kafka-avro-stub

Stubs for the kafka-avro library.

Install

Install the module using NPM:

npm install kafka-avro-stub --save-dev

Documentation

Quick Usage

var KafkaAvro = require('kafka-avro');
var KafkaAvroStub = require('kafka-avro-stub');
var schemaRegistryFix = require('./fixtures/schema-registry.fix');

// Instantiate Kafka Avro
var kafkaAvro = new KafkaAvro(kafkaConf);

// Instantiate the Kafka Avro Stub
var kafkaAvroStub = new KafkaAvroStub(kafkaAvro);

// Before you invoke the kafkaAvro.init() method stub:
kafkaAvroStub.stub(schemaRegistryFix);

/* ... */

// Reset
kafkaAvroStub.reset();

How does it work

The Kafka Avro Stub will provide complete mock objects of the Consumer and Produce node-rdkafka Constructors. It will also stub the behavior of the kafkaAvro.init() method.

kafka-avro-stub mocks behaviors of:

• Producer.produce() Typical method of producing.
• Consumer.on('data') Using the consume() and data event.
• Consumer.getReadStream() Using readable streams.

It will properly consume and produce messages, acting like a Kafka server. The messages produced are proper Kafka produced messages with all the expected keys:

• topic Topic name.
• value Raw value in byte code.
• parsed Deserialized object (as passed).
• offset Message offset.
• size Size of the message.
• partition Partition used.
• key Key used.

kafkaAvroStub.stub(schemaRegistryFix)

You only need to invoke the stub() method once per runtime, not in every test. If you run stub() again, it will simply invoke the reset() method. The argument required is a fixture representing the response of the Schema Registry.

schemaRegistryFix is an Array of Objects which must have the following properties:

• subject {string} The full topic name. Do not include -value or -key suffixes.
• version {number} The version number of the schema, use 1.
• id {number} The schema id, any unique number will do.
• schema {string} JSON serialized schema. Stringify your Avro schema objects or .avsc files.

kafkaAvroStub.reset()

Run this method between your tests to reset all listeners and counters.

Available Properties

Kafka avro stub provides the following properties after the stub() method is invoked:

• kafkaAvroStub.kafkaAvroInitsStub {sinon.Stub} Sinon stub of the kafkaAvro.init() method.
• kafkaAvroStub.produceSpies {Array.<sinon.Spy>} Sinon spy on the Producer.produce() method, will be stored in the order they were invoked.
• kafkaAvroStub.consumeCommitSpies {Array.<sinon.Spy>} Sinon spy on the Consumer.commit() method, will be stored in the order they were invoked.
• kafkaAvroStub.messagesProduced {Object.} An object with topic names as keys and values an Array of messages produced on that topic in sequence.

All of the above properties are reset when the reset() method is invoked.

WARNING The kafkaAvroStub.produceSpies and kafkaAvroStub.consumeCommitSpies Arrays will not be emptied with the reset() method, however the Sinon Spies they contain will get reset.

Known Limitations

• There are no receipts emitted through the delivery-report event.
• There are no events emitted other than data.
• If multiple consumers are instantiated they will all be treated as one. Do not expect topic separation between them, you shouldn't have more than one Consumers per runtime anyway.
• There is no manual committing, all messages is assumed are committed as they are received.
• Once you go stub you never go back.

If you need any of the above limitations lifted first step is to open an Issue and a second step, if you want to achieve awesomeness, would be to submit a pull request.

Version Support Table

| kafka-avro-stub | kafka-avro | |---------------------|---------------| | From 0.3.0 | From 0.7.0| | Up to 0.2.1 | Up to 0.6.4|

Releasing

1. Update the changelog bellow.
2. Ensure you are on master.
3. Type: grunt release
   • grunt release:minor for minor number jump.
   • grunt release:major for major number jump.

Release History

• v0.3.0, 03 Mar 2017
  • Support kafka-avro ^0.7.0.
• v0.2.1, 16 Feb 2017
  • Support connect() and ready event which have been decoupled from ^0.6.0.
• v0.2.0, 15 Feb 2017
  • Added subscribe stub on Consumers, use kafka-avro 0.5.0.
• v0.1.0, 02 Feb 2017
  • Created two new arrays kafkaAvroStub.produceSpies and kafkaAvroStub.consumeCommitSpies, the first one replaced the kafkaAvroStub.produceSpy.
• v0.0.3, 02 Feb 2017
  • Created and exposed a spy on the producer.produce() method.
• v0.0.2, 02 Feb 2017
  • reset() method will not reset the registered consumers.
• v0.0.1, 01 Feb 2017
  • Big Bang.

License

Copyright Waldo, Inc. Licensed under the MIT.