Logback layout for Google Structured logging

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Why?

• Google indexes logs - easies and faster to filter logs. See Using the Logs Explorer
• Aggregating logs by labels
• Log metrics
• Proper logging levels in the UI
• See this StackOverflow question

See structured logs.

Getting started

Maven:

<dependencies>
    <dependency>
        <groupId>io.github.aaabramov</groupId>
        <artifactId>glogging-core</artifactId>
        <version>0.1.0</version>
    </dependency>


    <dependency>
        <groupId>io.github.aaabramov</groupId>
        <artifactId>glogging-gson</artifactId>
        <!-- OR -->
        <!--<artifactId>glogging-jackson</artifactId>-->
        <version>0.1.0</version>
    </dependency>
</dependencies>

Gradle (Groovy):

implementation 'io.github.aaabramov:glogging-core:0.1.0'
implementation 'io.github.aaabramov:glogging-gson:0.1.0'
// OR 
// implementation 'io.github.aaabramov:glogging-jackson:0.1.0'

Gradle (Kotlin):

implementation("io.github.aaabramov:glogging-core:0.1.0")
implementation("io.github.aaabramov:glogging-gson:0.1.0")
// OR 
// implementation("io.github.aaabramov:glogging-jackson:0.1.0")

Sbt:

libraryDependencies ++= Seq(
  "io.github.aaabramov" % "glogging-core",
  "io.github.aaabramov" % "glogging-gson"
  //  OR
  //  "io.github.aaabramov" % "glogging-jackson"
).map(_ % "0.1.0")

Configuration example:

<configuration>
    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
        <encoder class="ch.qos.logback.core.encoder.LayoutWrappingEncoder">
            <layout class="io.github.aaabramov.glogging.GoogleLayout">

                <!-- You have a choice which JSON encoder to use. Or create your own via implementing JsonEncoder interface -->
                <json>io.github.aaabramov.glogging.JacksonEncoder</json>

                <!-- OR -->
                <!-- <json>io.github.aaabramov.glogging.GsonEncoder</json> -->

                <!-- Optionally append "${prefix}/loggerName" labels -->
                <appendLoggerName>true</appendLoggerName>

                <!-- Optionally configure prefix for labels -->
                <prefix>com.yourcompany</prefix>

                <!-- Provide message pattern you like. -->
                <!-- Note: there is no need anymore to log timestamps & levels to the message. Google will pick them up from specific fields. -->
                <pattern>%message %xException{10}</pattern>
            </layout>
        </encoder>
    </appender>

    <appender name="ASYNCSTDOUT" class="ch.qos.logback.classic.AsyncAppender">
        <appender-ref ref="STDOUT"/>
    </appender>

    <!--  Configure logging levels  -->
    <logger name="com.github" level="DEBUG"/>

    <root level="DEBUG">
        <appender-ref ref="ASYNCSTDOUT"/>
    </root>
</configuration>

Example output:

{"timestamp":{"seconds":1629642099,"nanos":659000000},"severity":"DEBUG","message":"debug","labels":{"io.github.aaabramov/name":"Andrii","io.github.aaabramov/loggerName":"io.github.aaabramov.glogging.App"}}
{"timestamp":{"seconds":1629642099,"nanos":659000000},"severity":"INFO","message":"info","labels":{"io.github.aaabramov/name":"Andrii","io.github.aaabramov/loggerName":"io.github.aaabramov.glogging.App"}}
{"timestamp":{"seconds":1629642099,"nanos":659000000},"severity":"WARN","message":"warn","labels":{"io.github.aaabramov/name":"Andrii","io.github.aaabramov/loggerName":"io.github.aaabramov.glogging.App"}}
{"timestamp":{"seconds":1629642099,"nanos":661000000},"severity":"ERROR","message":"error java.lang.RuntimeException: BOOM\n\tat io.github.aaabramov.glogging.App.main(App.java:22)","labels":{"io.github.aaabramov/name":"Andrii","io.github.aaabramov/loggerName":"io.github.aaabramov.glogging.App"}}
{"timestamp":{"seconds":1629642102,"nanos":661000000},"severity":"DEBUG","message":"debug","labels":{"io.github.aaabramov/name":"Andrii","io.github.aaabramov/loggerName":"io.github.aaabramov.glogging.App"}}
{"timestamp":{"seconds":1629642102,"nanos":661000000},"severity":"INFO","message":"info","labels":{"io.github.aaabramov/name":"Andrii","io.github.aaabramov/loggerName":"io.github.aaabramov.glogging.App"}}
{"timestamp":{"seconds":1629642102,"nanos":661000000},"severity":"WARN","message":"warn","labels":{"io.github.aaabramov/name":"Andrii","io.github.aaabramov/loggerName":"io.github.aaabramov.glogging.App"}}
{"timestamp":{"seconds":1629642102,"nanos":661000000},"severity":"ERROR","message":"error","labels":{"io.github.aaabramov/name":"Andrii","io.github.aaabramov/loggerName":"io.github.aaabramov.glogging.App"}}

Releasing

mvn versions:set -DnewVersion=X.Y.Z
mvn versions:commit
mvn clean javadoc:jar source:jar verify gpg:sign deploy
# Close & Release here https://s01.oss.sonatype.org/#stagingRepositories