Merge "Remove code smell and bug"
[nonrtric.git] / 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 public class ServiceSupervision {
51     private static final Logger logger = LoggerFactory.getLogger(ServiceSupervision.class);
52     private final Services services;
53     private final Policies policies;
54     private A1ClientFactory a1ClientFactory;
55     private final Duration checkInterval;
56
57     @Autowired
58     public ServiceSupervision(Services services, Policies policies, A1ClientFactory a1ClientFactory) {
59         this(services, policies, a1ClientFactory, Duration.ofMinutes(1));
60     }
61
62     public ServiceSupervision(Services services, Policies policies, A1ClientFactory a1ClientFactory,
63         Duration checkInterval) {
64         this.services = services;
65         this.policies = policies;
66         this.a1ClientFactory = a1ClientFactory;
67         this.checkInterval = checkInterval;
68         start();
69     }
70
71     private void start() {
72         logger.debug("Checking services starting");
73         createTask().subscribe(null, null, () -> logger.error("Checking services unexpectedly terminated"));
74     }
75
76     private Flux<?> createTask() {
77         return Flux.interval(this.checkInterval) //
78             .flatMap(notUsed -> checkAllServices());
79     }
80
81     Flux<Policy> checkAllServices() {
82         return Flux.fromIterable(services.getAll()) //
83             .filter(Service::isExpired) //
84             .doOnNext(service -> logger.info("Service is expired: {}", service.getName())) //
85             .doOnNext(service -> services.remove(service.getName())) //
86             .flatMap(this::getAllPoliciesForService) //
87             .flatMap(this::deletePolicy);
88     }
89
90     @SuppressWarnings("squid:S2629") // Invoke method(s) only conditionally
91     private Flux<Policy> deletePolicy(Policy policy) {
92         Lock lock = policy.ric().getLock();
93         return lock.lock(LockType.SHARED) //
94             .doOnNext(notUsed -> policies.remove(policy)) //
95             .flatMap(notUsed -> deletePolicyInRic(policy))
96             .doOnNext(notUsed -> logger.debug("Policy deleted due to service inactivity: {}, service: {}", policy.id(),
97                 policy.ownerServiceName())) //
98             .doOnNext(notUsed -> lock.unlockBlocking()) //
99             .doOnError(throwable -> lock.unlockBlocking()) //
100             .doOnError(throwable -> logger.debug("Failed to delete inactive policy: {}, reason: {}", policy.id(),
101                 throwable.getMessage())) //
102             .flatMapMany(notUsed -> Flux.just(policy)) //
103             .onErrorResume(throwable -> Flux.empty());
104     }
105
106     private Flux<Policy> getAllPoliciesForService(Service service) {
107         synchronized (policies) {
108             return Flux.fromIterable(policies.getForService(service.getName()));
109         }
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     @SuppressWarnings("squid:S2629") // Invoke method(s) only conditionally
120     private Mono<String> handleDeleteFromRicFailure(Policy policy, Throwable e) {
121         logger.warn("Could not delete policy: {} from ric: {}", policy.id(), policy.ric().name(), e);
122         return Mono.empty();
123     }
124 }