030.External Properties - dkkahm/study-springfamework5 GitHub Wiki

External Properties

• Properties file (resources/datasource.properties)

guru.username=John
guru.password=somepass
guru.dburl=adkljdljgdkf

• POJO for properties (FakeDataSource)

public class FakeDataSource {
    private String user;
    private String password;
    private String url;
    ....

Properties Loader

• Since Spring 2.x

@Configuration
@PropertySource("classpath:datasource.properties")
public class PropertyConfig {

    @Value("${guru.username}")
    String user;

    @Value("${guru.password}")
    String password;

    @Value("${guru.dburl}")
    String url;

    @Bean
    public FakeDataSource fakeDataSource() {
        FakeDataSource fakeDataSource = new FakeDataSource();
        fakeDataSource.setUser(user);
        fakeDataSource.setPassword(password);
        fakeDataSource.setUrl(url);;
        return fakeDataSource;
    }

    @Bean
    public static PropertySourcesPlaceholderConfigurer properties() {
        PropertySourcesPlaceholderConfigurer propertySourcesPlaceholderConfigurer = new PropertySourcesPlaceholderConfigurer();
        return propertySourcesPlaceholderConfigurer;
    }
}

• @PropertySource with file

@PropertySource("file:/etc/properties/common/common.properties")

With Environment

• Since 3.x

@Configuration
@PropertySource("classpath:datasource.properties")
public class DataSourceConfiguration {
    @Autowired
    Environment env;

    @Bean
    public FakeDataSource fakeDataSource() {
        FakeDataSource dataSource = new FakeDataSource();
        dataSource.setUser(env.getProperty("guru.username"));
        dataSource.setPassword(env.getProperty("guru.password"));
        dataSource.setUrl(env.getProperty("guru.dburl"));

        return dataSource;
    }
}

• properties can be overriden with environment variables

Configuration with multiple property files

• PropertySource

@PropertySource({"classpath:datasource.properties", "classpath:jms.properties"})

• PropertySources

@PropertySources({
    @PropertySource("classpath:datasource.properties"),
    @PropertySource("classpath:jms.properties")
})

Properties with Profile

• application-{profile}.properties
• with active profile, application-{profile}.properties override application.properties

YML with multiple profile

• application.yml

spring:
    profiles:
        active: de
---
spring:
    profiles: de
guru:
    jms:
        username: JMS Username $$$$ German
---
spring:
    profiles: es
guru:
    jms:
        username: JMS Username $$$$ Spanish

Properties in YML

• define YamlPropertySourceFactory

public class YamlPropertySourceFactory implements PropertySourceFactory {

    @Override
    public PropertySource<?> createPropertySource(String name, EncodedResource encodedResource)
            throws IOException {
        YamlPropertiesFactoryBean factory = new YamlPropertiesFactoryBean();
        factory.setResources(encodedResource.getResource());

        Properties properties = factory.getObject();

        return new PropertiesPropertySource(encodedResource.getResource().getFilename(), properties);
    }
}

• annotate configuration to use yml

@Configuration
@ConfigurationProperties(prefix = "yaml")
@PropertySource(value = "classpath:datasource.yml", factory = YamlPropertySourceFactory.class)
public class DataSourceConfiguration {