How to use Schema registry for Kafka Connect AVRO - apache-kafka

I have started exploring Kafka and Kafka connect recently and did some initial set up .
But wanted to explore more on schema registry part .
My schema registry is started now what i should do .
I have a AVRO schema stored in avro_schema.avsc.
here is the schema
{
"name": "FSP-AUDIT-EVENT",
"type": "record",
"namespace": "com.acme.avro",
"fields": [
{
"name": "ID",
"type": "string"
},
{
"name": "VERSION",
"type": "int"
},
{
"name": "ACTION_TYPE",
"type": "string"
},
{
"name": "EVENT_TYPE",
"type": "string"
},
{
"name": "CLIENT_ID",
"type": "string"
},
{
"name": "DETAILS",
"type": "string"
},
{
"name": "OBJECT_TYPE",
"type": "string"
},
{
"name": "UTC_DATE_TIME",
"type": "long"
},
{
"name": "POINT_IN_TIME_PRECISION",
"type": "string"
},
{
"name": "TIME_ZONE",
"type": "string"
},
{
"name": "TIMELINE_PRECISION",
"type": "string"
},
{
"name": "AUDIT_EVENT_TO_UTC_DT",
"type": [
"string",
"null"
]
},
{
"name": "AUDIT_EVENT_TO_DATE_PITP",
"type": "string"
},
{
"name": "AUDIT_EVENT_TO_DATE_TZ",
"type": "string"
},
{
"name": "AUDIT_EVENT_TO_DATE_TP",
"type": "string"
},
{
"name": "GROUP_ID",
"type": "string"
},
{
"name": "OBJECT_DISPLAY_NAME",
"type": "string"
},
{
"name": "OBJECT_ID",
"type": [
"string",
"null"
]
},
{
"name": "USER_DISPLAY_NAME",
"type": [
"string",
"null"
]
},
{
"name": "USER_ID",
"type": "string"
},
{
"name": "PARENT_EVENT_ID",
"type": [
"string",
"null"
]
},
{
"name": "NOTES",
"type": [
"string",
"null"
]
},
{
"name": "SUMMARY",
"type": [
"string",
"null"
]
}
]
}
Is my schema is valid .I converted it online from JSON ?
where should i keep this schema file location i am not sure about .
Please guide me with the step to follow
.
I am sending records from Lambda function and from JDBC source both .
So basically how can i enforce AVRO schema and test ?
Do i have to change anything in avro-consumer properties file ?
Or is this correct way to register schema
./bin/kafka-avro-console-producer \
--broker-list b-3.**:9092,b-**:9092,b-**:9092 --topic AVRO-AUDIT_EVENT \
--property value.schema='{"type":"record","name":"myrecord","fields":[{"name":"f1","type":"string"}]}'
curl -X POST -H "Content-Type: application/vnd.schemaregistry.v1+json" --data '{"schema" : "{\"type\":\"struct\",\"fields\":[{\"type\":\"string\",\"optional\":false,\"field\":\"ID\"},{\"type\":\"string\",\"optional\":true,\"field\":\"VERSION\"},{\"type\":\"string\",\"optional\":true,\"field\":\"ACTION_TYPE\"},{\"type\":\"string\",\"optional\":true,\"field\":\"EVENT_TYPE\"},{\"type\":\"string\",\"optional\":true,\"field\":\"CLIENT_ID\"},{\"type\":\"string\",\"optional\":true,\"field\":\"DETAILS\"},{\"type\":\"string\",\"optional\":true,\"field\":\"OBJECT_TYPE\"},{\"type\":\"string\",\"optional\":true,\"field\":\"UTC_DATE_TIME\"},{\"type\":\"string\",\"optional\":true,\"field\":\"POINT_IN_TIME_PRECISION\"},{\"type\":\"string\",\"optional\":true,\"field\":\"TIME_ZONE\"},{\"type\":\"string\",\"optional\":true,\"field\":\"TIMELINE_PRECISION\"},{\"type\":\"string\",\"optional\":true,\"field\":\"GROUP_ID\"},{\"type\":\"string\",\"optional\":true,\"field\":\"OBJECT_DISPLAY_NAME\"},{\"type\":\"string\",\"optional\":true,\"field\":\"OBJECT_ID\"},{\"type\":\"string\",\"optional\":true,\"field\":\"USER_DISPLAY_NAME\"},{\"type\":\"string\",\"optional\":true,\"field\":\"USER_ID\"},{\"type\":\"string\",\"optional\":true,\"field\":\"PARENT_EVENT_ID\"},{\"type\":\"string\",\"optional\":true,\"field\":\"NOTES\"},{\"type\":\"string\",\"optional\":true,\"field\":\"SUMMARY\"},{\"type\":\"string\",\"optional\":true,\"field\":\"AUDIT_EVENT_TO_UTC_DT\"},{\"type\":\"string\",\"optional\":true,\"field\":\"AUDIT_EVENT_TO_DATE_PITP\"},{\"type\":\"string\",\"optional\":true,\"field\":\"AUDIT_EVENT_TO_DATE_TZ\"},{\"type\":\"string\",\"optional\":true,\"field\":\"AUDIT_EVENT_TO_DATE_TP\"}],\"optional\":false,\"name\":\"test\"}"}' http://localhost:8081/subjects/view/versions
what next i have to do
But when i try to see my schema i get only below
curl --silent -X GET http://localhost:8081/subjects/AVRO-AUDIT-EVENT/versions/latest
this is the result
{"subject":"AVRO-AUDIT-EVENT","version":1,"id":161,"schema":"{\"type\":\"string\",\"optional\":false}"}
Why i do not see my full registered schema
Also when i try to delete schema
i get below error
{"error_code":405,"message":"HTTP 405 Method Not Allowed"
i am not sure if my schema is registered correctly .
Please help me.
Thanks in Advance

is my schema valid
You can use the REST API of the Registry to try and submit it and see...
where should i keep this schema file location i am not sure about
It's not clear how you're sending messages...
If you actually wrote Kafka producer code, you store it within your code (as a string) or as a resource file.. If using Java, you can instead use the SchemaBuilder class to create the Schema object
You need to rewrite your producer to use Avro Schema and Serializers if you've not already
If we create AVRO schema will it work for Json as well .
Avro is a Binary format, but there is a JSONDecoder for it.
what should be the URL for our AVRO schema properties file ?
It needs to be the IP of your Schema Registry once you figure out how to start it. (with schema-registry-start)
Do i have to change anything in avro-consumer properties file ?
You need to use the Avro Deserializer
is this correct way to register schema
.> /bin/kafka-avro-console-producer \
Not quite. That's how you produce a message with a schema (and you need to use the correct schema). You also must provide --property schema.registry.url
You use the REST API of the Registry to register and verify schemas

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JDBC sink topic with multiple structs to postgres

I am trying to sink a few topics top a postgres database. However the topic schema defines a array at the top level and within it multiple structs. Automapping does not work and I cannot find any reference how to handle this. I need all structs because they are dependent types, the second struct references the first struct as a field.
Currently it breaks when hitting the 2nd struct stating statusChangeEvent (struct) has no mapping to sql column type. This because it is using auto.create to make a table (probably called ProcessStatus) then when hitting the second entry there is no column of course.
[
{
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"fields": [
{
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{
"name": "name",
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{
"name": "description",
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{
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{
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}
]
},
{
"type": "record",
"name": "StatusChangeEvent",
"namespace": "company.some.process",
"fields": [
{
"name": "contNumber",
"type": "string"
},
{
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},
{
"name": "processVersion",
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{
"name": "extProcessId",
"type": [
"null",
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{
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{
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"type": "company.some.process.processStatus"
},
{
"name": "changeDateTime",
"type": "long",
"logicalType": "timestamp-millis"
},
{
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}
]
}
]
I am not using ksql atm. Which connector settings are suited for this task? If there is a ksql alternative it would be nice to know but the current requirement is to use the JDBC connector.
I tried using flatten but it does not support struct fields that have a schema. Which seems kind of weird. Aren't schema's the whole selling point of connect with kafka? Or is it more of a constraint you have to work around?
Aren't schema's the whole selling point of connect with kafka?
Yes, but Postgres (or the JDBC Sink, in general) doesn't really support nested objects within columns. For that, you're better off with a document database, such as using Mongo Sink Connector.
Which connector settings are suited for this task?
None, really, other than transforms. You could write your own if flatten doesn't work.
You could try pre-defining your table to use JSONB for the two status columns, however, that's more of a workaround.

What column type do I need for this nested data in BigQuery?

I have a JSON schema for a Kafka stream that I am integrating with BigQuery but I can't get the data type correct at the BigQuery end. This is the schema:
"my_meta_data": {
"type": "object",
"properties": {
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"items": {
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},
"property_2": {
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},
"property_3": {
"type": "array",
"items": {
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I tried this in the JSON file defining the BigQuery table:
{
"name": "my_meta_data",
"type": "RECORD",
"mode": "REPEATED",
"fields": [
{
"name": "property_1",
"type": "INT64",
"mode": "REPEATED"
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{
"name": "property_2",
"type": "INT64",
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},
{
"name": "property_3",
"type": "INT64",
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}
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I am using a hosted connector from Confluent, the Kafka provider, and the error message is
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I would like to convert my CSV dataflow to AVRO in NiFi 1.13.0 and send it to a Kafka topic with a Key and his Schema.
So I have multiple problems:
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Attach a custom Key with my message
I saw many things about processors that does not exist anymore so I would like to have a clear answer for the 1.13.0 NiFi version.
Here is my dataFlow :
Project,Price,Charges,hours spent,Days spent,price/day
API,75000,2500,1500,187.5,1000
Here is the AVRO Schema I'd like to have at the end :
{
"name": "projectClass",
"type": "record",
"fields": [
{
"name": "Project",
"type": "string"
},
{
"name": "Price",
"type": "int"
},
{
"name": "Charges",
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},
{
"name": "hours spent",
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},
{
"name": "Days spent",
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{
"name": "price/day",
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}
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I'm producing a message by using the kafka-avro-console-producer binary by doing:
kafka-avro-console-producer --broker-list broker:9092 --topic example-topic --property schema.registry.url='http://schema-registry:8081 --property value.schema='{"type": "record","name": "test","fields": [{"name": "before", "type": ["null", {"type": "record", "name": "columns", "fields":[{"name": "name", "type": "string"}]}],"default": "null"},{"name": "after", "type": ["null", "columns"],"default": "null"}]}'
{"before": null,"after": {"name": "John"}}'
sending the following message:
{"before": null,"after": {"name": "John"}}
and by appling the following Avro schema:
{
"type": "record",
"name": "test",
"fields": [{
"name": "before",
"type": ["null", {
"type": "record",
"name": "columns",
"fields": [{
"name": "name",
"type": "string"
}]
}],
"default": "null"
}, {
"name": "after",
"type": ["null", "columns"],
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}]
}
the error I'm getting in return is the following:
Caused by: org.apache.avro.AvroTypeException: Unknown union branch name
at org.apache.avro.io.JsonDecoder.readIndex(JsonDecoder.java:445)
at org.apache.avro.io.ResolvingDecoder.doAction(ResolvingDecoder.java:290)
at org.apache.avro.io.parsing.Parser.advance(Parser.java:88)
at org.apache.avro.io.ResolvingDecoder.readIndex(ResolvingDecoder.java:267)
at org.apache.avro.generic.GenericDatumReader.readWithoutConversion(GenericDatumReader.java:178)
at org.apache.avro.generic.GenericDatumReader.read(GenericDatumReader.java:152)
at org.apache.avro.generic.GenericDatumReader.readField(GenericDatumReader.java:240)
at org.apache.avro.generic.GenericDatumReader.readRecord(GenericDatumReader.java:230)
at org.apache.avro.generic.GenericDatumReader.readWithoutConversion(GenericDatumReader.java:174)
at org.apache.avro.generic.GenericDatumReader.read(GenericDatumReader.java:152)
at org.apache.avro.generic.GenericDatumReader.read(GenericDatumReader.java:144)
at io.confluent.kafka.formatter.AvroMessageReader.jsonToAvro(AvroMessageReader.java:213)
at io.confluent.kafka.formatter.AvroMessageReader.readMessage(AvroMessageReader.java:180)
at kafka.tools.ConsoleProducer$.main(ConsoleProducer.scala:55)
at kafka.tools.ConsoleProducer.main(ConsoleProducer.scala)
For those of you that are willing to go deeper into the rabbit hole, I'm making an integration between Oracle Golden Gate and Apache Kafka by using the Oracle Golden Gate Big Data connector. I'm currently experiencing problems with an equivalent model of the one described in here:
https://www.ateam-oracle.com/oracle-goldengate-big-data-adapter-apache-kafka-producer
When trying to apply the schema described in the above webpage to it's corresponding model(and after completing the JSON model), I'm getting the same error as the one I'm getting with the model and schema in the question.
Thank you all very much.
This is the problem
"type": ["null", "columns"]
You cannot refer back to other record types. You'll need to expand that out like you did for the other field

json schema issue on required property

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{
"id": "http://example.com/searchShops-schema#",
"$schema": "http://json-schema.org/draft-04/schema#",
"title": "searchShops Service",
"description": "",
"type": "object",
"properties": {
"city":{
"type": "string"
},
"address":{
"type": "string"
},
"zipCode":{
"type": "integer"
}
},
"required": ["city", "address", "zipCode"]
}
If your goal is to tell that "I want at least one member to exist" then use minProperties:
{
"type": "object",
"etc": "etc",
"minProperties": 1
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Note also that you can use "dependencies" to great effect if you also want additional constraints to exist when this or that member is present.
{
...
"anyOf": [
{ "required": ["city"] },
{ "required": ["address"] },
{ "required": ["zipcode"] },
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}
Or use "oneOf" if exactly one property should be present