For some integration projects it is helpful to persist application logs in a relational database instead of a plain log file. In this article, I show how to configure a JDBC appender for Red Hat Fuse 7 running in an Apache Karaf environment. There are instructions that describe how to persist messagess with PostgreSQL. Instead, I will show how to setup a JDBC appender for Oracle Database 11g.
I have tested this procedure with Oracle Database 11g Express Edition. A major difference I found is with the table syntax and the fact that the Oracle Database 11g sequence and trigger were required to auto-generate the primary key. Hence, users of Oracle Database 11g should find this article useful.
1. Create an org.ops4j.datasource-oracleds.cfg file in the FUSE_HOME/etc folder with the following content:
databaseName=xe user=SYSTEM password=administrator dataSourceName=oracleds url=jdbc:oracle:thin:@192.168.1.10:1521/xe osgi.jdbc.driver.class=oracle.jdbc.OracleDriver
2. Install the Oracle driver from the Karaf terminal using the following command:
osgi:install -s wrap:mvn:com.oracle/ojdbc6/11.2.0.3
3. Install these features:
feature:install jdbc jndi pax-jdbc-oracle
4. Check service:list for the DataSourceFactory object:
karaf@root()> service:list DataSourceFactory [org.osgi.service.jdbc.DataSourceFactory] ----------------------------------------- osgi.jdbc.driver.class = oracle.jdbc.OracleDriver osgi.jdbc.driver.name = wrap_mvn_com.oracle_ojdbc6_11.2.0.3 osgi.jdbc.driver.version = 0.0.0 service.bundleid = 223 service.id = 259 service.scope = singleton Provided by : wrap_mvn_com.oracle_ojdbc6_11.2.0.3 (223) Used by: OPS4J Pax JDBC Config (239) [org.osgi.service.jdbc.DataSourceFactory] ----------------------------------------- osgi.jdbc.driver.class = oracle.jdbc.OracleDriver osgi.jdbc.driver.name = oracle service.bundleid = 237 service.id = 246 service.scope = singleton Provided by : OPS4J Pax JDBC Oracle Driver Adapter (237) Used by: OPS4J Pax JDBC Config (239)
5. Check service:list for the DataSource object:
karaf@root()> service:list DataSource [javax.sql.DataSource] ---------------------- databaseName = xe dataSourceName = oracleds felix.fileinstall.filename = file:/home/cpandey/NotBackedUp/Development/RedHat_Fuse_Folder/fuse7_2/fuse-karaf-7.2.0.fuse-720035-redhat-00001/etc/org.ops4j.datasource-oracleds.cfg osgi.jdbc.driver.class = oracle.jdbc.OracleDriver osgi.jndi.service.name = oracleds password = administrator pax.jdbc.managed = true service.bundleid = 239 service.factoryPid = org.ops4j.datasource service.id = 261 service.pid = org.ops4j.datasource.a6fadb91-16e5-43bb-8990-bbbaa553be8d service.scope = singleton url = jdbc:oracle:thin:@192.168.1.10:1521/xe user = SYSTEM Provided by : OPS4J Pax JDBC Config (239) Used by: OPS4J Pax Logging - Log4j v2 (8)
6. Create the event table:
CREATE TABLE "SYSTEM"."EVENTS"
( "EVENT_ID" NUMBER(10,0) NOT NULL ENABLE,
"EVENT_DATE" TIMESTAMP (0),
"EVENT_LEVEL" VARCHAR2(5),
"EVENT_SOURCE" VARCHAR2(128),
"EVENT_THREAD_ID" VARCHAR2(128),
"EVENT_MESSAGE" VARCHAR2(1024),
CONSTRAINT "EVENT_ID_PK" PRIMARY KEY ("EVENT_ID"));
The table create statement can also be executed from the Karaf terminal:
karaf@root()> jdbc:execute oracleds 'CREATE TABLE "EVENTS" ("EVENT_ID" NUMBER(10,0) NOT NULL ENABLE, "EVENT_DATE" TIMESTAMP (0), "EVENT_LEVEL" VARCHAR2(5), "EVENT_SOURCE" VARCHAR2(128), "EVENT_THREAD_ID" VARCHAR2(128), "EVENT_MESSAGE" VARCHAR2(1024), CONSTRAINT "EVENT_ID_PK" PRIMARY KEY ("EVENT_ID"))'
I find doing that way is very useful. It would also test whether the datasource is set correctly or not.
7. In the database, we need to create a sequence and trigger.
Sequence:
create sequence events_seq start with 1 increment by 1;
Trigger:
create or replace trigger events_seq_tr before insert on events for each row when (new.event_id is null) begin select events_seq.nextval into :new.event_id from dual; END;
Note the terminating semicolon in the trigger.
8. In FUSE_HOME/etc/org.ops4j.pax.logging.cfg, set the following:
log4j2.rootLogger.appenderRef.JdbcAppender.ref = JdbcAppender log4j2.appender.jdbc.type = JDBC log4j2.appender.jdbc.name = JdbcAppender log4j2.appender.jdbc.tableName = EVENTS log4j2.appender.jdbc.cs.type = DataSource log4j2.appender.jdbc.cs.jndiName = osgi:service/oracleds log4j2.appender.jdbc.c1.type = Column log4j2.appender.jdbc.c1.name = EVENT_DATE log4j2.appender.jdbc.c1.isEventTimestamp = true log4j2.appender.jdbc.c2.type = Column log4j2.appender.jdbc.c2.name = EVENT_LEVEL log4j2.appender.jdbc.c2.pattern = %level # setNString vs setString log4j2.appender.jdbc.c2.isUnicode = false log4j2.appender.jdbc.c3.type = Column log4j2.appender.jdbc.c3.name = EVENT_SOURCE log4j2.appender.jdbc.c3.pattern = %logger log4j2.appender.jdbc.c3.isUnicode = false log4j2.appender.jdbc.c4.type = Column log4j2.appender.jdbc.c4.name = EVENT_THREAD_ID log4j2.appender.jdbc.c4.pattern = %thread log4j2.appender.jdbc.c4.isUnicode = false log4j2.appender.jdbc.c5.type = Column log4j2.appender.jdbc.c5.name = EVENT_MESSAGE log4j2.appender.jdbc.c5.pattern = %message log4j2.appender.jdbc.c5.isUnicode = false
9. Test using this command:
karaf@root()> log:log "hey test 123"
10. Red Hat Fuse log you would get:
2019-01-04 19:26:46,098 | INFO | pipe-log:set INFO | o.a.k.l.core | 135 - org.apache.karaf.log.core - 4.2.0.fuse-720061-redhat-00001 | hey csp 123 2019-01-04 19:29:18,273 | INFO | g:log "hey test 123" | o.a.k.l.core | 135 - org.apache.karaf.log.core - 4.2.0.fuse-720061-redhat-00001 | hey test 123
11. In the database, execute select * from events;:
EVENT_ID EVENT_DATE EVENT_LEVEL EVENT_SOURCE EVENT_THREAD_ID EVENT_MESSAGE 199 2019-01-04 19:25:42 INFO org.apache.karaf.log.core pipe-log:set INFO hey csp 200 2019-01-04 19:26:08 INFO org.apache.karaf.log.core pipe-log:set INFO hey csp123 201 2019-01-04 19:26:46 INFO org.apache.karaf.log.core pipe-log:set INFO hey csp 123 202 2019-01-04 19:29:18 INFO org.apache.karaf.log.core pipe-log:log "hey test 123" hey test 123
That's it. I hope this article will not only help you configure a JDBC appender for persisting logs on Oracle Database 11g but also configure a datasource with Red Hat Fuse 7 in a Karaf environment. It should also help you gain some hands-on experience with Karaf commands.
