// patchResource divides PatchResource for easier unit testing
func patchResource(
ctx api.Context,
admit updateAdmissionFunc,
timeout time.Duration,
versionedObj runtime.Object,
patcher rest.Patcher,
name string,
patchType api.PatchType,
patchJS []byte,
namer ScopeNamer,
copier runtime.ObjectCopier,
resource unversioned.GroupVersionResource,
codec runtime.Codec,
) (runtime.Object, error) {
namespace := api.NamespaceValue(ctx)
var (
originalObjJS []byte
originalPatchedObjJS []byte
lastConflictErr error
)
// applyPatch is called every time GuaranteedUpdate asks for the updated object,
// and is given the currently persisted object as input.
applyPatch := func(_ api.Context, _, currentObject runtime.Object) (runtime.Object, error) {
// Make sure we actually have a persisted currentObject
if hasUID, err := hasUID(currentObject); err != nil {
return nil, err
} else if !hasUID {
return nil, errors.NewNotFound(resource.GroupResource(), name)
}
switch {
case len(originalObjJS) == 0 || len(originalPatchedObjJS) == 0:
// first time through,
// 1. apply the patch
// 2. save the originalJS and patchedJS to detect whether there were conflicting changes on retries
if js, err := runtime.Encode(codec, currentObject); err != nil {
return nil, err
} else {
originalObjJS = js
}
if js, err := getPatchedJS(patchType, originalObjJS, patchJS, versionedObj); err != nil {
return nil, err
} else {
originalPatchedObjJS = js
}
objToUpdate := patcher.New()
if err := runtime.DecodeInto(codec, originalPatchedObjJS, objToUpdate); err != nil {
return nil, err
}
if err := checkName(objToUpdate, name, namespace, namer); err != nil {
return nil, err
}
return objToUpdate, nil
default:
// on a conflict,
// 1. build a strategic merge patch from originalJS and the patchedJS. Different patch types can
// be specified, but a strategic merge patch should be expressive enough handle them. Build the
// patch with this type to handle those cases.
// 2. build a strategic merge patch from originalJS and the currentJS
// 3. ensure no conflicts between the two patches
// 4. apply the #1 patch to the currentJS object
currentObjectJS, err := runtime.Encode(codec, currentObject)
if err != nil {
return nil, err
}
currentPatch, err := strategicpatch.CreateStrategicMergePatch(originalObjJS, currentObjectJS, versionedObj)
if err != nil {
return nil, err
}
originalPatch, err := strategicpatch.CreateStrategicMergePatch(originalObjJS, originalPatchedObjJS, versionedObj)
if err != nil {
return nil, err
}
diff1 := make(map[string]interface{})
if err := json.Unmarshal(originalPatch, &diff1); err != nil {
return nil, err
}
diff2 := make(map[string]interface{})
if err := json.Unmarshal(currentPatch, &diff2); err != nil {
return nil, err
}
hasConflicts, err := strategicpatch.HasConflicts(diff1, diff2)
if err != nil {
return nil, err
}
if hasConflicts {
glog.V(4).Infof("patchResource failed for resource %s, because there is a meaningful conflict.\n diff1=%v\n, diff2=%v\n", name, diff1, diff2)
// Return the last conflict error we got if we have one
if lastConflictErr != nil {
return nil, lastConflictErr
}
// Otherwise manufacture one of our own
return nil, errors.NewConflict(resource.GroupResource(), name, nil)
}
newlyPatchedObjJS, err := getPatchedJS(api.StrategicMergePatchType, currentObjectJS, originalPatch, versionedObj)
if err != nil {
return nil, err
}
objToUpdate := patcher.New()
if err := runtime.DecodeInto(codec, newlyPatchedObjJS, objToUpdate); err != nil {
return nil, err
}
return objToUpdate, nil
}
}
// applyAdmission is called every time GuaranteedUpdate asks for the updated object,
// and is given the currently persisted object and the patched object as input.
applyAdmission := func(ctx api.Context, patchedObject runtime.Object, currentObject runtime.Object) (runtime.Object, error) {
return patchedObject, admit(patchedObject, currentObject)
}
updatedObjectInfo := rest.DefaultUpdatedObjectInfo(nil, copier, applyPatch, applyAdmission)
return finishRequest(timeout, func() (runtime.Object, error) {
updateObject, _, updateErr := patcher.Update(ctx, name, updatedObjectInfo)
for i := 0; i < MaxPatchConflicts && (errors.IsConflict(updateErr)); i++ {
lastConflictErr = updateErr
updateObject, _, updateErr = patcher.Update(ctx, name, updatedObjectInfo)
}
return updateObject, updateErr
})
}
func (tc *patchTestCase) Run(t *testing.T) {
t.Logf("Starting test %s", tc.name)
namespace := tc.startingPod.Namespace
name := tc.startingPod.Name
codec := testapi.Default.Codec()
admit := tc.admit
if admit == nil {
admit = func(updatedObject runtime.Object, currentObject runtime.Object) error {
return nil
}
}
testPatcher := &testPatcher{}
testPatcher.t = t
testPatcher.startingPod = tc.startingPod
testPatcher.updatePod = tc.updatePod
ctx := api.NewDefaultContext()
ctx = api.WithNamespace(ctx, namespace)
namer := &testNamer{namespace, name}
copier := runtime.ObjectCopier(api.Scheme)
resource := unversioned.GroupVersionResource{Group: "", Version: "v1", Resource: "pods"}
versionedObj, err := api.Scheme.ConvertToVersion(&api.Pod{}, unversioned.GroupVersion{Version: "v1"})
if err != nil {
t.Errorf("%s: unexpected error: %v", tc.name, err)
return
}
for _, patchType := range []api.PatchType{api.JSONPatchType, api.MergePatchType, api.StrategicMergePatchType} {
// TODO SUPPORT THIS!
if patchType == api.JSONPatchType {
continue
}
t.Logf("Working with patchType %v", patchType)
originalObjJS, err := runtime.Encode(codec, tc.startingPod)
if err != nil {
t.Errorf("%s: unexpected error: %v", tc.name, err)
return
}
changedJS, err := runtime.Encode(codec, tc.changedPod)
if err != nil {
t.Errorf("%s: unexpected error: %v", tc.name, err)
return
}
patch := []byte{}
switch patchType {
case api.JSONPatchType:
continue
case api.StrategicMergePatchType:
patch, err = strategicpatch.CreateStrategicMergePatch(originalObjJS, changedJS, versionedObj)
if err != nil {
t.Errorf("%s: unexpected error: %v", tc.name, err)
return
}
case api.MergePatchType:
patch, err = jsonpatch.CreateMergePatch(originalObjJS, changedJS)
if err != nil {
t.Errorf("%s: unexpected error: %v", tc.name, err)
return
}
}
resultObj, err := patchResource(ctx, admit, 1*time.Second, versionedObj, testPatcher, name, patchType, patch, namer, copier, resource, codec)
if len(tc.expectedError) != 0 {
if err == nil || err.Error() != tc.expectedError {
t.Errorf("%s: expected error %v, but got %v", tc.name, tc.expectedError, err)
return
}
} else {
if err != nil {
t.Errorf("%s: unexpected error: %v", tc.name, err)
return
}
}
if tc.expectedPod == nil {
if resultObj != nil {
t.Errorf("%s: unexpected result: %v", tc.name, resultObj)
}
return
}
resultPod := resultObj.(*api.Pod)
// roundtrip to get defaulting
expectedJS, err := runtime.Encode(codec, tc.expectedPod)
if err != nil {
t.Errorf("%s: unexpected error: %v", tc.name, err)
return
}
expectedObj, err := runtime.Decode(codec, expectedJS)
if err != nil {
t.Errorf("%s: unexpected error: %v", tc.name, err)
return
}
reallyExpectedPod := expectedObj.(*api.Pod)
if !reflect.DeepEqual(*reallyExpectedPod, *resultPod) {
t.Errorf("%s mismatch: %v\n", tc.name, diff.ObjectGoPrintDiff(reallyExpectedPod, resultPod))
return
}
}
}