I'm trying to use Spring cloud bus with Kafka in my microservices application, and indeed I could use it, but only data which is controlled by Spring cloud config server got refreshed!
I'm using jdbc back-end with my config server, and in order to simulate my need, I'm changing some value in properties file in one of my services, beside the properties table, and call the /monintor end point again (mentioned here section 4.3 https://www.baeldung.com/spring-cloud-bus); as a result, only data coming from properties table is changed.
This is the yml file for my Config server
spring:
cloud:
config:
server:
jdbc:
sql: SELECT KEY,VALUE from PROPERTIES where APPLICATION=? and PROFILE=? and LABEL=?
order: 1
stream:
kafka:
binder:
brokers: localhost:9092
datasource:
url: jdbc:mysql://localhost:3306/sweprofile?zeroDateTimeBehavior=convertToNull
username: 123
password: 123ertbnm
hikari:
maximum-pool-size: 10
connection-timeout: 5000
profiles:
active:
- jdbc
application:
name: configServer
These are yml files for One of my Miscroservices and its propeties file respectively
spring:
datasource:
username: 123
password: 123ertbnm
url: jdbc:mysql://localhost:3306/sweprofile?zeroDateTimeBehavior=convertToNull
jpa:
properties:
hibernate:
format_sql: true
ddl-auto: none
application:
name: auth-service
cloud:
config:
discovery:
enabled: true
service-id: configServer
bus:
refresh:
enabled: true
profiles:
active: jdbc
management:
endpoints:
web:
exposure:
include: ["health","info","refresh", "bus-refresh"]
# This line is dummy data for testing purpose
ali.man = " Ola 12333"
This is snapshot from rest controller
@RestController
@RequestMapping("/user")
@RefreshScope
public class AuthController {
private UserAuthService userAuthService;
@Value("${name}")
private String name; // changed normally
// Calling the key value mentioned in properties file after changing
@Value("${ali.man}")
private String k; // -> not changed
public AuthController(UserAuthService userAuthService) {
this.userAuthService = userAuthService;
}
@GetMapping("authTest")
public String getAuth() {
return name + k;
}
}
What did I miss? Why value from Properties file is not changed? hopefully I can use Spring cloud bus with Kafka to refresh these external data.
After some hours of investigation, I found that there is some recommended way. Cloud bus can send Refresh Event and Spring boot has RefreshEvent Listener to that event; this what I build my solution on.
So when event is sent by the bus; all instances will do the same logic ( Refreshing data ) on the loaded in memory configurations.
I used this snippet to apply this
@Configuration
public class ReloadLookupEvent implements ApplicationListener<RefreshScopeRefreshedEvent> {
@Autowired
private CacheService cacheService;
@Override
public void onApplicationEvent(RefreshScopeRefreshedEvent event) {
cacheService.refreshLookUp();
}
}
I could refresh all other configurations on demand, maybe it is a workaround, but acceptable.