How to use

Configuration

in

com.hotels.styx.api.configuration

/**
 * Returns the value to which the specified key is mapped, converted to String
 * or {@code Optional.absent} if this configuration source contains no mapping for the key.
 *
 * @param key the key whose associated value is to be returned
 * @return the value to which the specified key is mapped, or
 * {@code Optional.absent} if this map contains no mapping for the key
 */
default Optional<String> get(String key) {
  return get(key, String.class);
}

@Override
public <X> X as(Class<X> type) {
  return configuration.as(type);
}

private Optional<PluginsMetadata> readPluginsConfig() {
  return configuration.get("plugins", PluginsMetadata.class);
}

  @Override
  public StyxService create(Environment environment, Configuration serviceConfiguration) {
    GraphiteConfig graphiteConfig = serviceConfiguration.as(GraphiteConfig.class);

    String host = graphiteConfig.host();
    int port = graphiteConfig.port();

    return new GraphiteReporterService.Builder()
        .serviceName(format("Graphite-Reporter-%s:%d", host, port))
        .prefix(graphiteConfig.prefix())
        .graphiteSender(new NonSanitizingGraphiteSender(host, port))
        .reportingInterval(graphiteConfig.intervalMillis(), MILLISECONDS)
        .metricRegistry(codaHaleMetricRegistry(environment))
        .build();
  }
}

/**
 * Returns the value to which the specified key is mapped, converted to String
 * or {@code Optional.absent} if this configuration source contains no mapping for the key.
 *
 * @param key the key whose associated value is to be returned
 * @return the value to which the specified key is mapped, or
 * {@code Optional.absent} if this map contains no mapping for the key
 */
default Optional<String> get(String key) {
  return get(key, String.class);
}

@Override
public <T> Optional<T> get(String key, Class<T> tClass) {
  return configuration.get(key, tClass);
}

@Override
public LoadBalancerFactory get() {
  return configurations.get(LOAD_BALANCING_STRATEGY_KEY)
      .map(this::newFactoryInstance)
      .orElseGet(this::busyConnectionBalancer);
}

@Override
public <X> Optional<X> get(String key, Class<X> type) {
  Optional<X> found = Optional.ofNullable(config.get(key)).map(type::cast);
  if (!found.isPresent()) {
    return parent.get(key, type);
  }
  return found;
}

@Override
public <X> Optional<X> get(String key, Class<X> type) {
  Optional<X> found = Optional.ofNullable(config.get(key)).map(type::cast);
  if (!found.isPresent()) {
    return parent.get(key, type);
  }
  return found;
}

  @Override
  public RetryPolicy create(Environment environment, Configuration retryPolicyConfiguration) {
    int retriesCount = retryPolicyConfiguration.get("count", Integer.class)
        .orElse(1);
    return new RetryNTimes(retriesCount);
  }
}

@Override
public Registry<BackendService> create(Environment environment, Configuration registryConfiguration) {
  String originsFile = registryConfiguration.get("originsFile", String.class)
      .map(Factory::requireNonEmpty)
      .orElseThrow(() -> new ConfigurationException(
          "missing [services.registry.factory.config.originsFile] config value for factory class FileBackedBackendServicesRegistry.Factory"));
  FileMonitorSettings monitorSettings = registryConfiguration.get("monitor", FileMonitorSettings.class)
      .orElseGet(FileMonitorSettings::new);
  return registry(originsFile, monitorSettings);
}

  private String factoryClassName(String strategyName) {
    String key = format("loadBalancing.strategies.%s.factory.class", strategyName);

    return configurations.get(key).orElseThrow(() -> new MissingConfigurationException(key));
  }
}

  @Override
  public RetryPolicy create(Environment environment, Configuration retryPolicyConfiguration) {
    int retriesCount = retryPolicyConfiguration.get("count", Integer.class)
        .orElse(1);
    return new RetryNTimes(retriesCount);
  }
}

/**
 * Creates the services whose configuration has the specified key.
 *
 * @param <T>           service type
 * @param configuration Styx configuration
 * @param key           Factory configuration attribute
 * @param serviceClass  Service class
 * @return services, if such a configuration key exists
 */
public static <T> Map<String, T> loadServices(Configuration configuration, Environment environment, String key, Class<? extends T> serviceClass) {
  return configuration.get(key, JsonNode.class)
      .<Map<String, T>>map(node -> servicesMap(node, environment, serviceClass))
      .orElse(emptyMap());
}

  @Override
  public Registry<BackendService> create(Environment environment, Configuration registryConfiguration) {
    BackendService service = registryConfiguration.get("backendService", BackendService.class)
        .orElseThrow(() -> new ConfigurationException(
            "missing [services.registry.factory.config.backendService] config value for factory class TestBackendProvider.Factory"));
    return new TestBackendProvider(service);
  }
}

  @Override
  public StyxService create(Environment environment, Configuration serviceConfiguration) {
    String domain = serviceConfiguration.get("domain").orElse("com.hotels.styx");

    return new JmxReporterService(domain, codaHaleMetricRegistry(environment));
  }
}

  @Test
  public void doesNotContainConfigurationsValue() {
    assertThat(emptyConfiguration.get("any value"), is(isAbsent()));
    assertThat(emptyConfiguration.get("xsfsd", Integer.class), is(isAbsent()));
  }
}

/**
 * Create factory configured with a particular key, then uses the factory's create method
 * to create its product.
 *
 * @param <E>           service type
 * @param configuration Styx configuration
 * @param key           Factory configuration attribute
 * @param serviceClass  Service class
 * @return service, if such a configuration key exists
 */
public static <E extends RetryPolicy> Optional<E> loadRetryPolicy(
    Configuration configuration,
    Environment environment,
    String key,
    Class<? extends E> serviceClass) {
  return configuration
      .get(key, ServiceFactoryConfig.class)
      .map(factoryConfig -> {
        RetryPolicyFactory factory = newInstance(factoryConfig.factory(), RetryPolicyFactory.class);
        JsonNodeConfig config = factoryConfig.config();
        return serviceClass.cast(factory.create(environment, config));
      });
}

/**
 * Create a {@link com.hotels.styx.client.StyxBackendServiceClient} related factory configured with a particular key,
 * then uses the factory's create method to create its product.
 *
 * @param <E>           service type
 * @param configuration Styx configuration
 * @param key           Factory configuration attribute
 * @param serviceClass  Service class
 * @param activeOrigins source of active connections for purpose of load balancing
 * @return service, if such a configuration key exists
 */
public static <E extends LoadBalancer> Optional<E> loadLoadBalancer(
    Configuration configuration,
    Environment environment,
    String key,
    Class<? extends E> serviceClass,
    ActiveOrigins activeOrigins) {
  return configuration
      .get(key, ServiceFactoryConfig.class)
      .map(factoryConfig -> {
        try {
          LoadBalancerFactory factory = newInstance(factoryConfig.factory(), LoadBalancerFactory.class);
          return serviceClass.cast(factory.create(environment, factoryConfig.config(), activeOrigins));
        } catch (Exception e) {
          throw new ConfigurationException("Error creating service", e);
        }
      });
}

@Override
public Eventual<LiveHttpResponse> intercept(LiveHttpRequest request, Chain chain) {
  String header = xHcomPluginsHeader(request);
  final String configPath = environment.pluginConfig(String.class);
  String pluginsList = environment.configuration().get("plugins.active").get();
  LiveHttpRequest newRequest = request.newBuilder()
      .header(X_HCOM_PLUGINS_HEADER, header)
      .header(X_HCOM_PLUGINS_CONFIGURATION_PATH, configPath)
      .header(X_HCOM_PLUGINS_LIST, pluginsList)
      .header("X-Hcom-Styx-Started", styxStarted)
      .header("X-Hcom-Styx-Stopped", styxStopped)
      .build();
  Function<ByteBuf, String> byteBufStringFunction = byteBuf -> byteBuf.toString(Charsets.UTF_8);
  return chain.proceed(newRequest)
      .flatMap(response -> response.aggregate(1 * 1024 * 1024))
      .map(response ->
          response.newBuilder()
              .header(X_HCOM_PLUGINS_HEADER, header)
              .header(X_HCOM_PLUGINS_CONFIGURATION_PATH, configPath)
              .header(X_HCOM_PLUGINS_LIST, pluginsList)
              .header("X-Hcom-Styx-Started", styxStarted)
              .header("X-Hcom-Styx-Stopped", styxStopped)
              .build())
      .map(HttpResponse::stream);
}