mirror of https://github.com/k3s-io/k3s
697 lines
12 KiB
Go
697 lines
12 KiB
Go
package jsonpatch
|
|
|
|
import (
|
|
"bytes"
|
|
"encoding/json"
|
|
"fmt"
|
|
"strconv"
|
|
"strings"
|
|
)
|
|
|
|
const (
|
|
eRaw = iota
|
|
eDoc
|
|
eAry
|
|
)
|
|
|
|
var (
|
|
// SupportNegativeIndices decides whether to support non-standard practice of
|
|
// allowing negative indices to mean indices starting at the end of an array.
|
|
// Default to true.
|
|
SupportNegativeIndices bool = true
|
|
// AccumulatedCopySizeLimit limits the total size increase in bytes caused by
|
|
// "copy" operations in a patch.
|
|
AccumulatedCopySizeLimit int64 = 0
|
|
)
|
|
|
|
type lazyNode struct {
|
|
raw *json.RawMessage
|
|
doc partialDoc
|
|
ary partialArray
|
|
which int
|
|
}
|
|
|
|
type operation map[string]*json.RawMessage
|
|
|
|
// Patch is an ordered collection of operations.
|
|
type Patch []operation
|
|
|
|
type partialDoc map[string]*lazyNode
|
|
type partialArray []*lazyNode
|
|
|
|
type container interface {
|
|
get(key string) (*lazyNode, error)
|
|
set(key string, val *lazyNode) error
|
|
add(key string, val *lazyNode) error
|
|
remove(key string) error
|
|
}
|
|
|
|
func newLazyNode(raw *json.RawMessage) *lazyNode {
|
|
return &lazyNode{raw: raw, doc: nil, ary: nil, which: eRaw}
|
|
}
|
|
|
|
func (n *lazyNode) MarshalJSON() ([]byte, error) {
|
|
switch n.which {
|
|
case eRaw:
|
|
return json.Marshal(n.raw)
|
|
case eDoc:
|
|
return json.Marshal(n.doc)
|
|
case eAry:
|
|
return json.Marshal(n.ary)
|
|
default:
|
|
return nil, fmt.Errorf("Unknown type")
|
|
}
|
|
}
|
|
|
|
func (n *lazyNode) UnmarshalJSON(data []byte) error {
|
|
dest := make(json.RawMessage, len(data))
|
|
copy(dest, data)
|
|
n.raw = &dest
|
|
n.which = eRaw
|
|
return nil
|
|
}
|
|
|
|
func deepCopy(src *lazyNode) (*lazyNode, int, error) {
|
|
if src == nil {
|
|
return nil, 0, nil
|
|
}
|
|
a, err := src.MarshalJSON()
|
|
if err != nil {
|
|
return nil, 0, err
|
|
}
|
|
sz := len(a)
|
|
ra := make(json.RawMessage, sz)
|
|
copy(ra, a)
|
|
return newLazyNode(&ra), sz, nil
|
|
}
|
|
|
|
func (n *lazyNode) intoDoc() (*partialDoc, error) {
|
|
if n.which == eDoc {
|
|
return &n.doc, nil
|
|
}
|
|
|
|
if n.raw == nil {
|
|
return nil, fmt.Errorf("Unable to unmarshal nil pointer as partial document")
|
|
}
|
|
|
|
err := json.Unmarshal(*n.raw, &n.doc)
|
|
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
n.which = eDoc
|
|
return &n.doc, nil
|
|
}
|
|
|
|
func (n *lazyNode) intoAry() (*partialArray, error) {
|
|
if n.which == eAry {
|
|
return &n.ary, nil
|
|
}
|
|
|
|
if n.raw == nil {
|
|
return nil, fmt.Errorf("Unable to unmarshal nil pointer as partial array")
|
|
}
|
|
|
|
err := json.Unmarshal(*n.raw, &n.ary)
|
|
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
n.which = eAry
|
|
return &n.ary, nil
|
|
}
|
|
|
|
func (n *lazyNode) compact() []byte {
|
|
buf := &bytes.Buffer{}
|
|
|
|
if n.raw == nil {
|
|
return nil
|
|
}
|
|
|
|
err := json.Compact(buf, *n.raw)
|
|
|
|
if err != nil {
|
|
return *n.raw
|
|
}
|
|
|
|
return buf.Bytes()
|
|
}
|
|
|
|
func (n *lazyNode) tryDoc() bool {
|
|
if n.raw == nil {
|
|
return false
|
|
}
|
|
|
|
err := json.Unmarshal(*n.raw, &n.doc)
|
|
|
|
if err != nil {
|
|
return false
|
|
}
|
|
|
|
n.which = eDoc
|
|
return true
|
|
}
|
|
|
|
func (n *lazyNode) tryAry() bool {
|
|
if n.raw == nil {
|
|
return false
|
|
}
|
|
|
|
err := json.Unmarshal(*n.raw, &n.ary)
|
|
|
|
if err != nil {
|
|
return false
|
|
}
|
|
|
|
n.which = eAry
|
|
return true
|
|
}
|
|
|
|
func (n *lazyNode) equal(o *lazyNode) bool {
|
|
if n.which == eRaw {
|
|
if !n.tryDoc() && !n.tryAry() {
|
|
if o.which != eRaw {
|
|
return false
|
|
}
|
|
|
|
return bytes.Equal(n.compact(), o.compact())
|
|
}
|
|
}
|
|
|
|
if n.which == eDoc {
|
|
if o.which == eRaw {
|
|
if !o.tryDoc() {
|
|
return false
|
|
}
|
|
}
|
|
|
|
if o.which != eDoc {
|
|
return false
|
|
}
|
|
|
|
for k, v := range n.doc {
|
|
ov, ok := o.doc[k]
|
|
|
|
if !ok {
|
|
return false
|
|
}
|
|
|
|
if v == nil && ov == nil {
|
|
continue
|
|
}
|
|
|
|
if !v.equal(ov) {
|
|
return false
|
|
}
|
|
}
|
|
|
|
return true
|
|
}
|
|
|
|
if o.which != eAry && !o.tryAry() {
|
|
return false
|
|
}
|
|
|
|
if len(n.ary) != len(o.ary) {
|
|
return false
|
|
}
|
|
|
|
for idx, val := range n.ary {
|
|
if !val.equal(o.ary[idx]) {
|
|
return false
|
|
}
|
|
}
|
|
|
|
return true
|
|
}
|
|
|
|
func (o operation) kind() string {
|
|
if obj, ok := o["op"]; ok && obj != nil {
|
|
var op string
|
|
|
|
err := json.Unmarshal(*obj, &op)
|
|
|
|
if err != nil {
|
|
return "unknown"
|
|
}
|
|
|
|
return op
|
|
}
|
|
|
|
return "unknown"
|
|
}
|
|
|
|
func (o operation) path() string {
|
|
if obj, ok := o["path"]; ok && obj != nil {
|
|
var op string
|
|
|
|
err := json.Unmarshal(*obj, &op)
|
|
|
|
if err != nil {
|
|
return "unknown"
|
|
}
|
|
|
|
return op
|
|
}
|
|
|
|
return "unknown"
|
|
}
|
|
|
|
func (o operation) from() string {
|
|
if obj, ok := o["from"]; ok && obj != nil {
|
|
var op string
|
|
|
|
err := json.Unmarshal(*obj, &op)
|
|
|
|
if err != nil {
|
|
return "unknown"
|
|
}
|
|
|
|
return op
|
|
}
|
|
|
|
return "unknown"
|
|
}
|
|
|
|
func (o operation) value() *lazyNode {
|
|
if obj, ok := o["value"]; ok {
|
|
return newLazyNode(obj)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func isArray(buf []byte) bool {
|
|
Loop:
|
|
for _, c := range buf {
|
|
switch c {
|
|
case ' ':
|
|
case '\n':
|
|
case '\t':
|
|
continue
|
|
case '[':
|
|
return true
|
|
default:
|
|
break Loop
|
|
}
|
|
}
|
|
|
|
return false
|
|
}
|
|
|
|
func findObject(pd *container, path string) (container, string) {
|
|
doc := *pd
|
|
|
|
split := strings.Split(path, "/")
|
|
|
|
if len(split) < 2 {
|
|
return nil, ""
|
|
}
|
|
|
|
parts := split[1 : len(split)-1]
|
|
|
|
key := split[len(split)-1]
|
|
|
|
var err error
|
|
|
|
for _, part := range parts {
|
|
|
|
next, ok := doc.get(decodePatchKey(part))
|
|
|
|
if next == nil || ok != nil {
|
|
return nil, ""
|
|
}
|
|
|
|
if isArray(*next.raw) {
|
|
doc, err = next.intoAry()
|
|
|
|
if err != nil {
|
|
return nil, ""
|
|
}
|
|
} else {
|
|
doc, err = next.intoDoc()
|
|
|
|
if err != nil {
|
|
return nil, ""
|
|
}
|
|
}
|
|
}
|
|
|
|
return doc, decodePatchKey(key)
|
|
}
|
|
|
|
func (d *partialDoc) set(key string, val *lazyNode) error {
|
|
(*d)[key] = val
|
|
return nil
|
|
}
|
|
|
|
func (d *partialDoc) add(key string, val *lazyNode) error {
|
|
(*d)[key] = val
|
|
return nil
|
|
}
|
|
|
|
func (d *partialDoc) get(key string) (*lazyNode, error) {
|
|
return (*d)[key], nil
|
|
}
|
|
|
|
func (d *partialDoc) remove(key string) error {
|
|
_, ok := (*d)[key]
|
|
if !ok {
|
|
return fmt.Errorf("Unable to remove nonexistent key: %s", key)
|
|
}
|
|
|
|
delete(*d, key)
|
|
return nil
|
|
}
|
|
|
|
// set should only be used to implement the "replace" operation, so "key" must
|
|
// be an already existing index in "d".
|
|
func (d *partialArray) set(key string, val *lazyNode) error {
|
|
idx, err := strconv.Atoi(key)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
(*d)[idx] = val
|
|
return nil
|
|
}
|
|
|
|
func (d *partialArray) add(key string, val *lazyNode) error {
|
|
if key == "-" {
|
|
*d = append(*d, val)
|
|
return nil
|
|
}
|
|
|
|
idx, err := strconv.Atoi(key)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
sz := len(*d) + 1
|
|
|
|
ary := make([]*lazyNode, sz)
|
|
|
|
cur := *d
|
|
|
|
if idx >= len(ary) {
|
|
return fmt.Errorf("Unable to access invalid index: %d", idx)
|
|
}
|
|
|
|
if SupportNegativeIndices {
|
|
if idx < -len(ary) {
|
|
return fmt.Errorf("Unable to access invalid index: %d", idx)
|
|
}
|
|
|
|
if idx < 0 {
|
|
idx += len(ary)
|
|
}
|
|
}
|
|
|
|
copy(ary[0:idx], cur[0:idx])
|
|
ary[idx] = val
|
|
copy(ary[idx+1:], cur[idx:])
|
|
|
|
*d = ary
|
|
return nil
|
|
}
|
|
|
|
func (d *partialArray) get(key string) (*lazyNode, error) {
|
|
idx, err := strconv.Atoi(key)
|
|
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
if idx >= len(*d) {
|
|
return nil, fmt.Errorf("Unable to access invalid index: %d", idx)
|
|
}
|
|
|
|
return (*d)[idx], nil
|
|
}
|
|
|
|
func (d *partialArray) remove(key string) error {
|
|
idx, err := strconv.Atoi(key)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
cur := *d
|
|
|
|
if idx >= len(cur) {
|
|
return fmt.Errorf("Unable to access invalid index: %d", idx)
|
|
}
|
|
|
|
if SupportNegativeIndices {
|
|
if idx < -len(cur) {
|
|
return fmt.Errorf("Unable to access invalid index: %d", idx)
|
|
}
|
|
|
|
if idx < 0 {
|
|
idx += len(cur)
|
|
}
|
|
}
|
|
|
|
ary := make([]*lazyNode, len(cur)-1)
|
|
|
|
copy(ary[0:idx], cur[0:idx])
|
|
copy(ary[idx:], cur[idx+1:])
|
|
|
|
*d = ary
|
|
return nil
|
|
|
|
}
|
|
|
|
func (p Patch) add(doc *container, op operation) error {
|
|
path := op.path()
|
|
|
|
con, key := findObject(doc, path)
|
|
|
|
if con == nil {
|
|
return fmt.Errorf("jsonpatch add operation does not apply: doc is missing path: \"%s\"", path)
|
|
}
|
|
|
|
return con.add(key, op.value())
|
|
}
|
|
|
|
func (p Patch) remove(doc *container, op operation) error {
|
|
path := op.path()
|
|
|
|
con, key := findObject(doc, path)
|
|
|
|
if con == nil {
|
|
return fmt.Errorf("jsonpatch remove operation does not apply: doc is missing path: \"%s\"", path)
|
|
}
|
|
|
|
return con.remove(key)
|
|
}
|
|
|
|
func (p Patch) replace(doc *container, op operation) error {
|
|
path := op.path()
|
|
|
|
con, key := findObject(doc, path)
|
|
|
|
if con == nil {
|
|
return fmt.Errorf("jsonpatch replace operation does not apply: doc is missing path: %s", path)
|
|
}
|
|
|
|
_, ok := con.get(key)
|
|
if ok != nil {
|
|
return fmt.Errorf("jsonpatch replace operation does not apply: doc is missing key: %s", path)
|
|
}
|
|
|
|
return con.set(key, op.value())
|
|
}
|
|
|
|
func (p Patch) move(doc *container, op operation) error {
|
|
from := op.from()
|
|
|
|
con, key := findObject(doc, from)
|
|
|
|
if con == nil {
|
|
return fmt.Errorf("jsonpatch move operation does not apply: doc is missing from path: %s", from)
|
|
}
|
|
|
|
val, err := con.get(key)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
err = con.remove(key)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
path := op.path()
|
|
|
|
con, key = findObject(doc, path)
|
|
|
|
if con == nil {
|
|
return fmt.Errorf("jsonpatch move operation does not apply: doc is missing destination path: %s", path)
|
|
}
|
|
|
|
return con.add(key, val)
|
|
}
|
|
|
|
func (p Patch) test(doc *container, op operation) error {
|
|
path := op.path()
|
|
|
|
con, key := findObject(doc, path)
|
|
|
|
if con == nil {
|
|
return fmt.Errorf("jsonpatch test operation does not apply: is missing path: %s", path)
|
|
}
|
|
|
|
val, err := con.get(key)
|
|
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if val == nil {
|
|
if op.value().raw == nil {
|
|
return nil
|
|
}
|
|
return fmt.Errorf("Testing value %s failed", path)
|
|
} else if op.value() == nil {
|
|
return fmt.Errorf("Testing value %s failed", path)
|
|
}
|
|
|
|
if val.equal(op.value()) {
|
|
return nil
|
|
}
|
|
|
|
return fmt.Errorf("Testing value %s failed", path)
|
|
}
|
|
|
|
func (p Patch) copy(doc *container, op operation, accumulatedCopySize *int64) error {
|
|
from := op.from()
|
|
|
|
con, key := findObject(doc, from)
|
|
|
|
if con == nil {
|
|
return fmt.Errorf("jsonpatch copy operation does not apply: doc is missing from path: %s", from)
|
|
}
|
|
|
|
val, err := con.get(key)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
path := op.path()
|
|
|
|
con, key = findObject(doc, path)
|
|
|
|
if con == nil {
|
|
return fmt.Errorf("jsonpatch copy operation does not apply: doc is missing destination path: %s", path)
|
|
}
|
|
|
|
valCopy, sz, err := deepCopy(val)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
(*accumulatedCopySize) += int64(sz)
|
|
if AccumulatedCopySizeLimit > 0 && *accumulatedCopySize > AccumulatedCopySizeLimit {
|
|
return NewAccumulatedCopySizeError(AccumulatedCopySizeLimit, *accumulatedCopySize)
|
|
}
|
|
|
|
return con.add(key, valCopy)
|
|
}
|
|
|
|
// Equal indicates if 2 JSON documents have the same structural equality.
|
|
func Equal(a, b []byte) bool {
|
|
ra := make(json.RawMessage, len(a))
|
|
copy(ra, a)
|
|
la := newLazyNode(&ra)
|
|
|
|
rb := make(json.RawMessage, len(b))
|
|
copy(rb, b)
|
|
lb := newLazyNode(&rb)
|
|
|
|
return la.equal(lb)
|
|
}
|
|
|
|
// DecodePatch decodes the passed JSON document as an RFC 6902 patch.
|
|
func DecodePatch(buf []byte) (Patch, error) {
|
|
var p Patch
|
|
|
|
err := json.Unmarshal(buf, &p)
|
|
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return p, nil
|
|
}
|
|
|
|
// Apply mutates a JSON document according to the patch, and returns the new
|
|
// document.
|
|
func (p Patch) Apply(doc []byte) ([]byte, error) {
|
|
return p.ApplyIndent(doc, "")
|
|
}
|
|
|
|
// ApplyIndent mutates a JSON document according to the patch, and returns the new
|
|
// document indented.
|
|
func (p Patch) ApplyIndent(doc []byte, indent string) ([]byte, error) {
|
|
var pd container
|
|
if doc[0] == '[' {
|
|
pd = &partialArray{}
|
|
} else {
|
|
pd = &partialDoc{}
|
|
}
|
|
|
|
err := json.Unmarshal(doc, pd)
|
|
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
err = nil
|
|
|
|
var accumulatedCopySize int64
|
|
|
|
for _, op := range p {
|
|
switch op.kind() {
|
|
case "add":
|
|
err = p.add(&pd, op)
|
|
case "remove":
|
|
err = p.remove(&pd, op)
|
|
case "replace":
|
|
err = p.replace(&pd, op)
|
|
case "move":
|
|
err = p.move(&pd, op)
|
|
case "test":
|
|
err = p.test(&pd, op)
|
|
case "copy":
|
|
err = p.copy(&pd, op, &accumulatedCopySize)
|
|
default:
|
|
err = fmt.Errorf("Unexpected kind: %s", op.kind())
|
|
}
|
|
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
}
|
|
|
|
if indent != "" {
|
|
return json.MarshalIndent(pd, "", indent)
|
|
}
|
|
|
|
return json.Marshal(pd)
|
|
}
|
|
|
|
// From http://tools.ietf.org/html/rfc6901#section-4 :
|
|
//
|
|
// Evaluation of each reference token begins by decoding any escaped
|
|
// character sequence. This is performed by first transforming any
|
|
// occurrence of the sequence '~1' to '/', and then transforming any
|
|
// occurrence of the sequence '~0' to '~'.
|
|
|
|
var (
|
|
rfc6901Decoder = strings.NewReplacer("~1", "/", "~0", "~")
|
|
)
|
|
|
|
func decodePatchKey(k string) string {
|
|
return rfc6901Decoder.Replace(k)
|
|
}
|