Best practice for reading endpoint URLs/variables from a file in WSO2 ESB project?
I'm working on a WSO2 ESB project, and currently, I have endpoint configurations directly written into the XML files. I want to adopt a more maintainable approach by reading endpoint URLs and variables from a separate file.
What is the best practice for achieving this in WSO2 ESB projects? Are there specific design patterns or configurations that I should follow to externalize endpoint configurations and make the project more flexible? Any examples or recommended tools for managing endpoint configurations in a file for a WSO2 ESB project would be greatly appreciated.
There are two ways to achieve this either by having an environment-specific properties file or injecting the URLs via environment variables.
If you are using a properties file you can add your properties to a file named file.properties and place it in the <MI_HOME>/conf directory and it will be picked up automatically. If you have a custom properties file, let's say custom.properties you can pass the file path on server startup like below by adding it to the startup script so it will be loaded.
-Dproperties.file.path=/home/user/ei_configs/dev/custom.properties
Once the file is loaded. You can read the properties as Properties like below and use URL templates to use the values in this property or you can directly use the values as shown below.
Read more here
<property name="someProp" expression="get-property('file','propName')" scope="default" />
OR
<?xml version="1.0" encoding="UTF-8"?>
<endpoint xmlns="http://ws.apache.org/ns/synapse" name="StockQuoteEndPoint">
<address uri="$FILE:stockQuoteEP"/>
</endpoint>
If you inject them as environment variables you can read them as below.
<?xml version="1.0" encoding="UTF-8"?>
<endpoint xmlns="http://ws.apache.org/ns/synapse" name="JSON_EP">
<address uri="$SYSTEM:stockQuoteEP"/>
</endpoint>