application.properties to application.yml _Application

莫道桑榆晚，为霞尚满天。这篇文章主要讲述application.properties to application.yml相关的知识，希望能为你提供帮助。
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https://howtodoinjava.com/spring-boot/configure-logging-application-yml/

Spring Boot Logging with application.ymlBy Lokesh Gupta | Filed Under: Spring Boot
Learn spring boot logging configuration via application.yml file in simple and easy to follow instructions. In the default structure of a Spring Boot web application, you can locate the application.yml file under the resources folder.
Read More: Spring Boot Logging with application.properties

Table of ContentsUnderstand default spring boot logging Set logging level Set logging pattern Set logging output to file Using active profiles to load environment specific logging configuration Color-coded logging output

Understand default spring boot loggingTo understand default spring boot logging, lets put logs in spring boot hello world example. Just to mention, there is no logging related configuration in application.yml file. If you see any configuration in downloaded application, please remove it.

private final Logger LOGGER = LoggerFactory.getLogger(this

.getClass());

@RequestMapping("/") public

String home(Map<
String, Object>
 model) {

LOGGER.debug("This is a debug message"

);

LOGGER.info("This is an info message"

);

LOGGER.warn("This is a warn message"

);

LOGGER.error("This is an error message"

);

model.put("message"

"HowToDoInJava Reader !!"

);

return "index"

}

Start the application. Access application at browser and verify log messages in console.

2017-03-02 23:33:51.318

INFO

3060 --- [nio-8080-exec-1

] c.h.app.controller.IndexController 
 
 
 
 
 
 : info log statement printed

2017-03-02 23:33:51.319

WARN

3060 --- [nio-8080-exec-1

] c.h.app.controller.IndexController 
 
 
 
 
 
 : warn log statement printed

2017-03-02 23:33:51.319

ERROR

3060 --- [nio-8080-exec-1

] c.h.app.controller.IndexController 
 
 
 
 
 
 : error log statement printed

Note down the observation that Default logging level is INFO – because debug log message is not present.
There is fixed default log message pattern which is configured in different base configuration files.

%clr{%d{yyyy-MM-dd HH:mm:ss.SSS}}{faint} %clr{${LOG_LEVEL_PATTERN}} %clr{${sys:PID}}{magenta} %clr{---}{faint} %clr{[%15.15t]}{faint} %clr{%-40.40c{1.}}{cyan} %clr{:}{faint} %m%n${sys:LOG_EXCEPTION_CONVERSION_WORD}

The above pattern print these listed log message parts with respective color coding applied:

Date and Time — Millisecond precision.
Log Level — ERROR, WARN, INFO, DEBUG or TRACE.
Process ID.
A — separator to distinguish the start of actual log messages.
Thread name — Enclosed in square brackets (may be truncated for console output).
Logger name — This is usually the source class name (often abbreviated).
The log message

Set logging levelWhen a message is logged via a Logger it is logged with a certain log level. In the application.yml file, you can define log levels of Spring Boot loggers, application loggers, Hibernate loggers, Thymeleaf loggers, and more. To set the logging level for any logger, add keys starting with logging.level.
Logging level can be one of one of TRACE, DEBUG, INFO, WARN, ERROR, FATAL, OFF. The root logger can be configured using logging.level.root.

logging:

level:

root: ERROR

org.springframework.web: ERROR

com.howtodoinjava: DEBUG

org.hibernate: ERROR

In above configuration, I upgraded log level for application classes to DEBUG (from default INFO). Now observe the logs:

2017-03-02 23:57:14.966

DEBUG

4092 --- [nio-8080-exec-1

] c.h.app.controller.IndexController 
 
 
 
 
 
 : debug log statement printed

2017-03-02 23:57:14.967

INFO

4092 --- [nio-8080-exec-1

] c.h.app.controller.IndexController 
 
 
 
 
 
 : info log statement printed

2017-03-02 23:57:14.967

WARN

4092 --- [nio-8080-exec-1

] c.h.app.controller.IndexController 
 
 
 
 
 
 : warn log statement printed

2017-03-02 23:57:14.967

ERROR

4092 --- [nio-8080-exec-1

] c.h.app.controller.IndexController 
 
 
 
 
 
 : error log statement printed

Set logging patternTo change the loging patterns, use logging.pattern.console and logging.pattern.file keys.

logging:

pattern:

console: %d{yyyy-MM-dd HH:mm:ss} - %msg%n

file: %d{yyyy-MM-dd HH:mm:ss} [%thread] %-5level %logger{36} - %msg%n

After changing console logging pattern in application, log statements are printed as below:

2017-03-03 12:59:13 - This is a debug message 2017-03-03 12:59:13 - This is an info message 2017-03-03 12:59:13 - This is a warn message 2017-03-03 12:59:13 - This is an error message

Set logging output to fileTo print the logs in file, use logging.file or logging.path key.

logging:

file: /logs/application-debug.log

Verify the logs in file.

2017-03-03 13:02:50.608

DEBUG

10424 --- [http-nio-8080-exec-1

] c.h.app.controller.IndexController 
 
 
 
 
 
 : This is a debug message

2017-03-03 13:02:50.608

INFO

10424 --- [http-nio-8080-exec-1

] c.h.app.controller.IndexController 
 
 
 
 
 
 : This is an info message

2017-03-03 13:02:50.608

WARN

10424 --- [http-nio-8080-exec-1

] c.h.app.controller.IndexController 
 
 
 
 
 
 : This is a warn message

2017-03-03 13:02:50.609

ERROR

10424 --- [http-nio-8080-exec-1

] c.h.app.controller.IndexController 
 
 
 
 
 
 : This is an error message

Using active profiles to load environment specific logging configurationIt is desirable to have multiple configurations for any application – where each configuration is specific to a particular runtime environment. In spring boot, you can achieve this by creating multiple application-{profile}.yml files in same location as application.yml file.
Profile specific keys always override the non-profile specific ones. If several profiles are specified, a last wins strategy applies.
If I have two environments for my application i.e. prod and dev. Then I will create two profile specific yml files.
application-dev.yml

logging:

file: logs/application-debug.log

pattern:

console:

"%d %-5level %logger : %msg%n"

file:

"%d %-5level [%thread] %logger : %msg%n"

level:

org.springframework.web: ERROR

com.howtodoinjava: DEBUG

org.hibernate: ERROR

application-prod.yml

logging:

file: logs/application-debug.log

pattern:

console:

"%d %-5level %logger : %msg%n"

file:

"%d %-5level [%thread] %logger : %msg%n"

level:

org.springframework.web: ERROR

com.howtodoinjava: INFO

org.hibernate: ERROR

To supply profile information to application, key spring.profiles.active is passed to runtime.

$ java -jar -Dspring.profiles.active=prod spring-boot-demo.jar

Color-coded logging outputIf your terminal supports ANSI, color output will be used to aid readability. You can set spring.output.ansi.enabled value to either ALWAYS, NEVER or DETECT.

spring:

output:

ansi:

enabled: DETECT

Color coding is configured using the %clr conversion word. In its simplest form the converter will color the output according to the log level.
【application.properties to application.yml】FATAL and ERROR – Red
WARN – Yellow
INFO, DEBUG and TRACE – Green
Drop me your questions in comments section.
Happy Learning !!
References:
Spring Boot – How to logging
Spring boot features – Logging