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Dynamic configuration refresh

For AppConfig profiles, the starter keeps polling AWS after startup and refreshes the Spring application context when a new configuration version is deployed. This is built on Spring Cloud Context's ContextRefresher. (Secrets Manager imports are read once at startup and are not polled.)

Polling​

Each JeapAppConfigDataClient runs a daemon ThreadPoolTaskScheduler (jeap-aws-appconfig-polling-scheduler-) that re-fetches the latest configuration on an interval. The interval comes from AppConfig's nextPollIntervalInSeconds response, falling back to required-minimum-poll-interval-in-seconds (or 60 seconds if unset). JeapAppConfigDataClientFactory reuses one client per profile-env-app combination so that only a single AppConfig session is open per profile. When AppConfig returns an empty payload the configuration is treated as unchanged and no refresh happens.

Refresh flow​

AppConfigContextRefresher (a bean from JeapAWSAppConfigAutoConfig) registers itself as the JeapAppConfigDataChangedListener on every AppConfigPropertySource backed by a JeapAppConfigDataClient. When a polled profile changes it calls ContextRefresher.refresh().

What gets refreshed​

A refresh re-binds, without restarting the application:

  • the Spring Environment of the application context
  • @ConfigurationProperties beans
  • beans annotated @RefreshScope
  • feature flags based on the jeap-spring-boot-featureflag-starter

Plain singleton beans that captured a value at construction time are not re-injected — use @ConfigurationProperties or @RefreshScope for values that must change at runtime.