policy-agent/src/main/java/org/oransc/policyagent/tasks/ServiceSupervision.java

   1 /*-
   2  * ========================LICENSE_START=================================
   3  * O-RAN-SC
   4  * %%
   5  * Copyright (C) 2019 Nordix Foundation
   6  * %%
   7  * Licensed under the Apache License, Version 2.0 (the "License");
   8  * you may not use this file except in compliance with the License.
   9  * You may obtain a copy of the License at
  10  *
  11  *      http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  * Unless required by applicable law or agreed to in writing, software
  14  * distributed under the License is distributed on an "AS IS" BASIS,
  15  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  * See the License for the specific language governing permissions and
  17  * limitations under the License.
  18  * ========================LICENSE_END===================================
  19  */
  20
  21 package org.oransc.policyagent.tasks;
  22
  23 import java.time.Duration;
  24
  25 import org.oransc.policyagent.clients.A1ClientFactory;
  26 import org.oransc.policyagent.repository.Lock;
  27 import org.oransc.policyagent.repository.Lock.LockType;
  28 import org.oransc.policyagent.repository.Policies;
  29 import org.oransc.policyagent.repository.Policy;
  30 import org.oransc.policyagent.repository.Service;
  31 import org.oransc.policyagent.repository.Services;
  32 import org.slf4j.Logger;
  33 import org.slf4j.LoggerFactory;
  34 import org.springframework.beans.factory.annotation.Autowired;
  35 import org.springframework.scheduling.annotation.EnableScheduling;
  36 import org.springframework.stereotype.Component;
  37
  38 import reactor.core.publisher.Flux;
  39 import reactor.core.publisher.Mono;
  40
  41 /**
  42  * Periodically checks that services with a keepAliveInterval set are alive. If
  43  * a service is deemed not alive, all the service's policies are deleted, both
  44  * in the repository and in the affected Rics, and the service is removed from
  45  * the repository. This means that the service needs to register again after
  46  * this.
  47  */
  48 @Component
  49 @EnableScheduling
  50 @SuppressWarnings("squid:S2629") // Invoke method(s) only conditionally
  51 public class ServiceSupervision {
  52     private static final Logger logger = LoggerFactory.getLogger(ServiceSupervision.class);
  53     static final int CONCURRENCY_RIC = 1; // How may paralell requests that is sent
  54     private final Services services;
  55     private final Policies policies;
  56     private A1ClientFactory a1ClientFactory;
  57     private final Duration checkInterval;
  58
  59     @Autowired
  60     public ServiceSupervision(Services services, Policies policies, A1ClientFactory a1ClientFactory) {
  61         this(services, policies, a1ClientFactory, Duration.ofMinutes(1));
  62     }
  63
  64     public ServiceSupervision(Services services, Policies policies, A1ClientFactory a1ClientFactory,
  65         Duration checkInterval) {
  66         this.services = services;
  67         this.policies = policies;
  68         this.a1ClientFactory = a1ClientFactory;
  69         this.checkInterval = checkInterval;
  70         start();
  71     }
  72
  73     private void start() {
  74         logger.debug("Checking services starting");
  75         createTask().subscribe(null, null, () -> logger.error("Checking services unexpectedly terminated"));
  76     }
  77
  78     private Flux<?> createTask() {
  79         return Flux.interval(this.checkInterval) //
  80             .flatMap(notUsed -> checkAllServices());
  81     }
  82
  83     Flux<Policy> checkAllServices() {
  84         return Flux.fromIterable(services.getAll()) //
  85             .filter(Service::isExpired) //
  86             .doOnNext(service -> logger.info("Service is expired: {}", service.getName())) //
  87             .doOnNext(service -> services.remove(service.getName())) //
  88             .flatMap(this::getAllPoliciesForService) //
  89             .flatMap(this::deletePolicy, CONCURRENCY_RIC);
  90     }
  91
  92     @SuppressWarnings("squid:S2629") // Invoke method(s) only conditionally
  93     private Flux<Policy> deletePolicy(Policy policy) {
  94         Lock lock = policy.ric().getLock();
  95         return lock.lock(LockType.SHARED) //
  96             .doOnNext(notUsed -> policies.remove(policy)) //
  97             .flatMap(notUsed -> deletePolicyInRic(policy))
  98             .doOnNext(notUsed -> logger.debug("Policy deleted due to service inactivity: {}, service: {}", policy.id(),
  99                 policy.ownerServiceName())) //
 100             .doOnNext(notUsed -> lock.unlockBlocking()) //
 101             .doOnError(throwable -> lock.unlockBlocking()) //
 102             .doOnError(throwable -> logger.debug("Failed to delete inactive policy: {}, reason: {}", policy.id(),
 103                 throwable.getMessage())) //
 104             .flatMapMany(notUsed -> Flux.just(policy)) //
 105             .onErrorResume(throwable -> Flux.empty());
 106     }
 107
 108     private Flux<Policy> getAllPoliciesForService(Service service) {
 109         return Flux.fromIterable(policies.getForService(service.getName()));
 110     }
 111
 112     private Mono<Policy> deletePolicyInRic(Policy policy) {
 113         return a1ClientFactory.createA1Client(policy.ric()) //
 114             .flatMap(client -> client.deletePolicy(policy) //
 115                 .onErrorResume(exception -> handleDeleteFromRicFailure(policy, exception)) //
 116                 .map(nothing -> policy));
 117     }
 118
 119     private Mono<String> handleDeleteFromRicFailure(Policy policy, Throwable e) {
 120         logger.warn("Could not delete policy: {} from ric: {}. Cause: {}", policy.id(), policy.ric().name(),
 121             e.getMessage());
 122         return Mono.empty();
 123     }
 124 }