Use structured log format in production by default

src/main/resources/logback.xml

@@ -1,20 +1,28 @@
 <configuration>
     <variable name="communicationLogLevel" value="${HTTP_COMMUNICATION_LOG_LEVEL:-INFO}"/>
-
+    <!--    GCP's structured log format-->
     <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
-        <if condition='property("LOG_FORMAT").equals("JSON")'>
-            <then>
-                <encoder class="net.logstash.logback.encoder.LogstashEncoder"/>
-            </then>
-            <else>
-                <withJansi>true</withJansi>
-                <encoder>
-                    <pattern>
-                        %cyan(%d{HH:mm:ss.SSS}) %gray([%thread]) %highlight(%-5level) %magenta(%logger{36}) - %msg%n
-                    </pattern>
-                </encoder>
-            </else>
-        </if>
+        <encoder class="net.logstash.logback.encoder.LoggingEventCompositeJsonEncoder">
+            <providers>
+                <timestamp>
+                    <fieldName>timestamp</fieldName>
+                </timestamp>
+                <loggerName/>
+                <logLevel>
+                    <fieldName>severity</fieldName>
+                </logLevel>
+                <message/>
+                <stackHash/>
+                <stackTrace>
+                    <throwableConverter class="net.logstash.logback.stacktrace.ShortenedThrowableConverter">
+                        <maxDepthPerThrowable>30</maxDepthPerThrowable>
+                        <maxLength>2048</maxLength>
+                        <shortenedClassNameLength>20</shortenedClassNameLength>
+                        <rootCauseFirst>true</rootCauseFirst>
+                    </throwableConverter>
+                </stackTrace>
+            </providers>
+        </encoder>
     </appender>
 
     <logger name="org.jooq" level="ERROR"/>