Spring webclient testing with okhttp3 Mockwebserver - spring-boot

Question

I am unable to moock webclient
WebClientConfig.java
public #Bean("oauthWebClient") WebClient oauthWebClient() {
return WebClient.builder()
.clientConnector(new ReactorClientHttpConnector(
HttpClient.create().option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 1000)
.doOnConnected(connection -> connection.addHandlerLast(new ReadTimeoutHandler(10))
.addHandlerLast(new WriteTimeoutHandler(10)))))
.filter(logOAuthResponse()).baseUrl(oauthTokenUrl)
.defaultHeaders(headers -> {
headers.setBasicAuth(secretHeaderValue);
headers.add(HttpHeaders.CONTENT_TYPE, MediaType.APPLICATION_FORM_URLENCODED_VALUE);
})
.defaultUriVariables(oauthUriVariables)
.build();
}
serviceUti.java
package com.test.stats.volts.busops.utils;
import java.util.Map;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.retry.annotation.Recover;
import org.springframework.retry.annotation.Retryable;
import org.springframework.stereotype.Component;
import org.springframework.web.reactive.function.client.WebClient;
import org.springframework.web.reactive.function.client.WebClientRequestException;
import org.springframework.web.reactive.function.client.WebClientResponseException;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;
import com.test.stats.volts.busops.exception.VoltsDataAccessException;
import com.test.stats.volts.busops.exception.MtnDataAccessNotRespondingException;
import com.test.stats.volts.busops.exception.VoltsDataAcessException;
import com.test.stats.volts.busops.exception.UnableToGetOAuthTokenException;
#Component("voltsDataAccessServiceUtil")
public class ServiceUtil {
private static final Logger logger = LoggerFactory.getLogger(ServiceUtil.class);
#Autowired
#Qualifier("voltsDataAccessWebClient")
WebClient voltsDataAccessClient;
#Autowired
#Qualifier("oauthWebClient")
WebClient oauthClient;
#Value("${volts.dataaccess.end.point.save-meeting}")
private String saveMeetingEndPoint;
#Value("${volts.dataaccess.oauth.header-key.name}")
private String oauthHeaderKeyName;
#Value("${volts.dataccess.oauth.response.token.key-name}")
private String oauthResponseTokenKeyName;
#Value("#{${volts.dataaccess.api.endpoints.default.uri-variables}}")
private Map<String, String> voltsDataAccessUriVariables;
#Autowired
ObjectMapper mapper;
#Value("#{${volts.dataaccess.oauth.uri-variables}}")
private Map<String, String> oauthUriVariables;
#Value("${volts.dataaccess.oauth.scope}")
private String oauthScope;
#Value("${volts.dataaccess.oauth.grant_type}")
private String grantType;
#Value("${volts.dataaccess.oauth.secret.header-name}")
private String secretHeaderName;
#Value("${volts.dataaccess.oauth.secret.header-value}")
private String secretHeaderValue;
#Value("${volts.dataaccess.end.point.fetch-meeting}")
private String fetchMeetingEndPoint;
#Value("${volts.dataaccess.query.param.api-key-value}")
private String apiKey;
#Retryable(maxAttempts = 2)
public String postOAuthToken() throws VoltsDataAccessException {
try {
String respEntity = oauthClient.post()
.uri(uriBuilder -> uriBuilder.queryParam("scope", oauthScope).queryParam("grant_type", grantType)
.build())
.headers(headers -> headers.setBasicAuth(secretHeaderValue))
.retrieve()
.bodyToMono(String.class)
.block();
if (respEntity == null)
throw new UnableToGetOAuthTokenException(
"Exception while fetching OAUthToken as response from OAUth service is null resposne body");
try {
return mapper.readValue(respEntity, ObjectNode.class).get(oauthResponseTokenKeyName).asText();
} catch (JsonProcessingException e) {
logger.error("Exception while pasring token from Oauth ", e);
throw new UnableToGetOAuthTokenException(
"Exception while fetching OAUthToken as response from OAUth service is null resposne body");
}
} catch (WebClientRequestException e) {
logger.error("Request Exception to OAUth: message {}", e.getMessage(), e);
logger.error("", e);
throw new VoltsDataAccessException(e.getMessage(), HttpStatus.REQUEST_TIMEOUT.value());
}
catch (WebClientResponseException e) {
throw new VoltsDataAccessException(e.getMessage(), e.getRawStatusCode());
}
}
#Retryable(value = VoltsDataAcessException.class)
public ResponseEntity<VoltsResp> postSaveMeetingDetails(SaveVoltsReq voltsReq)
throws VoltsDataAcessException {
try {
ResponseEntity<VoltsResp> resp = voltsDataAccessClient.post()
.uri(saveMeetingEndPoint, uri -> uri.queryParam("apikey", apiKey).build())
.headers(headers -> headers.setBearerAuth(postOAuthToken()))
.contentType(MediaType.APPLICATION_JSON).bodyValue(voltsReq).retrieve()
.toEntity(VoltsResp.class).block();
return resp;
} catch (WebClientRequestException e) {
throw new VoltsDataAcessException(e.getMessage(), HttpStatus.REQUEST_TIMEOUT.value());
} catch (WebClientResponseException e) {
throw new VoltsDataAcessException(e.getMessage(), e.getRawStatusCode());
}
}
}
My test classs
WebClienrTests.java
import static org.assertj.core.api.Assertions.assertThat;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.boot.test.mock.mockito.MockBean;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.web.reactive.function.client.WebClient;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.test.stats.volts.busops.config.WebClientConfig;
import com.test.stats.volts.busops.utils.ServiceUtil;
import okhttp3.mockwebserver.MockResponse;
import okhttp3.mockwebserver.MockWebServer;
#SpringBootTest(classes = { ServiceUtil.class, WebClientConfig.class,
ObjectMapper.class })
#RunWith(SpringRunner.class)
class ServiceUtilTests {
public static MockWebServer mockServer = new MockWebServer();
#MockBean
WebClientConfig webClientCondfig;
#Autowired
ServiceUtil serviceUtil;
#MockBean(name = "oauthWebClient")
WebClient oauthClient;
#MockBean(name = "voltsDataAccessWebClient")
WebClient voltsDataAccessWebClient;
#BeforeEach
void startMockServer() throws Exception {
mockServer.start(9090);
oauthClient = WebClient.create(mockServer.url("/").url().toString());
}
#AfterEach
void stopMockServer() throws Exception {
mockServer.shutdown();
}
#Test
void testPostOAuth() throws Exception {
mockServer.enqueue(new MockResponse().setResponseCode(200).setBody("OAuthToken"));
String expected = serviceUtil.postOAuthToken();
assertThat(expected).isNotNull().isEqualTo("OAuthToken");
}
}
When I run above test I get this error
java.lang.NullPointerException:
At postAuthToken() while setting headers .headers(headers -> headers.setBasicAuth(secretHeaderValue))
Please help on how to mock whole thing