rest-services/dmaap-client/src/main/java/org/onap/dcaegen2/services/sdk/rest/services/dmaap/client/impl/MessageRouterSubscriberImpl.java

   1 /*
   2  * ============LICENSE_START====================================
   3  * DCAEGEN2-SERVICES-SDK
   4  * =========================================================
   5  * Copyright (C) 2019-2021 Nokia. All rights reserved.
   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.onap.dcaegen2.services.sdk.rest.services.dmaap.client.impl;
  22
  23 import com.google.gson.Gson;
  24 import com.google.gson.JsonArray;
  25 import com.google.gson.JsonElement;
  26 import com.google.gson.JsonParser;
  27 import io.netty.handler.timeout.ReadTimeoutException;
  28 import io.vavr.collection.List;
  29 import io.vavr.control.Option;
  30 import org.jetbrains.annotations.NotNull;
  31 import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.HttpMethod;
  32 import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.HttpRequest;
  33 import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.HttpResponse;
  34 import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.ImmutableHttpRequest;
  35 import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.RxHttpClient;
  36 import org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.api.MessageRouterSubscriber;
  37 import org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.error.ClientErrorReason;
  38 import org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.error.ClientErrorReasonPresenter;
  39 import org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.error.ClientErrorReasons;
  40 import org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.model.ImmutableMessageRouterSubscribeResponse;
  41 import org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.model.MessageRouterSubscribeRequest;
  42 import org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.model.MessageRouterSubscribeResponse;
  43 import org.slf4j.Logger;
  44 import org.slf4j.LoggerFactory;
  45 import reactor.core.publisher.Mono;
  46
  47 import java.nio.charset.StandardCharsets;
  48
  49 import static org.onap.dcaegen2.services.sdk.rest.services.dmaap.client.impl.Commons.extractFailReason;
  50
  51 /**
  52  * @author <a href="mailto:piotr.jaszczyk@nokia.com">Piotr Jaszczyk</a>
  53  * @since March 2019
  54  */
  55 public class MessageRouterSubscriberImpl implements MessageRouterSubscriber {
  56     private final RxHttpClient httpClient;
  57     private final Gson gson;
  58     private final ClientErrorReasonPresenter clientErrorReasonPresenter;
  59     private static final Logger LOGGER = LoggerFactory.getLogger(MessageRouterSubscriberImpl.class);
  60
  61     public MessageRouterSubscriberImpl(RxHttpClient httpClient, Gson gson,
  62                                        ClientErrorReasonPresenter clientErrorReasonPresenter) {
  63         this.httpClient = httpClient;
  64         this.gson = gson;
  65         this.clientErrorReasonPresenter = clientErrorReasonPresenter;
  66     }
  67
  68     @Override
  69     public Mono<MessageRouterSubscribeResponse> get(MessageRouterSubscribeRequest request) {
  70         LOGGER.debug("Requesting new items from DMaaP MR: {}", request);
  71         return httpClient.call(buildGetHttpRequest(request))
  72                 .map(this::buildGetResponse)
  73                 .doOnError(ReadTimeoutException.class,
  74                         e -> LOGGER.error("Timeout exception occurred when subscribe items from DMaaP MR", e))
  75                 .onErrorResume(ReadTimeoutException.class, e -> createErrorResponse(ClientErrorReasons.TIMEOUT));
  76     }
  77
  78
  79     private @NotNull HttpRequest buildGetHttpRequest(MessageRouterSubscribeRequest request) {
  80         ImmutableHttpRequest.Builder requestBuilder = ImmutableHttpRequest.builder()
  81                 .method(HttpMethod.GET)
  82                 .url(buildSubscribeUrl(request))
  83                 .diagnosticContext(request.diagnosticContext().withNewInvocationId());
  84
  85         return Option.of(request.timeoutConfig())
  86                 .map(timeoutConfig -> requestBuilder.timeout(timeoutConfig.getTimeout()).build())
  87                 .getOrElse(requestBuilder::build);
  88     }
  89
  90     private @NotNull MessageRouterSubscribeResponse buildGetResponse(HttpResponse httpResponse) {
  91         final ImmutableMessageRouterSubscribeResponse.Builder builder =
  92                 ImmutableMessageRouterSubscribeResponse.builder();
  93         return httpResponse.successful()
  94                 ? builder.items(getAsJsonElements(httpResponse)).build()
  95                 : builder.failReason(extractFailReason(httpResponse)).build();
  96     }
  97
  98     private List<JsonElement> getAsJsonElements(HttpResponse httpResponse) {
  99         JsonArray bodyAsJsonArray = httpResponse
 100                 .bodyAsJson(StandardCharsets.UTF_8, gson, JsonArray.class);
 101
 102         return List.ofAll(bodyAsJsonArray).map(arrayElement -> JsonParser.parseString(arrayElement.getAsString()));
 103     }
 104
 105     private String buildSubscribeUrl(MessageRouterSubscribeRequest request) {
 106         return String.format("%s/%s/%s", request.sourceDefinition().topicUrl(), request.consumerGroup(),
 107                 request.consumerId());
 108     }
 109
 110     private Mono<MessageRouterSubscribeResponse> createErrorResponse(ClientErrorReason clientErrorReason) {
 111         String failReason = clientErrorReasonPresenter.present(clientErrorReason);
 112         return Mono.just(ImmutableMessageRouterSubscribeResponse.builder()
 113                 .failReason(failReason)
 114                 .build());
 115     }
 116 }