gerrit.onap Code Review - dcaegen2/services/sdk.git/blob

   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.adapters.http;
  22
  23 import io.netty.handler.codec.http.HttpResponseStatus;
  24 import io.vavr.collection.HashSet;
  25 import io.vavr.collection.Stream;
  26 import io.vavr.control.Option;
  27 import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.config.RetryConfig;
  28 import org.onap.dcaegen2.services.sdk.rest.services.adapters.http.exceptions.RetryableException;
  29 import org.onap.dcaegen2.services.sdk.rest.services.model.logging.RequestDiagnosticContext;
  30 import org.slf4j.Logger;
  31 import org.slf4j.LoggerFactory;
  32 import reactor.core.publisher.Mono;
  33 import reactor.netty.http.client.HttpClient;
  34 import reactor.netty.http.client.HttpClient.ResponseReceiver;
  35 import reactor.netty.http.client.HttpClientRequest;
  36 import reactor.netty.http.client.HttpClientResponse;
  37 import reactor.util.retry.Retry;
  38 import reactor.util.retry.RetryBackoffSpec;
  39
  40 import java.util.stream.Collectors;
  41
  42 /**
  43  * @since 1.1.4
  44  */
  45 public class RxHttpClient {
  46
  47     private static final Logger LOGGER = LoggerFactory.getLogger(RxHttpClient.class);
  48     private final HttpClient httpClient;
  49     private RetryConfig retryConfig;
  50
  51     RxHttpClient(HttpClient httpClient) {
  52         this.httpClient = httpClient;
  53     }
  54
  55     RxHttpClient(HttpClient httpClient, RetryConfig retryConfig) {
  56         this(httpClient);
  57         this.retryConfig = retryConfig;
  58     }
  59
  60     public Mono<HttpResponse> call(HttpRequest request) {
  61         Mono<HttpResponse> httpResponseMono = response(request);
  62         return Option.of(retryConfig)
  63                 .map(rc -> retryConfig(rc, request.diagnosticContext()))
  64                 .map(httpResponseMono::retryWhen)
  65                 .getOrElse(() -> httpResponseMono);
  66     }
  67
  68     ResponseReceiver<?> prepareRequest(HttpRequest request) {
  69         final HttpClient simpleClient = httpClient
  70                 .doOnRequest((req, conn) -> logRequest(request.diagnosticContext(), req))
  71                 .doOnResponse((rsp, conn) -> logResponse(request.diagnosticContext(), rsp))
  72                 .headers(hdrs -> request.headers().forEach(hdr -> hdrs.set(hdr._1, hdr._2)));
  73
  74         final HttpClient theClient = Option.of(request.timeout())
  75                 .map(simpleClient::responseTimeout)
  76                 .getOrElse(simpleClient);
  77
  78         return prepareBody(request, theClient);
  79     }
  80
  81     private Mono<HttpResponse> response(HttpRequest request) {
  82         return prepareRequest(request)
  83                 .responseSingle((resp, content) -> mapResponse(request.url(), resp.status(), content));
  84     }
  85
  86     private Mono<HttpResponse> mapResponse(String url, HttpResponseStatus status, reactor.netty.ByteBufMono content) {
  87         return content.asByteArray()
  88                 .defaultIfEmpty(new byte[0])
  89                 .map(bytes -> new NettyHttpResponse(url, status, bytes))
  90                 .map(this::validatedResponse);
  91     }
  92
  93     private HttpResponse validatedResponse(HttpResponse response) {
  94         if (shouldRetry(response.statusCode())) {
  95             throw new RetryableException(response);
  96         }
  97         return response;
  98     }
  99
 100     private boolean shouldRetry(int code) {
 101         return Option.of(retryConfig)
 102                 .map(RetryConfig::retryableHttpResponseCodes)
 103                 .getOrElse(HashSet::empty)
 104                 .contains(code);
 105     }
 106
 107     private ResponseReceiver<?> prepareBody(HttpRequest request, HttpClient theClient) {
 108         if (request.body() == null) {
 109             return prepareBodyWithoutContents(request, theClient);
 110         } else {
 111             return request.body().length() == null
 112                     ? prepareBodyChunked(request, theClient)
 113                     : prepareBodyUnchunked(request, theClient);
 114         }
 115     }
 116
 117     private ResponseReceiver<?> prepareBodyChunked(HttpRequest request, HttpClient theClient) {
 118         return theClient
 119                 .headers(hdrs -> hdrs.set(HttpHeaders.TRANSFER_ENCODING_TYPE, HttpHeaders.CHUNKED))
 120                 .request(request.method().asNetty())
 121                 .send(request.body().contents())
 122                 .uri(request.url());
 123     }
 124
 125     private ResponseReceiver<?> prepareBodyUnchunked(HttpRequest request, HttpClient theClient) {
 126         return theClient
 127                 .headers(hdrs -> hdrs.set(HttpHeaders.CONTENT_LENGTH, request.body().length().toString()))
 128                 .request(request.method().asNetty())
 129                 .send(request.body().contents())
 130                 .uri(request.url());
 131     }
 132
 133     private ResponseReceiver<?> prepareBodyWithoutContents(HttpRequest request, HttpClient theClient) {
 134         return theClient
 135                 .request(request.method().asNetty())
 136                 .uri(request.url());
 137     }
 138
 139     private void logRequest(RequestDiagnosticContext context, HttpClientRequest httpClientRequest) {
 140         context.withSlf4jMdc(LOGGER.isDebugEnabled(), () -> {
 141             LOGGER.debug("Request: {} {} {}", httpClientRequest.method(), httpClientRequest.uri(),
 142                     httpClientRequest.requestHeaders());
 143             if (LOGGER.isTraceEnabled()) {
 144                 final String headers = Stream.ofAll(httpClientRequest.requestHeaders())
 145                         .map(entry -> entry.getKey() + "=" + entry.getValue())
 146                         .collect(Collectors.joining("\n"));
 147                 LOGGER.trace(headers);
 148             }
 149         });
 150     }
 151
 152     private void logResponse(RequestDiagnosticContext context, HttpClientResponse httpClientResponse) {
 153         context.withSlf4jMdc(LOGGER.isDebugEnabled(),
 154                 () -> LOGGER.debug("Response status: {}", httpClientResponse.status()));
 155     }
 156
 157     private RetryBackoffSpec retryConfig(RetryConfig retryConfig, RequestDiagnosticContext context) {
 158         return Retry
 159                 .fixedDelay(retryConfig.retryCount(), retryConfig.retryInterval())
 160                 .doBeforeRetry(retrySignal -> context.withSlf4jMdc(
 161                         LOGGER.isTraceEnabled(), () -> LOGGER.trace("Retry: {}", retrySignal)))
 162                 .filter(ex -> isRetryable(retryConfig, ex))
 163                 .onRetryExhaustedThrow((retryBackoffSpec, retrySignal) -> retrySignal.failure());
 164     }
 165
 166     private boolean isRetryable(RetryConfig retryConfig, Throwable ex) {
 167         return retryConfig.retryableExceptions()
 168                 .toStream()
 169                 .exists(clazz -> clazz.isAssignableFrom(ex.getClass()));
 170     }
 171 }