Add XML payload support

Fixes #238

vendor/github.com/clbanning/mxj/leafnode.go

@@ -0,0 +1,112 @@
+package mxj
+
+// leafnode.go - return leaf nodes with paths and values for the Map
+// inspired by: https://groups.google.com/forum/#!topic/golang-nuts/3JhuVKRuBbw
+
+import (
+	"strconv"
+	"strings"
+)
+
+const (
+	NoAttributes = true // suppress LeafNode values that are attributes
+)
+
+// LeafNode - a terminal path value in a Map.
+// For XML Map values it represents an attribute or simple element value  - of type
+// string unless Map was created using Cast flag. For JSON Map values it represents
+// a string, numeric, boolean, or null value.
+type LeafNode struct {
+	Path  string      // a dot-notation representation of the path with array subscripting
+	Value interface{} // the value at the path termination
+}
+
+// LeafNodes - returns an array of all LeafNode values for the Map.
+// The option no_attr argument suppresses attribute values (keys with prepended hyphen, '-')
+// as well as the "#text" key for the associated simple element value.
+//
+// PrependAttrWithHypen(false) will result in attributes having .attr-name as 
+// terminal node in 'path' while the path for the element value, itself, will be 
+// the base path w/o "#text". 
+//
+// LeafUseDotNotation(true) causes list members to be identified using ".N" syntax
+// rather than "[N]" syntax.
+func (mv Map) LeafNodes(no_attr ...bool) []LeafNode {
+	var a bool
+	if len(no_attr) == 1 {
+		a = no_attr[0]
+	}
+
+	l := make([]LeafNode, 0)
+	getLeafNodes("", "", map[string]interface{}(mv), &l, a)
+	return l
+}
+
+func getLeafNodes(path, node string, mv interface{}, l *[]LeafNode, noattr bool) {
+	// if stripping attributes, then also strip "#text" key
+	if !noattr || node != "#text" {
+		if path != "" && node[:1] != "[" {
+			path += "."
+		}
+		path += node
+	}
+	switch mv.(type) {
+	case map[string]interface{}:
+		for k, v := range mv.(map[string]interface{}) {
+			// if noattr && k[:1] == "-" {
+			if noattr && len(attrPrefix) > 0 && strings.Index(k, attrPrefix) == 0 {
+				continue
+			}
+			getLeafNodes(path, k, v, l, noattr)
+		}
+	case []interface{}:
+		for i, v := range mv.([]interface{}) {
+			if useDotNotation {
+				getLeafNodes(path, strconv.Itoa(i), v, l, noattr)
+			} else {
+				getLeafNodes(path, "["+strconv.Itoa(i)+"]", v, l, noattr)
+			}
+		}
+	default:
+		// can't walk any further, so create leaf
+		n := LeafNode{path, mv}
+		*l = append(*l, n)
+	}
+}
+
+// LeafPaths - all paths that terminate in LeafNode values.
+func (mv Map) LeafPaths(no_attr ...bool) []string {
+	ln := mv.LeafNodes()
+	ss := make([]string, len(ln))
+	for i := 0; i < len(ln); i++ {
+		ss[i] = ln[i].Path
+	}
+	return ss
+}
+
+// LeafValues - all terminal values in the Map.
+func (mv Map) LeafValues(no_attr ...bool) []interface{} {
+	ln := mv.LeafNodes()
+	vv := make([]interface{}, len(ln))
+	for i := 0; i < len(ln); i++ {
+		vv[i] = ln[i].Value
+	}
+	return vv
+}
+
+// ====================== utilities ======================
+
+// https://groups.google.com/forum/#!topic/golang-nuts/pj0C5IrZk4I
+var useDotNotation bool
+
+// LeafUseDotNotation sets a flag that list members in LeafNode paths
+// should be identified using ".N" syntax rather than the default "[N]"
+// syntax.  Calling LeafUseDotNotation with no arguments toggles the 
+// flag on/off; otherwise, the argument sets the flag value 'true'/'false'.
+func LeafUseDotNotation(b ...bool) {
+	if len(b) == 0 {
+		useDotNotation = !useDotNotation
+		return
+	}
+	useDotNotation = b[0]
+}