Aspect I/O Method handler

Catch and handle or just log method's I/O/Exceptions

This is convinient input/output handler & logger. You can use it to handle and/or log any input and/or output from any method. You can also use this module as Request/Response logger for any controller or REST controller or any other purpose.

Module is compatible with Spring 5, you can use it in any from your projects (not only Spring ones) but also you can use it with Spring 5 and org.springframework.http.ResponseEntity class

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Install

Install from sources.

Current version is 1.0.1-SNAPSHOT. Version 1.0.1 Stable will be added to Maven Central.

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Overview

To use this module just simply add a @Logger annotation to your function/method/clousure or rest controller method as below.

class MyController{

    @Logger  // <- add this annotation to start logging method's input and output
    public ResponseEntity<WalletResponseDto> method(){}
    
}

You can also set some additional options and customize handling behaviour or even set up your own I/O handller.

class MyController{    
    @Logger(
            logResponseDurationTime = true,
            logRequestTime = true,
            timeZone = "UTC",
            includeStackTrace = true,
            filterStackTraceToPackage = "com.github.hadasbro.jlogger",
            logOnlyOnRequestValue = "userId:350",
            logTypes = {Logger.TYPE.REQUEST, Logger.TYPE.RESPONSE}
            loggerHandler = MyOwnhandler.class
    
    )
    public ResponseEntity<WalletResponseDto> method(){}
}

Function/method Input/Request should implement interface LoggableRequest or, if you use Spring Framework 5 - ResponseEntity

Function/method Output/Response should implement interface LoggableResponse;

Custom logger/handler should implement interface LoggerHandler;

If you want to catch function/method Exception you should implement interface LoggableException;

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Options

If you don't specify any additional options, module will be working as a simple I/O logger, so every method input and output will be logged to log as "info". You can also customize this behaviour and also set up your own handler as below.

1. logResponseDurationTime [ default: true ] - add/log duration (e.g. for REST controller this is gonna be just response time).

   @Logger(logResponseDurationTime = true)

2. logRequestTime [ default: true ] - add request/input datetime to log.

   @Logger(logResponseDurationTime = true)

3. timeZone [ default: "UTC" ] - set up timezone for request/input, to be loggeg/handled.

   @Logger(timeZone = "Europe/Warsaw")

4. includeStackTrace [ default: false ] - add stack trace to log/handler.

   @Logger(includeStackTrace = true)

5. filterStackTraceToPackage [ default: not settled, no limit ] - limit stack trace log to wanted package only.

   @Logger(filterStackTraceToPackage = "org.bitbucket.slawekhaa")

6. logOnlyOnRequestValue - handle/log input only if method/function contains param "param" and INPUT.param == value

   // log or handle only if Request/Input contains param userId and userId == 250, otherwise ommit
   @Logger(logOnlyOnRequestValue = "userId:350")

   You can use this option to log in your REST controller request - responses conditionally, only if input contains required parameter and value*

7. logTypes - handle/log only wanted actions (request, response, exception, all of them or only specific ones)

   // log or handle request and response, input and output
   @Logger(logTypes = {Logger.TYPE.REQUEST, Logger.TYPE.RESPONSE}) 
   
   // log or handle request/input only
   @LoggerlogTypes = Logger.TYPE.REQUEST)

8. loggerHandler - declare custom handler for all I/O action/log

   // use your own handler class
   @Logger(loggerHandler = MyOwnhandler.class) 
   
   // handler must implement interface LoggerHandler for example:
   public class MyOwnhandler implements LoggerHandler {
   
       private static String JOIN_SEPARATOR = " | ";
   
       private StringBuilder logResult = new StringBuilder();
   
       // this method will be called first, at the beginnig of Handler creation
       // this is kind of constructor, you can use this method to init your handler
       @Override
       public void init() {}
   
       // this method will be callest last, finally when module finish work
       // this is kind of destructor, you can use this method to finish work, e.g. to log result etc.
       @Override
       public void end() {
           // log to database
           StringUtils.strip(logResult.toString(), JOIN_SEPARATOR);
       }
   
       // this method will be called on request/input and will have an input object injested as a parameter
       @Override
       public void logRequest(LoggableRequest request, LoggerDetails loggerDetails) {
           logResult.append(" request: ").append(request).append(JOIN_SEPARATOR);
       }
   
       // this method will be called on response/output and will have an output object injested as a parameter
       @Override
       public void logResponse(LoggableResponse response, LoggerDetails loggerDetails) {
       
           logResult.append(" response: ").append(response).append(JOIN_SEPARATOR);
       
           if(!loggerDetails.getStackTrace().equals("")) {
               logResult.append(" trace: ").append(loggerDetails.getStackTrace());
           }
       }
   }

   Above handler class is a simple REST logger, every request & response handled by REST controller methods which are marked as @Logger(loggerHandler = MyOwnhandler.class) will be logged into a log.*

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Real example

This is REST controller/service logger example. Request (contaigning userId == 350) and response for method MyRestController::create will be logged to DB automatically.

package org.bitbucket.slawekhaa;

public class UserDto {

    public Integer id;
    public String name;
    
    public String toString(){
        return "id: " + id + ", name" + name;
    }
}

public class Response {

    public Integer status;
    public String message;
    
    Response(Integer status, String message) {
        this.status  = status;
        this.message  = message;
    }
    public String toString(){
        return "status:" + status + ", message: " + message;
    }
}

// example of request:
// {"id":1,"name":"super user}

@RestController
@RequestMapping("/rest/")
class MyRestController {

    @Logger(
        logResponseDurationTime = true,
        logRequestTime = true,
        includeStackTrace = true,
        filterStackTraceToPackage = "org.bitbucket.slawekhaa",
        logOnlyOnRequestValue = "userId:350",
        logTypes = Logger.TYPE.ALL, 
        loggerHandler = MyOwnhandler.class

    )
    @RequestMapping(value="create", method = RequestMethod.POST)
    public ResponseEntity<? extends Response> create(@RequestBody UserDto user) {

            // ... do some stuff
            return ResponseEntity.ok(new Response(1, "OK"));

    }
    
}

Result: every request which contains parameter userId == 350 and corresponding response for service MyRestController::test will be catched and handled by MyOwnhandler and logged in to the DB including stack trace limitd to package org.bitbucket.slawekhaa.

2019-04-01 12:00:28 request: [id: 1, name: super user] | response: [status: 1, message: OK] | duration: 245ms | trace:  ... -> MyRestController.create()

Todo, future releases

New interceptors and handler types.

enum TYPE{
    ALL,
    REQUEST,
    RESPONSE,
    ERROR,  // TODO
    TRACE   // TODO
}

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Authors

• Slawomir Hadas - author - Github