99 lines
2.4 KiB
Go
99 lines
2.4 KiB
Go
|
package etreeutils
|
||
|
|
|
||
|
|
import (
|
||
|
|
"sort"
|
||
|
|
"strings"
|
||
|
|
|
||
|
|
"github.com/beevik/etree"
|
||
|
|
)
|
||
|
|
|
||
|
|
// TransformExcC14n transforms the passed element into xml-exc-c14n form.
|
||
|
|
func TransformExcC14n(el *etree.Element, inclusiveNamespacesPrefixList string) error {
|
||
|
|
prefixes := strings.Fields(inclusiveNamespacesPrefixList)
|
||
|
|
prefixSet := make(map[string]struct{}, len(prefixes))
|
||
|
|
|
||
|
|
for _, prefix := range prefixes {
|
||
|
|
prefixSet[prefix] = struct{}{}
|
||
|
|
}
|
||
|
|
|
||
|
|
err := transformExcC14n(DefaultNSContext, EmptyNSContext, el, prefixSet)
|
||
|
|
if err != nil {
|
||
|
|
return err
|
||
|
|
}
|
||
|
|
|
||
|
|
return nil
|
||
|
|
}
|
||
|
|
|
||
|
|
func transformExcC14n(ctx, declared NSContext, el *etree.Element, inclusiveNamespaces map[string]struct{}) error {
|
||
|
|
scope, err := ctx.SubContext(el)
|
||
|
|
if err != nil {
|
||
|
|
return err
|
||
|
|
}
|
||
|
|
|
||
|
|
visiblyUtilizedPrefixes := map[string]struct{}{
|
||
|
|
el.Space: struct{}{},
|
||
|
|
}
|
||
|
|
|
||
|
|
filteredAttrs := []etree.Attr{}
|
||
|
|
|
||
|
|
// Filter out all namespace declarations
|
||
|
|
for _, attr := range el.Attr {
|
||
|
|
switch {
|
||
|
|
case attr.Space == xmlnsPrefix:
|
||
|
|
if _, ok := inclusiveNamespaces[attr.Key]; ok {
|
||
|
|
visiblyUtilizedPrefixes[attr.Key] = struct{}{}
|
||
|
|
}
|
||
|
|
|
||
|
|
case attr.Space == defaultPrefix && attr.Key == xmlnsPrefix:
|
||
|
|
if _, ok := inclusiveNamespaces[defaultPrefix]; ok {
|
||
|
|
visiblyUtilizedPrefixes[defaultPrefix] = struct{}{}
|
||
|
|
}
|
||
|
|
|
||
|
|
default:
|
||
|
|
if attr.Space != defaultPrefix {
|
||
|
|
visiblyUtilizedPrefixes[attr.Space] = struct{}{}
|
||
|
|
}
|
||
|
|
|
||
|
|
filteredAttrs = append(filteredAttrs, attr)
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
el.Attr = filteredAttrs
|
||
|
|
|
||
|
|
declared = declared.Copy()
|
||
|
|
|
||
|
|
// Declare all visibly utilized prefixes that are in-scope but haven't
|
||
|
|
// been declared in the canonicalized form yet. These might have been
|
||
|
|
// declared on this element but then filtered out above, or they might
|
||
|
|
// have been declared on an ancestor (before canonicalization) which
|
||
|
|
// didn't visibly utilize and thus had them removed.
|
||
|
|
for prefix := range visiblyUtilizedPrefixes {
|
||
|
|
// Skip redundant declarations - they have to already have the same
|
||
|
|
// value.
|
||
|
|
if declaredNamespace, ok := declared.prefixes[prefix]; ok {
|
||
|
|
if value, ok := scope.prefixes[prefix]; ok && declaredNamespace == value {
|
||
|
|
continue
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
namespace, err := scope.LookupPrefix(prefix)
|
||
|
|
if err != nil {
|
||
|
|
return err
|
||
|
|
}
|
||
|
|
|
||
|
|
el.Attr = append(el.Attr, declared.declare(prefix, namespace))
|
||
|
|
}
|
||
|
|
|
||
|
|
sort.Sort(SortedAttrs(el.Attr))
|
||
|
|
|
||
|
|
// Transform child elements
|
||
|
|
for _, child := range el.ChildElements() {
|
||
|
|
err := transformExcC14n(scope, declared, child, inclusiveNamespaces)
|
||
|
|
if err != nil {
|
||
|
|
return err
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return nil
|
||
|
|
}
|