How Spring Cloud Config Server PUSH plain text files to Config Client Application?

问题

What I have implemented so far are:

Spring Cloud Config Server with "native" repo.

spring.profiles.active: native

spring.cloud.config.server.native.searchLocations: file:/path/to/config-repo

Config Server is pushing notification to Config Client App through RabbitMQ, as http://cloud.spring.io/spring-cloud-config/spring-cloud-config.html#_push_notifications_and_spring_cloud_bus
Config Client App has @RefreshScope annotated on Service bean.

So /config-repo has 3 files - application.yaml, client.yaml and client.json All yaml properties changes will be auto reloaded by Config Client App for sure. However, client.json didn't.

Based on https://github.com/spring-cloud/spring-cloud-config/issues/147, I can fetch the file on Config Client App through REST api call to Config Server, with /{appname}/{profile}/{label}/client.json

Question are:

1) Is Config Server monitoring this plain text file changes by "native"?

2) how can Config Client App auto reload this client.json once it's updated? (I can have schedule task to call Config server, but this isn't ideal.)

回答1:

i am sloving like this way (not finnished yet): i have spring.cloud.config.server.native.serach-locations in form of comma separated list of URIs

file:/c:/repo/a,file:/c:/repo/b

I created FileMonitorConfiguration bean (but it have some problem, because it is scheduled 2 times, a bean itself and a spring enhaced instance, I am not fammiliar with this)

And implemented (just draft) NativePropertyPathNotificationExtractor

@Configuration
@EnableAutoConfiguration
@EnableConfigServer
public class ConfigServerApplication {
    public static void main(String[] args) {
        SpringApplication.run(ConfigServerApplication.class, args);
    }

    @Bean
    NativePropertyPathNotificationExtractor nativePropertyPathNotificationExtractor(@Autowired(required = false) NativeEnvironmentRepository nativeRepo) {
        return new NativePropertyPathNotificationExtractor(nativeRepo);
    }

    @Bean
    FileMonitorConfiguration fileMonitorConfiguration() {
        return new FileMonitorConfiguration();
    }
}

@Order(Ordered.LOWEST_PRECEDENCE - 500)
public class NativePropertyPathNotificationExtractor implements PropertyPathNotificationExtractor {
    private final Set<Path> searchPaths;

    public NativePropertyPathNotificationExtractor(NativeEnvironmentRepository nativeRepo) {
        searchPaths = searchLocations(nativeRepo);
    }

    @Override
    public PropertyPathNotification extract(MultiValueMap<String, String> headers, Map<String, Object> payload) {

        // FileMonitor with empty headers, so if some there, ignore
        if (false == headers.isEmpty()) {
            return null;
        }
        if (null == searchPaths) {
            return null;
        }

        Path path = pathFromPayload(payload);
        if (null == path) {
            return null;
        }

        for (Path searchPath : searchPaths) {
            Path relative = searchPath.relativize(path);
            // just a try ;-)
            if (true == relative.startsWith("..")) {
                continue;
            }

            return new PropertyPathNotification(relative.toString());
        }

        return null;
    }

    private Path pathFromPayload(Map<String, Object> payload) {
        if (null == payload) {
            return null;
        }
        if (true == payload.isEmpty()) {
            return null;
        }
        if (false == payload.containsKey("path")) {
            return null;
        }
        if (null == payload.get("path")) {
            return null;
        }
        if (true == StringUtils.isEmpty(payload.get("path").toString())) {
            return null;
        }
        return Paths.get(payload.get("path").toString()).normalize().toAbsolutePath();
    }

    private Set<Path> searchLocations(NativeEnvironmentRepository nativeRepo) {
        if (null == nativeRepo) {
            return null;
        }
        if (null == nativeRepo.getSearchLocations()) {
            return null;
        }

        final Set<Path> paths = new LinkedHashSet<>();
        for (String location : nativeRepo.getSearchLocations()) {
            try {
                paths.add(Paths.get(new URI(location)).normalize().toAbsolutePath());
            } catch (Exception e) {
                System.err.println("Nevalidne search location uri: " + location);
            }
        }
        return paths;

    }
}