Feign Client Logging and connection timeout

Upasana | July 14, 2020 | 2 min read | 2,830 views

we will cover how to enable network http request logging, connection timeout, read timeout for requests generated by feign Clients in Spring Boot applications.

Logging levels

Feign provides the following logging levels for debugging/troubleshooting purpose:

NONE: No logging. This is the default behaviour.
BASIC: Log only the request method and URL and the response status code and execution time.
HEADERS: Log the basic information along with request and response headers.
FULL: Log the headers, body, and metadata for both requests and responses.

There are two ways we can configure the logging level for feign clients - using properties and using java configuration. Lets discuss them both, one by one.

The very first step is to enable DEBUG logging for FeignClient in spring boot application properties.

application.yml

logging.level.package-path.FooClient: DEBUG

Logging will not work without this configuration.

Using application properties

Using application.yml, we can configure different attributes for feign client - at individual level or at global default level.

application.yml - Per Feign client configuration

feign:
  client:
    config:
      name_of_your_feign_client:  (1)
        connectTimeout: 5000
        readTimeout: 5000
        loggerLevel: basic

1	This is the name of the Feign Client

If we want to set it across feign clients, we can configure default settings using following configuration:

application.yml - Default Feign client configuration

feign:
  client:
    config:
      default:  (1)
        connectTimeout: 5000
        readTimeout: 5000
        loggerLevel: basic

1	This setting will be used as default settings across feign clients.

Using Java Configuration

We can achieve the same thing using Java Configuration, all we need to do is to create a Configuration with Bean of type Logger.Level

FeignConfig.kt

@Configuration
class FeignConfig {

    @Bean
    fun feignLoggerLevel(): Logger.Level {
        return Logger.Level.FULL
    }
}

Now we can use the feign config in Feign Client annotation, as show below.

FooClient.kt

@FeignClient(value = "foo-client", url = "http://foo-bar.url", configuration = [FeignConfig::class])
interface FooClient {

    @RequestMapping(method = RequestMethod.GET, value = "/user")
    fun getAllUsers(): List<User>

}