OpenTSDB Line Protocol

Introduction

A single line of text is used in OpenTSDB line protocol to represent one row of data. OpenTSDB employs a single column data model, so each line can only contain a single data column. There can be multiple tags. Each line contains 4 parts as below:

<metric> <timestamp> <value> <tagk_1>=<tagv_1>[ <tagk_n>=<tagv_n>]

• metric will be used as the STable name.
• timestamp is the timestamp of current row of data. The time precision will be determined automatically based on the length of the timestamp. Second and millisecond time precision are supported.
• value is a metric which must be a numeric value, the corresponding column name is "value".
• The last part is the tag set separated by spaces, all tags will be converted to nchar type automatically.

For example:

meters.current 1648432611250 11.3 location=California.LoSangeles groupid=3

Please refer to OpenTSDB Telnet API for more details.

Examples

Java

package com.taos.example;

import com.taosdata.jdbc.SchemalessWriter;
import com.taosdata.jdbc.enums.SchemalessProtocolType;
import com.taosdata.jdbc.enums.SchemalessTimestampType;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;

public class TelnetLineProtocolExample {
    // format: <metric> <timestamp> <value> <tagk_1>=<tagv_1>[ <tagk_n>=<tagv_n>]
    private static String[] lines = { "meters.current 1648432611249 10.3 location=California.SanFrancisco groupid=2",
            "meters.current 1648432611250 12.6 location=California.SanFrancisco groupid=2",
            "meters.current 1648432611249 10.8 location=California.LosAngeles groupid=3",
            "meters.current 1648432611250 11.3 location=California.LosAngeles groupid=3",
            "meters.voltage 1648432611249 219 location=California.SanFrancisco groupid=2",
            "meters.voltage 1648432611250 218 location=California.SanFrancisco groupid=2",
            "meters.voltage 1648432611249 221 location=California.LosAngeles groupid=3",
            "meters.voltage 1648432611250 217 location=California.LosAngeles groupid=3",
    };

    private static Connection getConnection() throws SQLException {
        String jdbcUrl = "jdbc:TAOS://localhost:6030?user=root&password=taosdata";
        return DriverManager.getConnection(jdbcUrl);
    }

    private static void createDatabase(Connection conn) throws SQLException {
        try (Statement stmt = conn.createStatement()) {
            // the default precision is ms (microsecond), but we use us(microsecond) here.
            stmt.execute("CREATE DATABASE IF NOT EXISTS test precision 'us'");
            stmt.execute("USE test");
        }
    }

    public static void main(String[] args) throws SQLException {
        try (Connection conn = getConnection()) {
            createDatabase(conn);
            SchemalessWriter writer = new SchemalessWriter(conn);
            writer.write(lines, SchemalessProtocolType.TELNET, SchemalessTimestampType.NOT_CONFIGURED);
        }
    }

}

view source code

Python

import taos
from taos import SmlProtocol, SmlPrecision

# format: <metric> <timestamp> <value> <tagk_1>=<tagv_1>[ <tagk_n>=<tagv_n>]
lines = ["meters.current 1648432611249 10.3 location=California.SanFrancisco groupid=2",
         "meters.current 1648432611250 12.6 location=California.SanFrancisco groupid=2",
         "meters.current 1648432611249 10.8 location=California.LosAngeles groupid=3",
         "meters.current 1648432611250 11.3 location=California.LosAngeles groupid=3",
         "meters.voltage 1648432611249 219 location=California.SanFrancisco groupid=2",
         "meters.voltage 1648432611250 218 location=California.SanFrancisco groupid=2",
         "meters.voltage 1648432611249 221 location=California.LosAngeles groupid=3",
         "meters.voltage 1648432611250 217 location=California.LosAngeles groupid=3",
         ]


# create connection use firstEp in taos.cfg.
def get_connection():
    return taos.connect()


def create_database(conn):
    conn.execute("CREATE DATABASE test")
    conn.execute("USE test")


def insert_lines(conn):
    affected_rows = conn.schemaless_insert(
        lines, SmlProtocol.TELNET_PROTOCOL, SmlPrecision.NOT_CONFIGURED)
    print(affected_rows)  # 8


if __name__ == '__main__':
    connection = get_connection()
    try:
        create_database(connection)
        insert_lines(connection)
    finally:
        connection.close()

view source code

Go

package main

import (
	"fmt"

	"github.com/taosdata/driver-go/v2/af"
)

func prepareDatabase(conn *af.Connector) {
	_, err := conn.Exec("CREATE DATABASE test")
	if err != nil {
		panic(err)
	}
	_, err = conn.Exec("USE test")
	if err != nil {
		panic(err)
	}
}

func main() {
	conn, err := af.Open("localhost", "root", "taosdata", "", 6030)
	if err != nil {
		fmt.Println("fail to connect, err:", err)
	}
	defer conn.Close()
	prepareDatabase(conn)
	var lines = []string{
		"meters.current 1648432611249 10.3 location=California.SanFrancisco groupid=2",
		"meters.current 1648432611250 12.6 location=California.SanFrancisco groupid=2",
		"meters.current 1648432611249 10.8 location=California.LosAngeles groupid=3",
		"meters.current 1648432611250 11.3 location=California.LosAngeles groupid=3",
		"meters.voltage 1648432611249 219 location=California.SanFrancisco groupid=2",
		"meters.voltage 1648432611250 218 location=California.SanFrancisco groupid=2",
		"meters.voltage 1648432611249 221 location=California.LosAngeles groupid=3",
		"meters.voltage 1648432611250 217 location=California.LosAngeles groupid=3",
	}

	err = conn.OpenTSDBInsertTelnetLines(lines)
	if err != nil {
		fmt.Println("insert error:", err)
	}
}

view source code

Rust

use libtaos::schemaless::*;
use libtaos::*;

fn main() {
    let taos = TaosCfg::default().connect().expect("fail to connect");
    taos.raw_query("CREATE DATABASE test").unwrap();
    taos.raw_query("USE test").unwrap();
    let lines = [
        "meters.current 1648432611249 10.3 location=California.SanFrancisco groupid=2",
        "meters.current 1648432611250 12.6 location=California.SanFrancisco groupid=2",
        "meters.current 1648432611249 10.8 location=California.LosAngeles groupid=3",
        "meters.current 1648432611250 11.3 location=California.LosAngeles groupid=3",
        "meters.voltage 1648432611249 219 location=California.SanFrancisco groupid=2",
        "meters.voltage 1648432611250 218 location=California.SanFrancisco groupid=2",
        "meters.voltage 1648432611249 221 location=California.LosAngeles groupid=3",
        "meters.voltage 1648432611250 217 location=California.LosAngeles groupid=3",
    ];
    let affected_rows = taos
        .schemaless_insert(
            &lines,
            TSDB_SML_TELNET_PROTOCOL,
            TSDB_SML_TIMESTAMP_NOT_CONFIGURED,
        )
        .unwrap();
    println!("affected_rows={}", affected_rows); // affected_rows=8
}

// run with:  cargo run --example opentsdb_telnet_example

view source code

Node.js

const taos = require("td2.0-connector");

const conn = taos.connect({
  host: "localhost",
});

const cursor = conn.cursor();

function createDatabase() {
  cursor.execute("CREATE DATABASE test");
  cursor.execute("USE test");
}

function insertData() {
  const lines = [
    "meters.current 1648432611249 10.3 location=California.SanFrancisco groupid=2",
    "meters.current 1648432611250 12.6 location=California.SanFrancisco groupid=2",
    "meters.current 1648432611249 10.8 location=California.LosAngeles groupid=3",
    "meters.current 1648432611250 11.3 location=California.LosAngeles groupid=3",
    "meters.voltage 1648432611249 219 location=California.SanFrancisco groupid=2",
    "meters.voltage 1648432611250 218 location=California.SanFrancisco groupid=2",
    "meters.voltage 1648432611249 221 location=California.LosAngeles groupid=3",
    "meters.voltage 1648432611250 217 location=California.LosAngeles groupid=3",
  ];
  cursor.schemalessInsert(
    lines,
    taos.SCHEMALESS_PROTOCOL.TSDB_SML_TELNET_PROTOCOL,
    taos.SCHEMALESS_PRECISION.TSDB_SML_TIMESTAMP_NOT_CONFIGURED
  );
}

try {
  createDatabase();
  insertData();
} finally {
  cursor.close();
  conn.close();
}

view source code

C#

using TDengineDriver;

namespace TDengineExample
{
    internal class OptsTelnetExample
    {
        static void Main()
        {
            IntPtr conn = GetConnection();
            PrepareDatabase(conn);
            string[] lines = {
                "meters.current 1648432611249 10.3 location=California.SanFrancisco groupid=2",
                "meters.current 1648432611250 12.6 location=California.SanFrancisco groupid=2",
                "meters.current 1648432611249 10.8 location=California.LosAngeles groupid=3",
                "meters.current 1648432611250 11.3 location=California.LosAngeles groupid=3",
                "meters.voltage 1648432611249 219 location=California.SanFrancisco groupid=2",
                "meters.voltage 1648432611250 218 location=California.SanFrancisco groupid=2",
                "meters.voltage 1648432611249 221 location=California.LosAngeles groupid=3",
                "meters.voltage 1648432611250 217 location=California.LosAngeles groupid=3",
            };
            IntPtr res = TDengine.SchemalessInsert(conn, lines, lines.Length, (int)TDengineSchemalessProtocol.TSDB_SML_TELNET_PROTOCOL, (int)TDengineSchemalessPrecision.TSDB_SML_TIMESTAMP_NOT_CONFIGURED);
            if (TDengine.ErrorNo(res) != 0)
            {
                Console.WriteLine("SchemalessInsert failed since " + TDengine.Error(res));
                ExitProgram(conn, 1);
            }
            else
            {
                int affectedRows = TDengine.AffectRows(res);
                Console.WriteLine($"SchemalessInsert success, affected {affectedRows} rows");
            }
            TDengine.FreeResult(res);
            ExitProgram(conn, 0);

        }
        static IntPtr GetConnection()
        {
            string host = "localhost";
            short port = 6030;
            string username = "root";
            string password = "taosdata";
            string dbname = "";
            var conn = TDengine.Connect(host, username, password, dbname, port);
            if (conn == IntPtr.Zero)
            {
                Console.WriteLine("Connect to TDengine failed");
                TDengine.Cleanup();
                Environment.Exit(1);
            }
            else
            {
                Console.WriteLine("Connect to TDengine success");
            }
            return conn;
        }

        static void PrepareDatabase(IntPtr conn)
        {
            IntPtr res = TDengine.Query(conn, "CREATE DATABASE test");
            if (TDengine.ErrorNo(res) != 0)
            {
                Console.WriteLine("failed to create database, reason: " + TDengine.Error(res));
                ExitProgram(conn, 1);
            }
            res = TDengine.Query(conn, "USE test");
            if (TDengine.ErrorNo(res) != 0)
            {
                Console.WriteLine("failed to change database, reason: " + TDengine.Error(res));
                ExitProgram(conn, 1);
            }
        }

        static void ExitProgram(IntPtr conn, int exitCode)
        {
            TDengine.Close(conn);
            TDengine.Cleanup();
            Environment.Exit(exitCode);
        }
    }
}

view source code

C

int main() {
  TAOS *taos = taos_connect("localhost", "root", "taosdata", "", 6030);
  if (taos == NULL) {
    printf("failed to connect to server\n");
    exit(EXIT_FAILURE);
  }
  executeSQL(taos, "DROP DATABASE IF EXISTS test");
  executeSQL(taos, "CREATE DATABASE test");
  executeSQL(taos, "USE test");
  char *lines[] = {
      "meters.current 1648432611249 10.3 location=California.SanFrancisco groupid=2",
      "meters.current 1648432611250 12.6 location=California.SanFrancisco groupid=2",
      "meters.current 1648432611249 10.8 location=California.LosAngeles groupid=3",
      "meters.current 1648432611250 11.3 location=California.LosAngeles groupid=3",
      "meters.voltage 1648432611249 219 location=California.SanFrancisco groupid=2",
      "meters.voltage 1648432611250 218 location=California.SanFrancisco groupid=2",
      "meters.voltage 1648432611249 221 location=California.LosAngeles groupid=3",
      "meters.voltage 1648432611250 217 location=California.LosAngeles groupid=3",
  };
  TAOS_RES *res = taos_schemaless_insert(taos, lines, 8, TSDB_SML_TELNET_PROTOCOL, TSDB_SML_TIMESTAMP_NOT_CONFIGURED);
  if (taos_errno(res) != 0) {
    printf("failed to insert schema-less data, reason: %s\n", taos_errstr(res));
  } else {
    int affectedRow = taos_affected_rows(res);
    printf("successfully inserted %d rows\n", affectedRow);
  }

  taos_free_result(res);
  taos_close(taos);
  taos_cleanup();
}
// output:
// successfully inserted 8 rows

view source code

2 STables will be created automatically and each STable has 4 rows of data in the above sample code.

taos> use test;
Database changed.

taos> show STables;
              name              |      created_time       | columns |  tags  |   tables    |
============================================================================================
 meters.current                 | 2022-03-30 17:04:10.877 |       2 |      2 |           2 |
 meters.voltage                 | 2022-03-30 17:04:10.882 |       2 |      2 |           2 |
Query OK, 2 row(s) in set (0.002544s)

taos> select tbname, * from `meters.current`;
             tbname             |           ts            |           value           | groupid |            location            |
==================================================================================================================================
 t_0e7bcfa21a02331c06764f275... | 2022-03-28 09:56:51.249 |              10.800000000 | 3       | California.LoSangeles                |
 t_0e7bcfa21a02331c06764f275... | 2022-03-28 09:56:51.250 |              11.300000000 | 3       | California.LoSangeles                |
 t_7e7b26dd860280242c6492a16... | 2022-03-28 09:56:51.249 |              10.300000000 | 2       | California.SanFrancisco               |
 t_7e7b26dd860280242c6492a16... | 2022-03-28 09:56:51.250 |              12.600000000 | 2       | California.SanFrancisco               |
Query OK, 4 row(s) in set (0.005399s)