如何將數據發送到Node JS中的多個Kafka主題分區

Question

在Node js應用程序中，當我嘗試將消息發送到Kafka主題時，所有主題都將移至Partition0。該主題創建了4個分區，並且希望以循環機制進行發布，因此我嘗試了多個選項，但沒有運氣。

有什么辦法解決這個問題？ 下面是代碼片段。

payloads = [
    { topic: 'test-topic', messages: ['TestMessage1', 'TestMessage2', 'TestMessage3', 'TestMessage4']},
];
producer.on('ready', function(){
    producer.send(payloads, function(err, data){
        console.log("Successfully written onto Kafka");
    });

Answer 1

在Kafka中，具有相同密鑰的消息被放置在同一分區中。 您可以手動定義分區：

// Force partitioning - default partition is 0
payloads = [ 
    { topic: 'test-topic', messages: ['TestMessage1'], partition: 0 },
    { topic: 'test-topic', messages: ['TestMessage2'], partition: 1 },
    { topic: 'test-topic', messages: ['TestMessage3'], partition: 2 },
    { topic: 'test-topic', messages: ['TestMessage4'], partition: 3 }
];

或為每個消息使用不同的密鑰：

payloads = [ 
    { topic: 'test-topic', messages: ['TestMessage1'], key: '1' },
    { topic: 'test-topic', messages: ['TestMessage2'], key: '2' },
    { topic: 'test-topic', messages: ['TestMessage3'], key: '3' },
    { topic: 'test-topic', messages: ['TestMessage4'], key: '4' }
];

// Alternatively, you can use KeyedMessage
km = new KeyedMessage('1', 'TestMessage1'),
km2 = new KeyedMessage('2', 'TestMessage2'),
payloads = [
    { topic: 'test-topic', messages: [ km , km2 ] },
];