EnvironmentMvcEndpoint throws exception for unresolvable properties

[brenuart]

The EnvironmentMvcEndpoint throws an exception for unresolvable properties instead of printing their unresolved value.

Suppose the following application.properties:

my.foo = ${my.bar}

A call to the endpoint /env shows the applicationConfig entry with the properties unresolved:

"applicationConfig: [classpath:/application.properties]": {
   "my.foo": "${my.bar}"
}

However, a call to /env/my.* throws an exception complaining about ${my.bar} being unresolvable.
This behaviour is annoying when the environment contains some properties that are not used in a given setup (think about feature.enabled=false with an incomplete configuration set for the feature feature).

Note: tested with SpringBoot 1.3.8.RELEASE and 1.4.4.RELEASE

[wilkinsona]

See also #8282

[philwebb]

Not sure if it's useful, but RelaxedPropertyResolver.ignoringUnresolvableNestedPlaceholders might help when it comes to fixing this.

[brenuart]

Yes it will - but it will then be applicable to the entire Environment - which may not be desired.
I tried to modify the EnvironmentMvcEndpoint to make use of such property resolver instead of delegating to the Environment for property resolution. But I'm not sure it is the way to go...