I was trying to correctly identify application using Oracle JDBC Thin driver to the database server in Spring Boot 2.2. In Spring Boot 1.5 this was accomplished by setting the v$session.program connection property as I explained here. The setup was:
spring:
datasource:
hikari:
data-source-properties:
v$session.program: AppName
Unfortunately above no longer works in Spring Boot 2.2. Now surprisingly the property name will be resolved as spring.datasource.hikari.data-source-properties.vsession.program with the dollar sign silently removed.
Others have already reported this strange behaviour in Problem with yml configuration file parsing map #13404 issue. Spring Boot binder has become stricter as explained in this comment and going forward property name with special characters has to escaped with both quotes and square brackets:
spring:
datasource:
hikari:
data-source-properties:
"[v$session.program]": AppName
This new escape syntax applies to property names in both .yml and .properties resources.