rabbah commented on a change in pull request #4314: CosmosDB Cache Invalidation Service URL: https://github.com/apache/incubator-openwhisk/pull/4314#discussion_r267391138
########## File path: core/cosmosdb/cache-invalidator/README.md ########## @@ -0,0 +1,67 @@ +<!-- +# +# Licensed to the Apache Software Foundation (ASF) under one or more +# contributor license agreements. See the NOTICE file distributed with +# this work for additional information regarding copyright ownership. +# The ASF licenses this file to You under the Apache License, Version 2.0 +# (the "License"); you may not use this file except in compliance with +# the License. You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +# +--> +# OpenWhisk Cache Invalidator Service + +This service performs cache invalidation in OpenWhisk cluster to enable cache event propagation in multi region setups. + +## Design + +OpenWhisk cluster uses a Kafka topic `cacheInvalidation` to communicate changes to any cached entity. Messages on this +topic are of the form + +```json +{"instanceId":"controller0","key":{"mainId":"guest/hello"}} +``` + +When deploying multiple seprate cluster of OpenWhisk which do not share same Kafka instance we would need a way to Review comment: When deploying multiple seprate cluster of OpenWhisk which do not share same Kafka instance we would need a way to propagate the cache change event across cluster. -> When deploying OpenWhisk across multiple nodes which do not share a common Kafka instance, we need a way to propagate the cache-change events across the cluster. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services
