Bootstrap Order PropertySource

Question

We have a Spring-Boot application in which we use Eureka to open Spring Cloud Config and get the configurations. We integrate Vault to enter secure / confidential information and have problems loading and resolving settings. The project that we use as the Vault client, vault-spring-boot-starter , and it works fine until we use it together with the configuration server through the eureka.

In particular, the Eureka access URL contains parameters / credentials that are retrieved from Vault. When all components are turned on, the Eureka request fails when DiscoveryClient tries to access a URL where parameters have not yet been filled / replaced.

( Example: http://${user}:${pass}..... )

Trying to specify @Order and

@AutoConfigureBefore({EurekaClientAutoConfiguration.class, DiscoveryClientConfigServiceAutoConfiguration.class})

in the spring-boot-starter repository, VaultBootstrapConfiguration does not seem to be affected. I believe the problem is with the ordering in which PropertySources are processed, but I cannot successfully implement Vault PropertySource before Eureka's. How can we instruct the custom / Vault PropertySourceLocator logic to execute before accessing the DiscoveryClient and configuration server?

Update

We are using the spring-eye version of Angel.SR6.

I added the @Order (Ordered.HIGHEST_PRECEDENCE) note for VaultPropertySourceLocator as recommended, but parameter resolution still doesn't work. With Spring debugging logging turned on, I believe that the Vault PropertySource actually exists, but for some reason it is not used. I changed the code so that VaultConfiguration implements SmartLifecycle and Ordered (with order = 0 and phase = Integer.MIN_VALUE), which can affect things. I will need to do more debugging in order to try to isolate what is happening.

Answer 1

I was able to solve my problem. I tried several different approaches, including Spring AOP and LTW, which did not work like trying to instantiate too early - so that VaultPropertySource was available before Eureka DiscoveryClient made the call.

My working solution has:

For the beans storage instance, earlier than the Eureka bean, and the configuration starts the instance creation:

• @Ordered or implementations of PriorityOrdered in VaultPropertySourceLocator . My VaultPropertySourceLocator also includes a SmartLifecycle implementation, since I saw a non-deterministic result with parts of an Eureka bean instance, which sometimes happens before Vault beans. My order is Ordered.HIGHEST_PRECEDENCE , and the phase is Integer.MIN_VALUE .

To register a VaultPropertySource as a PropertySource, which is used to resolve parameters when posting Eureka beans / configuration:

• Passing in the environment a reference to the VaultPropertySource , which self-registers in the list of the PropertySources environment and exists when Eureka beans instantiates and sets the serviceUrl property during creation and deployment / resolution of EurekaClientConfigBean properties.