async support missing in reactive redis connection

Question

I am learning to use spring webflux and as part of it i developed an application which uses Redis to save and retrieve data. But the problem i face is when the request tries to connect to redis i get following error :

{
  "timestamp": "2020-03-25T10:34:07.020+0000",
  "status": 500,
  "error": "Internal Server Error",
  "message": "Async support must be enabled on a servlet and for all filters involved in async request processing. This is done in Java code using the Servlet API or by adding \"<async-supported>true</async-supported>\" to servlet and filter declarations in web.xml.",
  "path": "/tax/lines/save/"
}

I have searched enough about this issue and dint find anything useful.

Here is my Redis configuration class:

@Configuration
@EnableAsync
public class RedisConfig {

    @Value("${vcap.services.redis.credentials.hostname:10.11.241.101}")
    private String host;

    @Value("${vcap.services.redis.credentials.port:36516}")
    private int port;
    @Bean
    public ReactiveRedisConnectionFactory reactiveRedisConnectionFactory() {
        return new LettuceConnectionFactory(host, port);
    }

    @Bean
    ReactiveRedisOperations<TaxDetails, TaxLine> redisOperations(ReactiveRedisConnectionFactory reactiveRedisConnectionFactory) {
        Jackson2JsonRedisSerializer<TaxDetails> serializer = new Jackson2JsonRedisSerializer<>(TaxDetails.class);
        Jackson2JsonRedisSerializer<TaxLine> serializer1 = new Jackson2JsonRedisSerializer<>(TaxLine.class);
        RedisSerializationContext.RedisSerializationContextBuilder<TaxDetails, TaxLine> builder = RedisSerializationContext
                .newSerializationContext(new StringRedisSerializer());
        RedisSerializationContext<TaxDetails, TaxLine> context = builder.key(serializer).value(serializer1).build();;
        ReactiveRedisTemplate<TaxDetails,TaxLine> template = new ReactiveRedisTemplate<>(reactiveRedisConnectionFactory,context);
        return template;
    }

}

Here is my redis look up class which actually fetches and saves data from redis

package com.sap.slh.tax.attributes.determination.springwebfluxdemo.lookup;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.ReactiveRedisOperations;
import org.springframework.stereotype.Service;

import com.sap.slh.tax.attributes.determination.springwebfluxdemo.model.RedisRepo;
import com.sap.slh.tax.attributes.determination.springwebfluxdemo.model.TaxDetails;
import com.sap.slh.tax.attributes.determination.springwebfluxdemo.model.TaxLine;
import com.sap.slh.tax.attributes.determination.springwebfluxdemo.util.JsonUtil;

import reactor.core.publisher.Flux;
import reactor.core.publisher.Mono;

@Service
public class RedisTaxLineLookUpService {
    private static final Logger log = LoggerFactory.getLogger(RedisTaxLineLookUpService.class);

    @Autowired
    private ReactiveRedisOperations<TaxDetails, TaxLine> redisOperations;

    public Flux<TaxLine> get(TaxDetails taxDetails) {

        log.info("going to call redis to fetch tax lines{}", JsonUtil.toJsonString(taxDetails));
        return redisOperations.keys(taxDetails).flatMap(redisOperations.opsForValue()::get);

    }

    public Mono<RedisRepo> set(RedisRepo redisRepo) {
        log.info("going to call redis to save tax lines{}", JsonUtil.toJsonString(redisRepo.getTaxDetails()));
        return redisOperations.opsForValue().set(redisRepo.getTaxDetails(), redisRepo.getTaxLine())
                .map(__ -> redisRepo);
    }

}

Controller :

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;

import com.sap.slh.tax.attributes.determination.springwebfluxdemo.model.RedisRepo;
import com.sap.slh.tax.attributes.determination.springwebfluxdemo.model.TaxDetails;
import com.sap.slh.tax.attributes.determination.springwebfluxdemo.model.TaxLine;
import com.sap.slh.tax.attributes.determination.springwebfluxdemo.service.TaxLineService;
import com.sap.slh.tax.attributes.determination.springwebfluxdemo.util.JsonUtil;

import reactor.core.publisher.Mono;

@RestController
public class TaxLinesDeterminationController {

    private static final Logger log = LoggerFactory.getLogger(TaxLinesDeterminationController.class);

    @Autowired
    private TaxLineService taxLineService;

    @PostMapping(value = "/tax/lines",consumes = MediaType.APPLICATION_JSON_VALUE,produces = MediaType.APPLICATION_JSON_VALUE)
    public Mono<TaxLine> determineTaxLines(@RequestBody(required = true) final TaxDetails request)
    {
        log.info("the request received is{}",JsonUtil.toJsonString(request));
        return taxLineService.determineTaxLines(request);   
    }

    @PostMapping(value = "/tax/lines/save",consumes = MediaType.APPLICATION_JSON_VALUE,produces = MediaType.APPLICATION_JSON_VALUE)
    public Mono<RedisRepo> saveTaxLines(@RequestBody(required = true) final RedisRepo request)
    {

        log.info("the request received is{}",JsonUtil.toJsonString(request));
        return taxLineService.saveTaxLines(request);    
    }
}

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.5.RELEASE</version>
        <relativePath /> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.sap.slh.tax.attributes.determination</groupId>
    <artifactId>springwebfluxdemo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>war</packaging>
    <name>springwebfluxdemo</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-amqp</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis-reactive</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-webflux</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>io.projectreactor</groupId>
            <artifactId>reactor-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.amqp</groupId>
            <artifactId>spring-rabbit-test</artifactId>
            <scope>test</scope>
        </dependency>
        <!-- https://mvnrepository.com/artifact/redis.clients/jedis -->
        <dependency>
            <groupId>redis.clients</groupId>
            <artifactId>jedis</artifactId>
        </dependency>
        <dependency>
            <groupId>com.sap.hcp.cf.logging</groupId>
            <artifactId>cf-java-logging-support-logback</artifactId>
            <version>2.2.3</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

Please help me identify the issue. Thanks in advance !

Answer 1

As per the suggesion of Yauhen Balykin, i have removed Tomcat dependency and also removed the packaging in the jar. now it works fine