Beispiel #1
0
// Apply attempts to apply the changes described by Delta onto latest,
// returning an error if the changes cannot be applied cleanly.
// IsConflicting will be true if the changes overlap, otherwise a
// generic error will be returned.
func (d *Delta) Apply(latest []byte) ([]byte, error) {
	base, err := yaml.ToJSON(latest)
	if err != nil {
		return nil, err
	}
	changes, err := jsonpatch.CreateMergePatch(d.original, base)
	if err != nil {
		return nil, err
	}
	diff1 := make(map[string]interface{})
	if err := json.Unmarshal(d.edit, &diff1); err != nil {
		return nil, err
	}
	diff2 := make(map[string]interface{})
	if err := json.Unmarshal(changes, &diff2); err != nil {
		return nil, err
	}
	for _, fn := range d.preconditions {
		hold1, _ := fn(diff1)
		hold2, _ := fn(diff2)
		if !hold1 || !hold2 {
			return nil, ErrPreconditionFailed
		}
	}

	glog.V(6).Infof("Testing for conflict between:\n%s\n%s", string(d.edit), string(changes))
	hasConflicts, err := strategicpatch.HasConflicts(diff1, diff2)
	if err != nil {
		return nil, err
	}
	if hasConflicts {
		return nil, ErrConflict
	}

	return jsonpatch.MergePatch(base, d.edit)
}
// patchResource divides PatchResource for easier unit testing
func patchResource(ctx api.Context, timeout time.Duration, versionedObj runtime.Object, patcher rest.Patcher, name string, patchType api.PatchType, patchJS []byte, namer ScopeNamer, codec runtime.Codec) (runtime.Object, error) {
	namespace := api.NamespaceValue(ctx)

	original, err := patcher.Get(ctx, name)
	if err != nil {
		return nil, err
	}

	originalObjJS, err := codec.Encode(original)
	if err != nil {
		return nil, err
	}
	originalPatchedObjJS, err := getPatchedJS(patchType, originalObjJS, patchJS, versionedObj)
	if err != nil {
		return nil, err
	}

	objToUpdate := patcher.New()
	if err := codec.DecodeInto(originalPatchedObjJS, objToUpdate); err != nil {
		return nil, err
	}
	if err := checkName(objToUpdate, name, namespace, namer); err != nil {
		return nil, err
	}

	return finishRequest(timeout, func() (runtime.Object, error) {
		// update should never create as previous get would fail
		updateObject, _, updateErr := patcher.Update(ctx, objToUpdate)
		for i := 0; i < MaxPatchConflicts && (errors.IsConflict(updateErr)); i++ {

			// 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
			// 5. retry the update
			currentObject, err := patcher.Get(ctx, name)
			if err != nil {
				return nil, err
			}
			currentObjectJS, err := codec.Encode(currentObject)
			if err != nil {
				return nil, err
			}

			currentPatch, err := strategicpatch.CreateStrategicMergePatch(originalObjJS, currentObjectJS, patcher.New())
			if err != nil {
				return nil, err
			}
			originalPatch, err := strategicpatch.CreateStrategicMergePatch(originalObjJS, originalPatchedObjJS, patcher.New())
			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 {
				return updateObject, updateErr
			}

			newlyPatchedObjJS, err := getPatchedJS(api.StrategicMergePatchType, currentObjectJS, originalPatch, versionedObj)
			if err != nil {
				return nil, err
			}
			if err := codec.DecodeInto(newlyPatchedObjJS, objToUpdate); err != nil {
				return nil, err
			}

			updateObject, _, updateErr = patcher.Update(ctx, objToUpdate)
		}

		return updateObject, updateErr
	})
}
// 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, strategicpatch.SMPatchVersionLatest)
			if err != nil {
				return nil, err
			}
			originalPatch, err := strategicpatch.CreateStrategicMergePatch(originalObjJS, originalPatchedObjJS, versionedObj, strategicpatch.SMPatchVersionLatest)
			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
	})
}
Beispiel #4
0
// patchResource divides PatchResource for easier unit testing
func patchResource(
	ctx request.Context,
	admit updateAdmissionFunc,
	timeout time.Duration,
	versionedObj runtime.Object,
	patcher rest.Patcher,
	name string,
	patchType types.PatchType,
	patchJS []byte,
	namer ScopeNamer,
	copier runtime.ObjectCopier,
	resource schema.GroupVersionResource,
	codec runtime.Codec,
) (runtime.Object, error) {

	namespace := request.NamespaceValue(ctx)

	var (
		originalObjJS        []byte
		originalPatchedObjJS []byte
		originalObjMap       map[string]interface{}
		originalPatchMap     map[string]interface{}
		lastConflictErr      error
	)

	// applyPatch is called every time GuaranteedUpdate asks for the updated object,
	// and is given the currently persisted object as input.
	applyPatch := func(_ request.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 originalObjJS == nil && originalObjMap == nil:
			// first time through,
			// 1. apply the patch
			// 2. save the original and patched to detect whether there were conflicting changes on retries

			objToUpdate := patcher.New()

			// For performance reasons, in case of strategicpatch, we avoid json
			// marshaling and unmarshaling and operate just on map[string]interface{}.
			// In case of other patch types, we still have to operate on JSON
			// representations.
			switch patchType {
			case types.JSONPatchType, types.MergePatchType:
				originalJS, patchedJS, err := patchObjectJSON(patchType, codec, currentObject, patchJS, objToUpdate, versionedObj)
				if err != nil {
					return nil, err
				}
				originalObjJS, originalPatchedObjJS = originalJS, patchedJS
			case types.StrategicMergePatchType:
				originalMap, patchMap, err := strategicPatchObject(codec, currentObject, patchJS, objToUpdate, versionedObj)
				if err != nil {
					return nil, err
				}
				originalObjMap, originalPatchMap = originalMap, patchMap
			}
			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

			// TODO: This should be one-step conversion that doesn't require
			// json marshaling and unmarshaling once #39017 is fixed.
			data, err := runtime.Encode(codec, currentObject)
			if err != nil {
				return nil, err
			}
			currentObjMap := make(map[string]interface{})
			if err := json.Unmarshal(data, &currentObjMap); err != nil {
				return nil, err
			}

			var currentPatchMap map[string]interface{}
			if originalObjMap != nil {
				var err error
				currentPatchMap, err = strategicpatch.CreateTwoWayMergeMapPatch(originalObjMap, currentObjMap, versionedObj)
				if err != nil {
					return nil, err
				}
			} else {
				if originalPatchMap == nil {
					// Compute original patch, if we already didn't do this in previous retries.
					originalPatch, err := strategicpatch.CreateTwoWayMergePatch(originalObjJS, originalPatchedObjJS, versionedObj)
					if err != nil {
						return nil, err
					}
					originalPatchMap = make(map[string]interface{})
					if err := json.Unmarshal(originalPatch, &originalPatchMap); err != nil {
						return nil, err
					}
				}
				// Compute current patch.
				currentObjJS, err := runtime.Encode(codec, currentObject)
				if err != nil {
					return nil, err
				}
				currentPatch, err := strategicpatch.CreateTwoWayMergePatch(originalObjJS, currentObjJS, versionedObj)
				if err != nil {
					return nil, err
				}
				currentPatchMap = make(map[string]interface{})
				if err := json.Unmarshal(currentPatch, &currentPatchMap); err != nil {
					return nil, err
				}
			}

			hasConflicts, err := strategicpatch.HasConflicts(originalPatchMap, currentPatchMap)
			if err != nil {
				return nil, err
			}
			if hasConflicts {
				if glog.V(4) {
					diff1, _ := json.Marshal(currentPatchMap)
					diff2, _ := json.Marshal(originalPatchMap)
					glog.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)
			}

			objToUpdate := patcher.New()
			if err := applyPatchToObject(codec, currentObjMap, originalPatchMap, objToUpdate, versionedObj); 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 request.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 < maxRetryWhenPatchConflicts && (errors.IsConflict(updateErr)); i++ {
			lastConflictErr = updateErr
			updateObject, _, updateErr = patcher.Update(ctx, name, updatedObjectInfo)
		}
		return updateObject, updateErr
	})
}