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Feign的负载均衡

Feign封装了Ribbon,所以也可以使用Ribbon负载均衡

全局：

配置类中注入负载均衡规则：随机，什么都不配置默认使用轮询

@Configurationpublic class RestTemplateConfig {    @Bean    public RandomRule randomRule(){        return new RandomRule();    }}

启动之后能看到结果

{"id":1,"orderNo":"order01","orderAddress":"address","totalPrice":200,"productList":[{"id":1,"name":"产品1-7073","num":1,"price":100},{"id":2,"name":"产品2-7073","num":2,"price":200},{"id":3,"name":"产品2-7073","num":3,"price":300}]}

{"id":1,"orderNo":"order01","orderAddress":"address","totalPrice":200,"productList":[{"id":1,"name":"产品1-7074","num":1,"price":100},{"id":2,"name":"产品2-7074","num":2,"price":200},{"id":3,"name":"产品2-7074","num":3,"price":300}]}

返回的数据显示，7073和7074两个服务随机请求，注意看“产品2-7073”和“产品2-7074”

局部

配置:

service-provider:    ribbon:        NFLoadBalancerRuleClassName: com.netflix.loadbalancer.RandomRule

Feign的请求传参

GET

使用@Pathvariable和@RequestParam注解接收参数

还是使用service-provider做演示，方便起见就不搞集群了。

增加一个根据ID查询产品信息的接口

ProductServiceImpl.java

@Override    public Product selectProductById(Long id) {        return new Product(id,"产品"+id+"-7073",1,new BigDecimal("100"));    }

ProductController.java

@GetMapping(value = "getProductsById/{id}")    public Product getProductsById(@PathVariable("id") Long id){        return productService.selectProductById(id);    }

然后是consumer-service-feign-7100，增加一个接口

ProductService.java

@GetMapping(value = "/provider/getProductsById/{id}")    Product getProductsById(@PathVariable("id") Long id);

OrderServiceImpl.java

@Override    public Order getById(Long id) {        return new Order(id,"order01","address",new BigDecimal("200"), Collections.singletonList(productService.getProductsById(id)));    }

OrderController.java

@GetMapping(value = "getById/{id}")    public Order getById(@PathVariable("id") Long id){        return orderService.getById(id);    }

POST

使用@requestBody注解接收参数

还是使用service-provider做演示,增加了一个POST根据ID获取和添加Product的接口

ProductServiceImpl.java

@Override    public Product selectProductByIdWithPost(Long id) {        return new Product(id,"产品"+id+"-7073",1,new BigDecimal("100"));    }    @Override    public Map
   
     createProduct(Product product) {        System.out.println("product = " + product);        Map
    
      result = new HashMap<>(2);        result.put("code","200");        result.put("message","success");        return result;    }
    
   

ProductController.java

@PostMapping(value = "getProductsByIdWithPost")    public Product selectProductByIdWithPost(@RequestBody Product product){        return productService.selectProductByIdWithPost(product.getId());    }    @PostMapping(value = "create")    public Map
   
     getProductsById(@RequestBody Product product){        return productService.createProduct(product);    }
   

然后是consumer-service-feign-7100，增加两个对应的接口

ProductService.java

@PostMapping(value = "/provider/getProductsByIdWithPost")    Product selectProductByIdWithPost(Product product);    @PostMapping(value = "/provider/create")    Map
   
     createProduct(Product product);
   

OrderServiceImpl.java

@Override    public Order selectProductByIdWithPost(Product product) {        return new Order(product.getId(),"order01","address",new BigDecimal("200"), Collections.singletonList(productService.selectProductByIdWithPost(product)));    }    @Override    public Map
   
     createProduct(Product product) {        return productService.createProduct(product);    }
   

OrderController.java

@PostMapping(value = "getProductsByIdWithPost")    public Order selectProductByIdWithPost(@RequestBody Product product){        return orderService.selectProductByIdWithPost(product);    }    @PostMapping(value = "create")    public Map
   
     getProductsById(@RequestBody Product product){        return orderService.createProduct(product);    }
   

测试样例

POST http://localhost:7100/order/getProductsByIdWithPostContent-Type: application/json{"id": 2}###POST http://localhost:7100/order/createContent-Type: application/json{"id": 2,"name": "name2"}