tdengine-client/examples/schemaless.js

A Node.js connector for TDengine.

const _ = require('lodash');
const taos = require('../tdengine');

var conn = taos.connect({ host: "127.0.0.1", user: "root", password: "taosdata", config: "/etc/taos", port: 10 });
var c1 = conn.cursor();
executeUpdate("drop database if exists  nodedb;");
executeUpdate("create database if not exists  nodedb ;");
executeUpdate("use nodedb;");

let tbName1 = "line_protocol_arr";
let tbName4 = "line_protocol_str";

let tbName2 = "json_protocol_arr";
let tbName3 = "json_protocol_str";



let line1 = [tbName1 + ",t1=3i64,t2=4f64,t3=\"t3\" c1=3i64,c3=L\"passit\",c2=false,c4=4f64 1626006833639000000",
tbName1 + ",t1=4i64,t3=\"t4\",t2=5f64,t4=5f64 c1=3i64,c3=L\"passitagin\",c2=true,c4=5f64,c5=5f64 1626006833641000000"
];
 
let line2 = ["{"
    + "\"metric\": \"" + tbName2 + "\","
    + "\"timestamp\": 1626006833,"
    + "\"value\": 10,"
    + "\"tags\": {"
    + " \"t1\": true,"
    + "\"t2\": false,"
    + "\"t3\": 10,"
    + "\"t4\": \"123_abc_.!@#$%^&*:;,./?|+-=()[]{}<>\""
    + "}"
    + "}"
];

let line3 = "{"
    + "\"metric\": \"" + tbName3 + "\","
    + "\"timestamp\": 1626006833000,"
    + "\"value\": 10,"
    + "\"tags\": {"
    + " \"t1\": true,"
    + "\"t2\": false,"
    + "\"t3\": 10,"
    + "\"t4\": \"123_abc_.!@#$%^&*:;,./?|+-=()[]{}<>\""
    + "}"
    + "}";

let line4 = tbName4 + ",t1=3i64,t2=4f64,t3=\"t3\" c1=3i64,c3=L\"passit\",c2=false,c4=4f64 1626006833639";

function executeUpdate(sql) {
    console.log(sql);
    c1.execute(sql);
}

function testSchemaless(tbName, numLines) {
    let sql = "select count(*) from " + tbName + ";";
    executeUpdate(sql);
    let affectRows = _.first(c1.fetchall());
    if (affectRows != numLines) {
        console.log(1);
        console.log(line2);
        throw "protocol " + tbName + " schemaless insert success,but can't select as expect."
    }
    else {
        console.log("protocol " + tbName + " schemaless insert success, can select as expect.")
    }
    console.log("===================")
}

function queryData(tbName) {
    let p = c1.query(`select * from ${tbName}`);
    p.execute().then((result) =>
        result.pretty()
    );
}



try {
    c1.schemalessInsert(line1, taos.SCHEMALESS_PROTOCOL.TSDB_SML_LINE_PROTOCOL, taos.SCHEMALESS_PRECISION.TSDB_SML_TIMESTAMP_NANO_SECONDS);
    queryData(tbName1);
    testSchemaless(tbName1, line1.length);

    c1.schemalessInsert(line2, taos.SCHEMALESS_PROTOCOL.TSDB_SML_JSON_PROTOCOL, taos.SCHEMALESS_PRECISION.TSDB_SML_TIMESTAMP_SECONDS);
    testSchemaless(tbName2, line2.length);
    queryData(tbName2);

    c1.schemalessInsert(line3, taos.SCHEMALESS_PROTOCOL.TSDB_SML_JSON_PROTOCOL, taos.SCHEMALESS_PRECISION.TSDB_SML_TIMESTAMP_MILLI_SECONDS);
    testSchemaless(tbName3, 1);
    queryData(tbName3);

    c1.schemalessInsert(line4, taos.SCHEMALESS_PROTOCOL.TSDB_SML_LINE_PROTOCOL, taos.SCHEMALESS_PRECISION.TSDB_SML_TIMESTAMP_MILLI_SECONDS);
    console.log(line4);
    testSchemaless(tbName4, 1);
    queryData(tbName4);
} catch (err) {
    console.log(err)
} finally {
    conn.close()
}