homework-jianmu/docs/examples/node/nativeexample/subscribe_demo.js

52 lines
1.2 KiB
JavaScript

const taos = require("@tdengine/client");
const conn = taos.connect({ host: "localhost", database: "power" });
var cursor = conn.cursor();
function runConsumer() {
// create topic
cursor.execute("create topic topic_name_example as select * from meters");
let consumer = taos.consumer({
'group.id': 'tg2',
'td.connect.user': 'root',
'td.connect.pass': 'taosdata',
'msg.with.table.name': 'true',
'enable.auto.commit': 'true'
});
// subscribe the topic just created.
consumer.subscribe("topic_name_example");
// get subscribe topic list
let topicList = consumer.subscription();
console.log(topicList);
for (let i = 0; i < 5; i++) {
let msg = consumer.consume(100);
console.log(msg.topicPartition);
console.log(msg.block);
console.log(msg.fields)
consumer.commit(msg);
console.log(`=======consumer ${i} done`)
}
consumer.unsubscribe();
consumer.close();
// drop topic
cursor.execute("drop topic topic_name_example");
}
try {
runConsumer();
} finally {
setTimeout(() => {
cursor.close();
conn.close();
}, 2000);
}