Golang Patcher.Get方法代码示例

// 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 returns a function that will handle a resource patch
// TODO: Eventually PatchResource should just use GuaranteedUpdate and this routine should be a bit cleaner
func PatchResource(r rest.Patcher, scope RequestScope, typer runtime.ObjectTyper, admit admission.Interface, converter runtime.ObjectConvertor) restful.RouteFunction {
	return func(req *restful.Request, res *restful.Response) {
		w := res.ResponseWriter

		// TODO: we either want to remove timeout or document it (if we
		// document, move timeout out of this function and declare it in
		// api_installer)
		timeout := parseTimeout(req.Request.URL.Query().Get("timeout"))

		namespace, name, err := scope.Namer.Name(req)
		if err != nil {
			errorJSON(err, scope.Codec, w)
			return
		}

		obj := r.New()
		ctx := scope.ContextFunc(req)
		ctx = api.WithNamespace(ctx, namespace)

		// PATCH requires same permission as UPDATE
		if admit.Handles(admission.Update) {
			userInfo, _ := api.UserFrom(ctx)

			err = admit.Admit(admission.NewAttributesRecord(obj, scope.Kind, namespace, name, scope.Resource, scope.Subresource, admission.Update, userInfo))
			if err != nil {
				errorJSON(err, scope.Codec, w)
				return
			}
		}

		versionedObj, err := converter.ConvertToVersion(obj, scope.APIVersion)
		if err != nil {
			errorJSON(err, scope.Codec, w)
			return
		}

		original, err := r.Get(ctx, name)
		if err != nil {
			errorJSON(err, scope.Codec, w)
			return
		}

		originalObjJS, err := scope.Codec.Encode(original)
		if err != nil {
			errorJSON(err, scope.Codec, w)
			return
		}
		patchJS, err := readBody(req.Request)
		if err != nil {
			errorJSON(err, scope.Codec, w)
			return
		}
		contentType := req.HeaderParameter("Content-Type")
		patchedObjJS, err := getPatchedJS(contentType, originalObjJS, patchJS, versionedObj)
		if err != nil {
			errorJSON(err, scope.Codec, w)
			return
		}

		if err := scope.Codec.DecodeInto(patchedObjJS, obj); err != nil {
			errorJSON(err, scope.Codec, w)
			return
		}
		if err := checkName(obj, name, namespace, scope.Namer); err != nil {
			errorJSON(err, scope.Codec, w)
			return
		}

		result, err := finishRequest(timeout, func() (runtime.Object, error) {
			// update should never create as previous get would fail
			obj, _, err := r.Update(ctx, obj)
			return obj, err
		})
		if err != nil {
			errorJSON(err, scope.Codec, w)
			return
		}

		if err := setSelfLink(result, req, scope.Namer); err != nil {
			errorJSON(err, scope.Codec, w)
			return
		}

		write(http.StatusOK, scope.APIVersion, scope.Codec, result, w, req.Request)
	}
}