PropertyPlaceholderConfigurer for reading from AWS Parameter Store

SSMEncryptedPropertyPlaceholderConfigurer.java

import com.amazonaws.auth.AWSCredentialsProvider;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.config.PropertyPlaceholderConfigurer;

import java.util.Map;
import java.util.Properties;

/**
 * Class for reading properties from AWS Parameter Store and allowing spring to inject them in the
 * environment. Requires two environment variables or to provide the variables in constructor:
 * env -- which is used as the path in parameters store - e.g. - ci
 * env.region -- which region the paramters are in (due to bug we have seen where region not taken from profile
 */
public class SSMEncryptedPropertyPlaceholderConfigurer extends PropertyPlaceholderConfigurer {

    private String environment;

    private String environmentRegion;

    public SSMEncryptedPropertyPlaceholderConfigurer(String environment, String region) {
       this.environment = environment;
       this.environmentRegion = region;
    }

    public SSMEncryptedPropertyPlaceholderConfigurer() {
        environment = System.getProperty("env");
        environmentRegion = System.getProperty("env.region");
    }

    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
        if (environment == null || environmentRegion == null) {
            throw new RuntimeException("no env or region property provided");
        }
        AWSCredentialsProvider awsCredentialsProvider = beanFactory.getBean(AWSCredentialsProvider.class);
        //at the point this function is created, the beans have been created but we have no Autowiring and
        //also propeties have not been injected (obviously since we are doing that). So, here we manually
        ///create SSM Client and inject dependencies manually and call the PostConstruct function as well
        SSMClient ssmClient = new SSMClient(awsCredentialsProvider, environmentRegion);
        ssmClient.init();
        Map<String, String> parametersByPrefix = ssmClient.getParametersByPath("/" + environment, true);
        Properties props = new Properties();
        props.putAll(parametersByPrefix);
        setProperties(props);
        super.postProcessBeanFactory(beanFactory);
    }
}