How to get my configuration values ​​in yml - using dropwizard (microservice) Jersey DI @Injection?

Question

here are my code snippets.

here is my yml file:

productionServer: host: production-server.amazonaws.com publicIp: xx.xx.xx.xx privateIp: xx.xx.xx.xx userName: xx.xx.xx.xx password: xx.xx.xx.xx remoteFilePath: fake/path/ fileName: test.txt privateKey: private-public-key.ppk server: applicationConnectors: - type: http port: 8080 - type: https port: 8443 keyStorePath: key.keystore keyStorePassword: password validateCerts: false adminConnectors: - type: http port: 8081 - type: https port: 8444 keyStorePath: key.keystore keyStorePassword: password validateCerts: false 

MyConfiguration Class:

 import io.dropwizard.Configuration; public class MyConfiguration extends Configuration{ @NotNull @JsonProperty private ProductionServer productionServer; // getters public class ProdctionServer{ @NotEmpty @JsonProperty private host; @NotEmpty @JsonProperty private publicIp; // getters 

Application Class:

 import io.dropwizard.Application; public class MyApplication extends Application<MyConfiguration> { public static void main(String[] args) throws Exception{ new MysApplication().run(args); } @Override public String getName(){ return "micro-service"; } @Override public void initialize(Bootstrap<MyConfiguration> bootstrap){} @Override public void run(MyConfiguration conf, Environment environment ){ final MyResource myResource = new MyResource(); // health check // environment.healthChecks().register("template",healthCheck); System.out.println( "==> " + conf ); System.out.println( "==> " + conf.getProductionServer() ); // register environment.jersey().register( MyResource ); 

and when running this application:

i received registration as follows:

 ==> MyConfiguration{server=DefaultServerFactory{applicationConnectors=[ io.dropwizard.jetty.HttpConnectorFactory@623e088f , io.dropwizard.jetty.HttpsConnectorFactory@39fcbef6 ], adminConnectors=[ io.dropwizard.jetty.HttpConnectorFactory@34f22f9d , io.dropwizard.jetty.HttpsConnectorFactory@77d67cf3 ], adminMaxThreads=64, adminMinThreads=1, applicationContextPath=/, adminContextPath=/}, logging=DefaultLoggingFactory{level=INFO, loggers={}, appenders=[ io.dropwizard.logging.ConsoleAppenderFactory@663411de ]}} ==> com.mycompany.myproject.model.ProductionServer@5b04476e 

means it successfully gets my yaml value. but my problem is introducing a DI or dependency on the MyConfiguration class. I cannot get the value of my ProductionServer, although the MyConfiguration object seems to be invalid in my service.

here is my code snippet linking MyService.class and MyConfiguration.class

DependencyBinder.class

import org.glassfish.hk2.utilities.binding.AbstractBinder;

public class DependencyBinder extends AbstractBinder {

 @Override protected void configure() { bind(MyConfiguration.class).to(MyConfiguration.class); bind(MyService.class).to(MyService.class); } 

MyService.class

 public class MyService { @Inject MyConfiguration conf; public void invoke(){ System.out.println( "=============================== " ); System.out.println( "==> " + conf ); System.out.println("==> " + conf.getProductionServer() ); } 

and during invoke () method call ... I got the log as follows:

 =============================== ==> MyConfiguration{server=DefaultServerFactory{applicationConnectors=[ io.dropwizard.jetty.HttpConnectorFactory@34e82c4d ], adminConnectors=[ io.dropwizard.jetty.HttpConnectorFactory@19b70fbd ], adminMaxThreads=64, adminMinThreads=1, applicationContextPath=/, adminContextPath=/}, logging=DefaultLoggingFactory{level=INFO, loggers={}, appenders=[ io.dropwizard.logging.ConsoleAppenderFactory@543f81c9 ]}} ==> null 

now my problem is introducing the DI or dependencies of the MyConfiguration class in MyService.class. I cannot get the value of my ProductionServer, although the MyConfiguration object seems to be invalid in my service. please give me some permission? Thnx.

Answer 1

The problem is that with this configuration

 bind(MyConfiguration.class).to(MyConfiguration.class); 

HK2 will create a new instance of MyConfiguration . It will not be the same instance populated by DW. However, you can use the instance created by DW just by binding the same instance in your HK2 configuration

 public class MyApplication extends Application<MyConfiguration> { @Override public void run(final MyConfiguration config, Environment env) { env.jersey().register(new AbstractBinder() { @Override protected void configure() { bind(config).to(MyConfiguration.class); } }); } }