				return false
			}
			if step.Value != cur.Name() && step.Value != "*" {
				return false
			}
		case OP_NS:
			uri := ""
			// m.Template.Node
			if m.Template != nil {
				uri = context.LookupNamespace(step.Value, m.Template.Node)
			} else {
				uri = context.LookupNamespace(step.Value, nil)
			}
			if uri != cur.Namespace() {
				return false
			}
		case OP_ATTR:
			if cur.NodeType() != xml.XML_ATTRIBUTE_NODE {
				return false
			}
			if step.Value != cur.Name() && step.Value != "*" {
				return false
			}
		case OP_TEXT:
			if cur.NodeType() != xml.XML_TEXT_NODE && cur.NodeType() != xml.XML_CDATA_SECTION_NODE {
				return false
			}
		case OP_COMMENT:
			if cur.NodeType() != xml.XML_COMMENT_NODE {
				return false
			}
		case OP_ALL:
			if cur.NodeType() != xml.XML_ELEMENT_NODE {
				return false
			}
		case OP_PI:
			if cur.NodeType() != xml.XML_PI_NODE {
				return false
			}
		case OP_NODE:
			switch cur.NodeType() {
			case xml.XML_ELEMENT_NODE, xml.XML_CDATA_SECTION_NODE, xml.XML_TEXT_NODE, xml.XML_COMMENT_NODE, xml.XML_PI_NODE:
				// matches any of these node types
			default:
				return false
			}
		case OP_PARENT:
			cur = cur.Parent()
			if cur == nil {
				return false
			}
		case OP_ANCESTOR:
			next := m.Steps[i+1]
			if next.Op != OP_ELEM {
				return false
			}
			for {
				cur = cur.Parent()
				if cur == nil {
					return false
				}
				if next.Value == cur.Name() {
					break
				}
			}
		case OP_PREDICATE:
			// see test REC/5.2-16
			// see test REC/5.2-22
			evalFull := true
			if context != nil {

				prev := m.Steps[i-1]
				if prev.Op == OP_PREDICATE {
					prev = m.Steps[i-2]
				}
				if prev.Op == OP_ELEM || prev.Op == OP_ALL {
					parent := cur.Parent()
					sibs := context.ChildrenOf(parent)
					var clen, pos int
					for _, n := range sibs {
						if n.NodePtr() == cur.NodePtr() {
							pos = clen + 1
							clen = clen + 1
						} else {
							if n.NodeType() == xml.XML_ELEMENT_NODE {
								if n.Name() == cur.Name() || prev.Op == OP_ALL {
									clen = clen + 1
								}
							}
						}
					}
					if step.Value == "last()" {
						if pos != clen {
							return false
						}
					}
					//eval predicate should do special number handling
					postest, err := strconv.Atoi(step.Value)
					if err == nil {
						if pos != postest {
							return false
						}
					}
					opos, olen := context.XPathContext.GetContextPosition()
					context.XPathContext.SetContextPosition(pos, clen)
					result := cur.EvalXPathAsBoolean(step.Value, context)
					context.XPathContext.SetContextPosition(opos, olen)
					if result == false {
						return false
					}
					evalFull = false
				}
			}
			if evalFull {
				//if we made it this far, fall back to the more expensive option of evaluating
				// the entire pattern globally
				//TODO: cache results on first run for given document
				xp := m.pattern
				if m.pattern[0] != '/' {
					xp = "//" + m.pattern
				}
				e := xpath.Compile(xp)
				o, err := node.Search(e)
				if err != nil {
					//fmt.Println("ERROR",err)
				}
				for _, n := range o {
					if cur.NodePtr() == n.NodePtr() {
						return true
					}
				}
				return false
			}

		case OP_ID:
			//TODO: fix lexer to only put literal inside step value
			val := strings.Trim(step.Value, "()\"'")
			id := cur.MyDocument().NodeById(val)
			if id == nil || node.NodePtr() != id.NodePtr() {
				return false
			}
		case OP_KEY:
			//  TODO: make this robust
			if context != nil {
				val := strings.Trim(step.Value, "()")
				v := strings.Split(val, ",")
				keyname := strings.Trim(v[0], "\"'")
				keyval := strings.Trim(v[1], "\"'")
				key, _ := context.Style.Keys[keyname]
				if key != nil {
					o, _ := key.nodes[keyval]
					for _, n := range o {
						if cur.NodePtr() == n.NodePtr() {
							return true
						}
					}
				}
			}
			return false
		default:
			return false
		}
	}
	//in theory, OP_END means we never reach here
	// in practice, we can generate match patterns
	// that are missing OP_END due to how we handle OP_OR
	return true
}
Exemplo n.º 8
0
// Evaluate an instruction and generate output nodes
func (i *XsltInstruction) Apply(node xml.Node, context *ExecutionContext) {
	//push context if children to apply!
	switch i.Name {
	case "apply-templates":
		scope := i.Node.Attr("select")
		mode := i.Node.Attr("mode")
		// #current is a 2.0 keyword
		if mode != context.Mode && mode != "#current" {
			context.Mode = mode
		}
		// TODO: determine with-params at compile time
		var params []*Variable
		for _, cur := range i.Children {
			switch p := cur.(type) {
			case *Variable:
				if IsXsltName(p.Node, "with-param") {
					p.Apply(node, context)
					params = append(params, p)
				}
			}
		}
		// By default, scope is children of current node
		if scope == "" {
			children := context.ChildrenOf(node)
			if i.sorting != nil {
				i.Sort(children, context)
			}
			total := len(children)
			oldpos, oldtotal := context.XPathContext.GetContextPosition()
			oldcurr := context.Current
			for i, cur := range children {
				context.XPathContext.SetContextPosition(i+1, total)
				//processNode will update Context.Current whenever a template is invoked
				context.Style.processNode(cur, context, params)
			}
			context.XPathContext.SetContextPosition(oldpos, oldtotal)
			context.Current = oldcurr
			return
		}
		context.RegisterXPathNamespaces(i.Node)
		e := xpath.Compile(scope)
		// TODO: ensure we apply strip-space if required
		nodes, err := context.EvalXPathAsNodeset(node, e)
		if err != nil {
			fmt.Println("apply-templates @select", err)
		}
		if i.sorting != nil {
			i.Sort(nodes, context)
		}
		total := len(nodes)
		oldpos, oldtotal := context.XPathContext.GetContextPosition()
		oldcurr := context.Current
		for i, cur := range nodes {
			context.XPathContext.SetContextPosition(i+1, total)
			context.Style.processNode(cur, context, params)
		}
		context.XPathContext.SetContextPosition(oldpos, oldtotal)
		context.Current = oldcurr
	case "number":
		i.numbering(node, context)

	case "text":
		disableEscaping := i.Node.Attr("disable-output-escaping") == "yes"

		content := i.Node.Content()
		//don't bother creating a text node for an empty string
		if content != "" {
			r := context.Output.CreateTextNode(content)
			if disableEscaping {
				r.DisableOutputEscaping()
			}
			context.OutputNode.AddChild(r)
		}

	case "call-template":
		name := i.Node.Attr("name")
		t, ok := context.Style.NamedTemplates[name]
		if ok && t != nil {
			// TODO: determine with-params at compile time
			var params []*Variable
			for _, cur := range i.Children {
				switch p := cur.(type) {
				case *Variable:
					if IsXsltName(p.Node, "with-param") {
						p.Apply(node, context)
						params = append(params, p)
					}
				}
			}
			t.Apply(node, context, params)
		}

	case "element":
		ename := i.Node.Attr("name")
		if strings.ContainsRune(ename, '{') {
			ename = evalAVT(ename, node, context)
		}
		r := context.Output.CreateElementNode(ename)
		ns := i.Node.Attr("namespace")
		if strings.ContainsRune(ns, '{') {
			ns = evalAVT(ns, node, context)
		}
		if ns != "" {
			//TODO: search through namespaces in-scope
			// not just top-level stylesheet mappings
			prefix, _ := context.Style.NamespaceMapping[ns]
			r.SetNamespace(prefix, ns)
		} else {
			// if no namespace specified, use the default namespace
			// in scope at this point in the stylesheet
			defaultNS := context.DefaultNamespace(i.Node)
			if defaultNS != "" {
				r.SetNamespace("", defaultNS)
			}
		}
		context.OutputNode.AddChild(r)
		context.DeclareStylesheetNamespacesIfRoot(r)
		old := context.OutputNode
		context.OutputNode = r

		attsets := i.Node.Attr("use-attribute-sets")
		if attsets != "" {
			asets := strings.Fields(attsets)
			for _, attsetname := range asets {
				a, _ := context.Style.AttributeSets[attsetname]
				if a != nil {
					a.Apply(node, context)
				}
			}
		}
		for _, c := range i.Children {
			c.Apply(node, context)
		}
		context.OutputNode = old

	case "comment":
		val, _ := i.evalChildrenAsText(node, context)
		r := context.Output.CreateCommentNode(val)
		context.OutputNode.AddChild(r)

	case "processing-instruction":
		name := i.Node.Attr("name")
		val, _ := i.evalChildrenAsText(node, context)
		//TODO: it is an error if val contains "?>"
		r := context.Output.CreatePINode(name, val)
		context.OutputNode.AddChild(r)

	case "attribute":
		aname := i.Node.Attr("name")
		if strings.ContainsRune(aname, '{') {
			aname = evalAVT(aname, node, context)
		}
		ahref := i.Node.Attr("namespace")
		if strings.ContainsRune(ahref, '{') {
			ahref = evalAVT(ahref, node, context)
		}
		val, _ := i.evalChildrenAsText(node, context)
		if ahref == "" {
			context.OutputNode.SetAttr(aname, val)
		} else {
			decl := context.OutputNode.DeclaredNamespaces()
			dfound := false
			for _, d := range decl {
				if ahref == d.Uri {
					dfound = true
					break
				}
			}
			if !dfound && ahref != XML_NAMESPACE {
				//TODO: increment val of generated prefix
				context.OutputNode.DeclareNamespace("ns_1", ahref)
			}
			//if a QName, we ignore the prefix when setting namespace
			if strings.Contains(aname, ":") {
				aname = aname[strings.Index(aname, ":")+1:]
			}
			context.OutputNode.SetNsAttr(ahref, aname, val)
		}
		//context.OutputNode.AddChild(a)

	case "value-of":
		e := xpath.Compile(i.Node.Attr("select"))
		disableEscaping := i.Node.Attr("disable-output-escaping") == "yes"

		context.RegisterXPathNamespaces(i.Node)
		content, _ := context.EvalXPathAsString(node, e)
		//don't bother creating a text node for an empty string
		if content != "" {
			if context.UseCDataSection(context.OutputNode) {
				olddata := context.OutputNode.LastChild()
				if olddata == nil || olddata.(*xml.CDataNode) == nil {
					r := context.Output.CreateCDataNode(content)
					context.OutputNode.AddChild(r)
				} else {
					r := context.Output.CreateCDataNode(olddata.Content() + content)
					context.OutputNode.AddChild(r)
					olddata.Remove()
				}
			} else {
				r := context.Output.CreateTextNode(content)
				if disableEscaping {
					r.DisableOutputEscaping()
				}
				context.OutputNode.AddChild(r)
			}
		}
	case "when":
	case "if":
		e := xpath.Compile(i.Node.Attr("test"))
		if context.EvalXPathAsBoolean(node, e) {
			for _, c := range i.Children {
				c.Apply(node, context)
			}
		}
	case "attribute-set":
		for _, c := range i.Children {
			c.Apply(node, context)
		}
		othersets := i.Node.Attr("use-attribute-sets")
		if othersets != "" {
			asets := strings.Fields(othersets)
			for _, attsetname := range asets {
				a := context.Style.LookupAttributeSet(attsetname)
				if a != nil {
					a.Apply(node, context)
				}
			}
		}
	case "fallback":
		for _, c := range i.Children {
			c.Apply(node, context)
		}
	case "otherwise":
		for _, c := range i.Children {
			c.Apply(node, context)
		}

	case "choose":
		for _, c := range i.Children {
			inst := c.(*XsltInstruction)
			if inst.Node.Name() == "when" {
				xp := xpath.Compile(inst.Node.Attr("test"))
				if context.EvalXPathAsBoolean(node, xp) {
					for _, wc := range inst.Children {
						wc.Apply(node, context)
					}
					break
				}
			} else {
				inst.Apply(node, context)
			}
		}
	case "copy":
		//i.copyToOutput(cur, context, false)
		switch node.NodeType() {
		case xml.XML_TEXT_NODE:
			if context.UseCDataSection(context.OutputNode) {
				r := context.Output.CreateCDataNode(node.Content())
				context.OutputNode.AddChild(r)
			} else {
				r := context.Output.CreateTextNode(node.Content())
				context.OutputNode.AddChild(r)
			}
		case xml.XML_ATTRIBUTE_NODE:
			aname := node.Name()
			ahref := node.Namespace()
			val := node.Content()
			if ahref == "" {
				context.OutputNode.SetAttr(aname, val)
			} else {
				context.OutputNode.SetNsAttr(ahref, aname, val)
			}
		case xml.XML_COMMENT_NODE:
			r := context.Output.CreateCommentNode(node.Content())
			context.OutputNode.AddChild(r)
		case xml.XML_PI_NODE:
			name := node.Name()
			r := context.Output.CreatePINode(name, node.Content())
			context.OutputNode.AddChild(r)
		case xml.XML_ELEMENT_NODE:
			aname := node.Name()
			r := context.Output.CreateElementNode(aname)
			context.OutputNode.AddChild(r)
			ns := node.Namespace()
			if ns != "" {
				//TODO: search through namespaces in-scope
				prefix, _ := context.Style.NamespaceMapping[ns]
				r.SetNamespace(prefix, ns)
			}

			//copy namespace declarations
			for _, decl := range node.DeclaredNamespaces() {
				r.DeclareNamespace(decl.Prefix, decl.Uri)
			}

			old := context.OutputNode
			context.OutputNode = r

			attsets := i.Node.Attr("use-attribute-sets")
			if attsets != "" {
				asets := strings.Fields(attsets)
				for _, attsetname := range asets {
					a := context.Style.LookupAttributeSet(attsetname)
					if a != nil {
						a.Apply(node, context)
					}
				}
			}
			for _, c := range i.Children {
				c.Apply(node, context)
			}
			context.OutputNode = old
		}
	case "for-each":
		scope := i.Node.Attr("select")
		e := xpath.Compile(scope)
		context.RegisterXPathNamespaces(i.Node)
		nodes, _ := context.EvalXPathAsNodeset(node, e)
		if i.sorting != nil {
			i.Sort(nodes, context)
		}
		total := len(nodes)
		old_curr := context.Current
		for j, cur := range nodes {
			context.PushStack()
			context.XPathContext.SetContextPosition(j+1, total)
			context.Current = cur
			for _, c := range i.Children {
				c.Apply(cur, context)
				switch v := c.(type) {
				case *Variable:
					_ = context.DeclareLocalVariable(v.Name, "", v)
				}
			}
			context.PopStack()
		}
		context.Current = old_curr
	case "copy-of":
		scope := i.Node.Attr("select")
		e := xpath.Compile(scope)
		context.RegisterXPathNamespaces(i.Node)
		nodes, _ := context.EvalXPathAsNodeset(node, e)
		total := len(nodes)
		for j, cur := range nodes {
			context.XPathContext.SetContextPosition(j+1, total)
			i.copyToOutput(cur, context, true)
		}

	case "message":
		val, _ := i.evalChildrenAsText(node, context)
		terminate := i.Node.Attr("terminate")
		if terminate == "yes" {
			//TODO: fixup error flow to terminate more gracefully
			panic(val)
		} else {
			fmt.Println(val)
		}
	case "apply-imports":
		fmt.Println("TODO handle xsl:apply-imports instruction")
	default:
		hasFallback := false
		for _, c := range i.Children {
			switch v := c.(type) {
			case *XsltInstruction:
				if v.Name == "fallback" {
					c.Apply(node, context)
					hasFallback = true
					break
				}
			}
		}
		if !hasFallback {
			fmt.Println("UNKNOWN instruction ", i.Name)
		}
	}
}