<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-sleuth</artifactId>
</dependency>


  

@Bean
public Sampler defaultSampler()
{
return Sampler.ALWAYS_SAMPLE;
}


  

package com.lidihuo.microservices.netflixzuulapigatewayserver;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.netflix.zuul.EnableZuulProxy;
import org.springframework.context.annotation.Bean;
import brave.sampler.Sampler;
@SpringBootApplication
@EnableDiscoveryClient
@EnableZuulProxy
public class NetflixZuulApiGatewayServerApplication 
{
public static void main(String[] args) 
{
SpringApplication.run(NetflixZuulApiGatewayServerApplication.class, args);
}
//creating a bean
@Bean
//creating a sampler called 
public Sampler defaultSampler()
{
return Sampler.ALWAYS_SAMPLE;
}
}


  

<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-sleuth</artifactId>
</dependency>


  

package com.lidihuo.microservices.currencyexchangeservice;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.context.annotation.Bean;
import brave.sampler.Sampler;
@SpringBootApplication
@EnableDiscoveryClient
public class CurrencyExchangeServiceApplication 
{
public static void main(String[] args) 
{
SpringApplication.run(CurrencyExchangeServiceApplication.class, args);
}
@Bean
//creating a sampler called always sampler
public Sampler defaultSampler()
{
return Sampler.ALWAYS_SAMPLE;
}
}


  

<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-sleuth</artifactId>
</dependency>


  

package com.lidihuo.microservices.currencyconversionservice;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;
import org.springframework.context.annotation.Bean;
import brave.sampler.Sampler;
@SpringBootApplication
@EnableFeignClients("com.lidihuo.microservices.currencyconversionservice")
@EnableDiscoveryClient
public class CurrencyConversionServiceApplication 
{
public static void main(String[] args) 
{
SpringApplication.run(CurrencyConversionServiceApplication.class, args);
}
@Bean
//creating a sampler called always sampler
public Sampler defaultSampler()
{
return Sampler.ALWAYS_SAMPLE;
}
}


  

package com.lidihuo.microservices.currencyexchangeservice;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.core.env.Environment;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
@SpringBootApplication
@RestController 
public class CurrencyExchangeController 
{
private Logger logger=LoggerFactory.getLogger(this.getClass());
@Autowired
private Environment environment;
@Autowired
private ExchangeValueRepository repository;
@GetMapping("/currency-exchange/from/{from}/to/{to}")      //where {from} and {to} are path variable
public ExchangeValue retrieveExchangeValue(@PathVariable String from, @PathVariable String to)   //from map to USD and to map to INR
{       
ExchangeValue exchangeValue = repository.findByFromAndTo(from, to);
//setting the port
exchangeValue.setPort(Integer.parseInt(environment.getProperty("local.server.port")));
logger.info("{}", exchangeValue);
return exchangeValue;
}
}


  

package com.lidihuo.microservices.currencyconversionservice;
import java.math.BigDecimal;
import java.util.HashMap;
import java.util.Map;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
@RestController
public class CurrencyConversionController 
{
private Logger logger=LoggerFactory.getLogger(this.getClass());
@Autowired
private CurrencyExchangeServiceProxy proxy;
@GetMapping("/currency-converter/from/{from}/to/{to}/quantity/{quantity}") //where {from} and {to} represents the column 
//returns a bean back
public CurrencyConversionBean convertCurrency(@PathVariable String from, @PathVariable String to, @PathVariable BigDecimal quantity)
{
//setting variables to currency exchange service
Map<String, String> uriVariables=new HashMap<>();
uriVariables.put("from", from);
uriVariables.put("to", to);
//calling the currency exchange service
ResponseEntity<CurrencyConversionBean> responseEntity=new RestTemplate().getForEntity("http://localhost:8000/currency-exchange/from/{from}/to/{to}", CurrencyConversionBean.class, uriVariables);
CurrencyConversionBean response=responseEntity.getBody();
//creating a new response bean and getting the response back and taking it into Bean
return new CurrencyConversionBean(response.getId(), from, to, response.getConversionMultiple(), quantity, quantity.multiply(response.getConversionMultiple()), response.getPort());
}
//mapping for currency-converter-feign service
@GetMapping("/currency-converter-feign/from/{from}/to/{to}/quantity/{quantity}") //where {from} and {to} represents the column 
//returns a bean 
public CurrencyConversionBean convertCurrencyFeign(@PathVariable String from, @PathVariable String to, @PathVariable BigDecimal quantity)
{
CurrencyConversionBean response=proxy.retrieveExchangeValue(from, to);
logger.info("{}", response);
//creating a new response bean
//getting the response back and taking it into Bean
return new CurrencyConversionBean(response.getId(), from, to, response.getConversionMultiple(), quantity, quantity.multiply(response.getConversionMultiple()), response.getPort());
}
}