Confluent Schema Registry REST API cheatsheet
The Schema Registry support a REST API for finding out information about the schemas within it. Here’s a quick cheatsheat with REST calls that I often use.
HOWTO: Oracle GoldenGate + Apache Kafka + Schema Registry + Swingbench
This is the detailed step-by-step if you want to recreate the process I describe in the Confluent blog here
I used Oracle’s Oracle Developer Days VM, which comes preinstalled with Oracle 12cR2. You can see the notes on how to do this here. These notes take you through installing and configuring:
Swingbench, to create a sample “Order Entry” schema and simulate events on the Oracle database Oracle GoldenGate (OGG, forthwith) and Oracle GoldenGate for Big Data (OGG-BD, forthwith) I’m using Oracle GoldenGate 12.
Oracle GoldenGate / Kafka Connect Handler troubleshooting
The Replicat was kapput:
GGSCI (localhost.localdomain) 3> info rkconnoe REPLICAT RKCONNOE Last Started 2017-09-12 17:06 Status ABENDED Checkpoint Lag 00:00:00 (updated 00:46:34 ago) Log Read Checkpoint File /u01/app/ogg/dirdat/oe000000 First Record RBA 0 So checking the OGG error log ggserr.log showed
2017-09-12T17:06:17.572-0400 ERROR OGG-15051 Oracle GoldenGate Delivery, rkconnoe.prm: Java or JNI exception: oracle.goldengate.util.GGException: Error detected handling operation added event. 2017-09-12T17:06:17.572-0400 ERROR OGG-01668 Oracle GoldenGate Delivery, rkconnoe.prm: PROCESS ABENDING. So checking the replicat log dirrpt/RKCONNOE_info_log4j.
kafka-avro-console-producer - Error registering Avro schema / io.confluent.kafka.schemaregistry.client.rest.exceptions.RestClientException
By default, the kafka-avro-console-producer will assume that the schema registry is on port 8081, and happily connect to it. Unfortunately, this can lead to some weird errors if another process happens to be listening on port 8081 already!
[oracle@bigdatalite tmp]$ kafka-avro-console-producer \ > --broker-list localhost:9092 --topic kudu_test \ > --property value.schema='{"type":"record","name":"myrecord","fields":[{"name":"id","type":"int"},{"name":"random_field", "type": "string"}]}' {"id": 999, "random_field": "foo"} org.apache.kafka.common.errors.SerializationException: Error registering Avro schema: {"type":"record","name":"myrecord","fields":[{"name":"id","type":"int"},{"name":"random_field","type":"string"}]} Caused by: io.confluent.kafka.schemaregistry.client.rest.exceptions.RestClientException: Unexpected character ('<' (code 60)): expected a valid value (number, String, array, object, 'true', 'false' or 'null') at [Source: sun.
