Question

We have a specific format for our config files, where instead of having multiple files – ie, dev.properties, uat.properties, prod.properties – we instead have all the values in one file, but separated by prefixes for each environment. For example:

SERVICE_PORT=9800

DEV_SERVICE_PORT=7800

UAT_SERVICE_PORT=6600

We have an existing class (subclass of PropertyPlaceholderConfigurer) that looks up these values, and decides what prefix to add inside resolvePlaceHolder() based on the IP address where it is executing, ie for a certain IP range, use DEV_ prefix, for another, use UAT_ prefix. These values then get passed on to other beans, in some cases using the context xml, and in some using the @Value${} annotation on some bean constructors. The use of the prefixes is transparent, so all other configs will use SERVICE_PORT (in the example)

We want to change this so that instead of using IPs, we will just detect the active Spring Profile. We have a custom ApplicationContextIniitalizer in our web.xml that detects a java System property that indicates our type of environment.

The problem I have is that at the time resolvePlaceHolder() gets called, there doesn’t seem to be any Active Profiles yet! What I”m doing to detect the active profile is:

1. create an instance of StandardEnvironment
2. call getActiveProfiles()

(2) always seems to return an empty array. This implies that propertyplaceholder resolution occurs before any Spring profiles are activated. Is this correct??

When does the active profile get set, in relation to other events during Spring context loading, like creating the beans, loading property files, etc?

Is it possible to detect the active profile at the time that resolvePlaceHolder() is called? Should I be extending another class instead?

Answer 1

Beans managed within an ApplicationContext may register to be
EnvironmentAware or @Inject the Environment in order to query profile
state or resolve properties directly.

[Source: Environment javadocs ]

Don’t create an instance of StandardEnvironment, inject it into your bean!