spring reactor and boot dependency - spring

Is boot a prerequisite to run spring reactor?
I am trying to use spring reactor in a regular web application environment. I can see that the reactor configuration is created. Consumers are registered. Notifications are called. Events are NOT fired. What and how to check?
Configuration
#Configuration
#EnableReactor
public class ReactorConfiguration {
#Bean
Environment env() {
return new Environment();
}
#Bean
Reactor createReactor(Environment env) {
return Reactors.reactor().env(env).dispatcher(Environment.THREAD_POOL)
.get();
}
}
Registering consumers:
#PostConstruct
public void onStartUp() {
logger.debug("Registering Consumers");
reactor.on(Selectors.T(Envelope.class), processParentRequest());
reactor.on(Selectors.T(Bundle.class), processOptimizerRequest());
reactor.on(Selectors.$(Constants.LOWER_ASG), processLowerAsgsRequest());
reactor.on(Selectors.$(constants.SET_CONSUMPTION_LEVEL),
processConsumersRequest());
reactor.on(Selectors.$(constants.SET_GENERATION_LEVEL),
processProducersRequest());
reactor.on(Selectors.$(constants.SET_STORAGE_SUPPLY_LEVEL),
processStoragesRequest());
}
private Consumer<Event<Envelope>> processParentRequest() {
return envelope -> optimizerUpdatingService
.processParentRequest(envelope);
}
private Consumer<Event<Bundle>> processOptimizerRequest() {
return bundle -> eventProcessingDispenser
.processOptimizerRequest(bundle);
}
private Consumer<Event<Envelope>> processLowerAsgsRequest() {
return envelope -> lowerAsgsProcessingService
.processLowerAsgRequest(envelope);
}
private Consumer<Event<Message>> processConsumersRequest() {
return message -> consumersProcessingService
.processConsumersRequest(message);
}
private Consumer<Event<Message>> processProducersRequest() {
return message -> producersProcessingService
.processProducersRequest(message);
}
private Consumer<Event<Message>> processStoragesRequest() {
return message -> storageProcessingService
.processStoragesRequest(message);
}

Spring Boot is not a pre-requisite at all, it simply provides some conveniences when using Spring with Reactor.
There could be any number of things happening. Without any details it's hard to give specific suggestions.

Simple answer is NO.
Spring boot is not a pre requisite but it makes your bootstrapping easy.
All you need is project reactor in your classpath to use reactor

Related

Is it possible to get PathPattern as a Bean in the SpringBoot web and reuse it in user code?

Is it possible to get PathPattern in the SpringBoot web as a Bean and reuse it in user code?
For example, if the url is : /user/1990/lily, it return the url patten on the Controller: /user/{year}/{name}.
This said:
Patterns are parsed on startup and re-used at runtime for efficient
URL matching
Reactor-netty metrics need a uriTagValue to avoid cardinality explosion,
public class Application {
public static void main(String[] args) {
Metrics.globalRegistry
.config()
.meterFilter(MeterFilter.maximumAllowableTags("reactor.netty.http.server", "URI", 100, MeterFilter.deny()));
DisposableServer server =
HttpServer.create()
.metrics(true, s -> { // HERE is the uriTagValue, it's a smaple of how to handle url mapping.
if (s.startsWith("/stream/")) {
return "/stream/{n}";
}
else if (s.startsWith("/bytes/")) {
return "/bytes/{n}";
}
return s;
})
.route(r ->
r.get("/stream/{n}",
(req, res) -> res.sendString(Mono.just(req.param("n"))))
.get("/bytes/{n}",
(req, res) -> res.sendString(Mono.just(req.param("n")))))
.bindNow();
server.onDispose()
.block();
}
}
Config the Netty to enable metrics in a SpringBoot WebFlux app:
#Configuration
public class NettyWebServerConfig {
#Bean
public ReactiveWebServerFactory reactiveWebServerFactory() {
NettyReactiveWebServerFactory factory = new NettyReactiveWebServerFactory();
factory.addServerCustomizers(httpServer -> httpServer
.wiretap(true)
.metrics(true, s -> "") // enable metrics, ignore all uri, if SpringBoot Web expose URI-Match-Patterns as Bean, we can use it here.
);
return factory;
}
}
My wondering is that is it possible to get PathPattern as a Bean in the SpringBoot web and reuse it in reactor-netty metrics code? As simmple as: bestPattern.matchAndExtract(lookupPath)
I tested PathContainer.parsePath(s);, it seems doesn't work.
With this setup, you are not using Spring WebFlux but actually Reactor Netty directly. PathContainer and PathPattern are then irrevelant here.
I don't think reactor-netty is storing anywhere the matching UriPathTemplate when considering the HttpPredicate.

Springdoc GroupedOpenApi not following global parameters set with OperationCustomizer

When using GroupedOpenApi to define an API group, the common set of parameters that are added to every endpoint is not present in the parameters list.
Below are the respective codes
#Bean
public GroupedOpenApi v1Apis() {
return GroupedOpenApi.builder().group("v1 APIs")
// hide all v2 APIs
.pathsToExclude("/api/v2/**", "/v2/**")
// show all v1 APIs
.pathsToMatch("/api/v1/**", "/v1/**")
.build();
}
And the class to add the Standard Headers to all the endpoints
#Component
public class GlobalHeaderAdder implements OperationCustomizer {
#Override
public Operation customize(Operation operation, HandlerMethod handlerMethod) {
operation.addParametersItem(new Parameter().$ref("#/components/parameters/ClientID"));
operation.addSecurityItem(new SecurityRequirement().addList("Authorization"));
List<Parameter> parameterList = operation.getParameters();
if (parameterList!=null && !parameterList.isEmpty()) {
Collections.rotate(parameterList, 1);
}
return operation;
}
}
Actual Output
Expected Output
Workaround
Adding the paths to be included/excluded in the application properties file solves the error. But something at the code level will be much appreciated.
Attach the required OperationCustomizerobject while building the Api Group.
#Bean
public GroupedOpenApi v1Apis(GlobalHeaderAdder globalHeaderAdder) {
return GroupedOpenApi.builder().group("v1 APIs")
// hide all v2 APIs
.pathsToExclude("/api/v2/**", "/v2/**")
// show all v1 APIs
.pathsToMatch("/api/v1/**", "/v1/**")
.addOperationCustomizer(globalHeaderAdded)
.build();
}
Edit: Answer updated with reference to #Value not providing values from application properties Spring Boot
Alternative to add and load OperationCustomizer in the case you declare yours open api groups by properties springdoc.group-configs[0].group= instead definition by Java code in a Spring Configuration GroupedOpenApi.builder().
#Bean
public Map<String, GroupedOpenApi> configureGroupedsOpenApi(Map<String, GroupedOpenApi> groupedsOpenApi, OperationCustomizer operationCustomizer) {
groupedsOpenApi.forEach((id, groupedOpenApi) -> groupedOpenApi.getOperationCustomizers()
.add(operationCustomizer));
return groupedsOpenApi;
}

Spring Boot auto-configured metrics not arriving to Librato

I am using Spring Boot with auto-configure enabled (#EnableAutoConfiguration) and trying to send my Spring MVC metrics to Librato. Right now only my own created metrics are arriving to Librato but auto-configured metrics (CPU, file descriptors, etc) are not sent to my reporter.
If I access a metric endpoint I can see the info generated there, for instance http://localhost:8081/actuator/metrics/system.cpu.count
I based my code on this post for ConsoleReporter. so I have this:
public static MeterRegistry libratoRegistry() {
MetricRegistry dropwizardRegistry = new MetricRegistry();
String libratoApiAccount = "xx";
String libratoApiKey = "yy";
String libratoPrefix = "zz";
LibratoReporter reporter = Librato
.reporter(dropwizardRegistry, libratoApiAccount, libratoApiKey)
.setPrefix(libratoPrefix)
.build();
reporter.start(60, TimeUnit.SECONDS);
DropwizardConfig dropwizardConfig = new DropwizardConfig() {
#Override
public String prefix() {
return "myprefix";
}
#Override
public String get(String key) {
return null;
}
};
return new DropwizardMeterRegistry(dropwizardConfig, dropwizardRegistry, HierarchicalNameMapper.DEFAULT, Clock.SYSTEM) {
#Override
protected Double nullGaugeValue() {
return null;
}
};
}
and at my main function I added Metrics.addRegistry(SpringReporter.libratoRegistry());
For the Librato library I am using in my compile("com.librato.metrics:metrics-librato:5.1.2") build.gradle. Documentation here. I used this library before without any problem.
If I use the ConsoleReporter as in this post the same thing happens, only my own created metrics are printed to the console.
Any thoughts on what am I doing wrong? or what am I missing?
Also, I enabled debug mode to see the "CONDITIONS EVALUATION REPORT" printed in the console but not sure what to look for in there.
Try to make your MeterRegistry for Librato reporter as a Spring #Bean and let me know whether it works.
UPDATED:
I tested with ConsoleReporter you mentioned and confirmed it's working with a sample. Note that the sample is on the branch console-reporter, not the master branch. See the sample for details.

Spring Cloud - HystrixCommand - How to properly enable with shared libraries

Using Springboot 1.5.x, Spring Cloud, and JAX-RS:
I could use a second pair of eyes since it is not clear to me whether the Spring configured, Javanica HystrixCommand works for all use cases or whether I may have an error in my code. Below is an approximation of what I'm doing, the code below will not actually compile.
From below WebService lives in a library with separate package path to the main application(s). Meanwhile MyWebService lives in the application that is in the same context path as the Springboot application. Also MyWebService is functional, no issues there. This just has to do with the visibility of HystrixCommand annotation in regards to Springboot based configuration.
At runtime, what I notice is that when a code like the one below runs, I do see "commandKey=A" in my response. This one I did not quite expect since it's still running while the data is obtained. And since we log the HystrixRequestLog, I also see this command key in my logs.
But all the other Command keys are not visible at all, regardless of where I place them in the file. If I remove CommandKey-A then no commands are visible whatsoever.
Thoughts?
// Example WebService that we use as a shared component for performing a backend call that is the same across different resources
#RequiredArgsConstructor
#Accessors(fluent = true)
#Setter
public abstract class WebService {
private final #Nonnull Supplier<X> backendFactory;
#Setter(AccessLevel.PACKAGE)
private #Nonnull Supplier<BackendComponent> backendComponentSupplier = () -> new BackendComponent();
#GET
#Produces("application/json")
#HystrixCommand(commandKey="A")
public Response mainCall() {
Object obj = new Object();
try {
otherCommandMethod();
} catch (Exception commandException) {
// do nothing (for this example)
}
// get the hystrix request information so that we can determine what was executed
Optional<Collection<HystrixInvokableInfo<?>>> executedCommands = hystrixExecutedCommands();
// set the hystrix data, viewable in the response
obj.setData("hystrix", executedCommands.orElse(Collections.emptyList()));
if(hasError(obj)) {
return Response.serverError()
.entity(obj)
.build();
}
return Response.ok()
.entity(healthObject)
.build();
}
#HystrixCommand(commandKey="B")
private void otherCommandMethod() {
backendComponentSupplier
.get()
.observe()
.toBlocking()
.subscribe();
}
Optional<Collection<HystrixInvokableInfo<?>>> hystrixExecutedCommands() {
Optional<HystrixRequestLog> hystrixRequest = Optional
.ofNullable(HystrixRequestLog.getCurrentRequest());
// get the hystrix executed commands
Optional<Collection<HystrixInvokableInfo<?>>> executedCommands = Optional.empty();
if (hystrixRequest.isPresent()) {
executedCommands = Optional.of(hystrixRequest.get()
.getAllExecutedCommands());
}
return executedCommands;
}
#Setter
#RequiredArgsConstructor
public class BackendComponent implements ObservableCommand<Void> {
#Override
#HystrixCommand(commandKey="Y")
public Observable<Void> observe() {
// make some backend call
return backendFactory.get()
.observe();
}
}
}
// then later this component gets configured in the specific applications with sample configuraiton that looks like this:
#SuppressWarnings({ "unchecked", "rawtypes" })
#Path("resource/somepath")
#Component
public class MyWebService extends WebService {
#Inject
public MyWebService(Supplier<X> backendSupplier) {
super((Supplier)backendSupplier);
}
}
There is an issue with mainCall() calling otherCommandMethod(). Methods with #HystrixCommand can not be called from within the same class.
As discussed in the answers to this question this is a limitation of Spring's AOP.

Spring Boot Actuator: have a customized status as plain text?

I'm trying to integrate Spring Boot Actuator with my companies existing infrastructure. To do this I need to be able to customize the status message. For instance if the app is up and running correctly I need to return a 200 and a plain text body of "HAPPY" from the health actuator endpoint.
Is such customization currently possible? Since the Status class is final I can't extend it, but I think that would work.
Spring Boot uses a HealthAggregator to aggregate all of the statuses from the individual health indicators into a single health for the entire application. You can plug in a custom aggregator that delegates to Boot's default aggregator, OrderedHealthAggregator, and then maps UP to HAPPY:
#Bean
public HealthAggregator healthAggregator() {
return new HappyHealthAggregator(new OrderedHealthAggregator());
}
static class HappyHealthAggregator implements HealthAggregator {
private final HealthAggregator delegate;
HappyHealthAggregator(HealthAggregator delegate) {
this.delegate = delegate;
}
#Override
public Health aggregate(Map<String, Health> healths) {
Health result = this.delegate.aggregate(healths);
if (result.getStatus() == Status.UP) {
return new Health.Builder(new Status("HAPPY"), result.getDetails())
.build();
}
return result;
}
}
If you want to take complete control over the format of the response, then you'll need to write your own MVC endpoint implementation. You could use the existing HealthMvcEndpointclass in Spring Boot as a super class and override its invoke method.

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