Logback: Logging JSON doesn't happen

Question

Here is my appender for writing logs to file (part of logback.xml):

<appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
    <file>logs/ps_gate_server.log</file>
    <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
    <Pattern>%d{dd-MM-yyyy} %d{HH:mm:ss.SSS} [%-19.19t] [%-5p] [%-1.40X{OperationName};%-1.10X{ClientID};%-1.20X{PayID}] %m%n </Pattern>
    </encoder> 
    <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
        <FileNamePattern>logs/ps_gate_server.%d{yyyy-MM-dd}.%i.log.zip</FileNamePattern>
        <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
           <!-- or whenever the file size reaches 100MB -->
           <maxFileSize>100MB</maxFileSize>
        </timeBasedFileNamingAndTriggeringPolicy>
    </rollingPolicy>
</appender>

As seen, my encoder is ch.qos.logback.classic.encoder.PatternLayoutEncoder and everything works. I need to convert my logging to JSON format. For this I change my encoder to net.logstash.logback.encoder.LogstashEncoder:

<appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
    <file>logs/ps_gate_server.log</file>
    <encoder class="net.logstash.logback.encoder.LogstashEncoder">
    <Pattern>%d{dd-MM-yyyy} %d{HH:mm:ss.SSS} [%-19.19t] [%-5p] [%-1.40X{OperationName};%-1.10X{ClientID};%-1.20X{PayID}] %m%n </Pattern>
    </encoder> 
    <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
        <FileNamePattern>logs/ps_gate_server.%d{yyyy-MM-dd}.%i.log.zip</FileNamePattern>
        <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
        <!-- or whenever the file size reaches 100MB -->
        <maxFileSize>100MB</maxFileSize>
    </timeBasedFileNamingAndTriggeringPolicy>
    </rollingPolicy>
</appender>

Then, when the program starts, the program does not create the file ps_gate_server.log. If someone knows, prompt please. All necessary jars are there.

Answer 1

Ensure you have all necessary dependencies for logback, minimum set will be:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.mycompamy</groupId>
    <artifactId>logback-test</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-core</artifactId>
            <version>1.1.7</version>
        </dependency>
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.1.7</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.21</version>
        </dependency>
        <dependency>
            <groupId>net.logstash.logback</groupId>
            <artifactId>logstash-logback-encoder</artifactId>
            <version>4.7</version>
        </dependency>
    </dependencies>
</project>

also ensure, that you have properly configured logback.xml, next example works well:

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <appender name="sout" class="ch.qos.logback.core.ConsoleAppender">
        <layout class="ch.qos.logback.classic.PatternLayout">
            <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
        </layout>
    </appender>
    <appender name="file" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <file>logs/ps_gate_server.log</file>
        <encoder class="net.logstash.logback.encoder.LogstashEncoder">
            <Pattern>%d{dd-MM-yyyy} %d{HH:mm:ss.SSS} [%-19.19t] [%-5p] [%-1.40X{OperationName};%-1.10X{ClientID};%-1.20X{PayID}] %m%n </Pattern>
        </encoder>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <FileNamePattern>logs/ps_gate_server.%d{yyyy-MM-dd}.%i.log.zip</FileNamePattern>
            <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <!-- or whenever the file size reaches 100MB -->
                <maxFileSize>100MB</maxFileSize>
            </timeBasedFileNamingAndTriggeringPolicy>
        </rollingPolicy>
    </appender>

    <root level="info">
        <appender-ref ref="file" />
        <appender-ref ref="sout" />
    </root>
</configuration>