diff --git a/README.md b/README.md index 288e46d6..d6638953 100644 --- a/README.md +++ b/README.md @@ -77,7 +77,7 @@ provides, and how to deploy it. Next we need to deploy the module. There is a deployment descriptor in `target/DeploymentDescriptor.json`. It tells Okapi to start the module on 'localhost'. -Make sure Kafka is up and running on 9092 port before deployment. +****Make sure Kafka is up and running before deployment and pass all the required environment variables.**** Deploy it via Okapi discovery: @@ -99,7 +99,7 @@ curl -w '\n' -X POST -D - \ ``` ## Environment variables -Pubsub requires kafka to be running, and to ensure it can connect and interact with kafka the following environment variable must be specified on deployment: +****Pubsub requires kafka to be running, and to ensure it can connect and interact with kafka the following environment variable must be specified on deployment:**** ``` { "name": "KAFKA_HOST", @@ -114,7 +114,7 @@ Pubsub requires kafka to be running, and to ensure it can connect and interact w "value": "http://10.0.2.15:9130" } ``` -There are two additional parameters required for pubsub to create topics in kafka - number of partitions and replication factor. +****There are two additional parameters required for pubsub to create topics in kafka - number of partitions and replication factor.**** The replication factor controls how many servers will replicate each message that is written. If replication factor set to 3 then up to 2 servers can fail before access to the data will be lost. The partition count controls how many logs the topic will be sharded into. @@ -130,15 +130,15 @@ The partition count controls how many logs the topic will be sharded into. ``` If these values are not set then topics will be created with 1 partition and 1 replica. -There is also a possibility to set a customized prefix for kafka topics, specifying the environment in which pusub is deployed - +****In case a single Kafka installation is shared between multiple environments, make sure to set a customized prefix for kafka topics, specifying the environment in which pubsub is deployed**** +This variable is used as a prefix to avoid any confusion with Kafka topics and consumer groups and is ****REQUIRED**** to prevent the situation when events are exchanged between pubsub instances belonging to different environments. ``` { "name": "ENV", "value": "folio-testing" } ``` -In case this variable is not set, default "folio" prefix will be used in topic names. +If this variable is not set, default "folio" prefix will be used in topic names, which is acceptable only if a separate Kafka installation is used on the environment. ## Verifying the module can connect and work with kafka