cff8160c3e026c86bae3c846415a879c73e4c5af
[dcaegen2/collectors/hv-ves.git] / sources / hv-collector-health-check / src / main / kotlin / org / onap / dcae / collectors / veshv / healthcheck / factory / HealthCheckApiServer.kt
1 /*
2  * ============LICENSE_START=======================================================
3  * dcaegen2-collectors-veshv
4  * ================================================================================
5  * Copyright (C) 2018-2019 NOKIA
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 package org.onap.dcae.collectors.veshv.healthcheck.factory
21
22 import io.netty.handler.codec.http.HttpResponseStatus
23 import org.onap.dcae.collectors.veshv.healthcheck.api.HealthDescription
24 import org.onap.dcae.collectors.veshv.healthcheck.api.HealthState
25 import org.onap.dcae.collectors.veshv.healthcheck.ports.PrometheusMetricsProvider
26 import org.onap.dcae.collectors.veshv.utils.NettyServerHandle
27 import org.onap.dcae.collectors.veshv.utils.ServerHandle
28 import org.onap.dcae.collectors.veshv.utils.logging.Logger
29 import reactor.core.publisher.Flux
30 import reactor.core.publisher.Mono
31 import reactor.netty.http.server.HttpServer
32 import reactor.netty.http.server.HttpServerRequest
33 import reactor.netty.http.server.HttpServerResponse
34 import java.net.SocketAddress
35 import java.util.concurrent.atomic.AtomicReference
36
37 /**
38  * @author Jakub Dudycz <jakub.dudycz@nokia.com>
39  * @since August 2018
40  */
41 class HealthCheckApiServer(private val healthState: HealthState,
42                            private val monitoring: PrometheusMetricsProvider,
43                            private val listenAddress: SocketAddress) {
44
45     private val healthDescription: AtomicReference<HealthDescription> = AtomicReference(HealthDescription.STARTING)
46
47     fun start(): Mono<ServerHandle> = Mono.defer {
48         healthState().subscribe(healthDescription::set)
49         HttpServer.create()
50                 .tcpConfiguration {
51                     it.addressSupplier { listenAddress }
52                             .doOnUnbound { logClose() }
53                 }
54                 .route { routes ->
55                     routes.get("/health/ready", ::readinessHandler)
56                     routes.get("/health/alive", ::livenessHandler)
57                     routes.get("/monitoring/prometheus", ::monitoringHandler)
58                 }
59                 .bind()
60                 .map { NettyServerHandle(it) }
61
62     }
63
64     private fun readinessHandler(_req: HttpServerRequest, resp: HttpServerResponse) =
65             healthDescription.get().run {
66                 logger.debug { "Component status: $status, $message" }
67                 resp.status(status.httpResponseStatus.number).sendString(Flux.just(status.toString(), "\n", message))
68             }
69
70     private fun livenessHandler(_req: HttpServerRequest, resp: HttpServerResponse) =
71             resp.status(HttpResponseStatus.NOT_IMPLEMENTED).sendString(Mono.just("Not implemented yet"))
72
73
74     private fun monitoringHandler(_req: HttpServerRequest, resp: HttpServerResponse) =
75             resp.sendString(monitoring.lastStatus())
76
77     private fun logClose() {
78         logger.info { "Health Check API closed" }
79     }
80
81     companion object {
82         private val logger = Logger(HealthCheckApiServer::class)
83
84     }
85
86 }