Write - Influxdb — ContextQMD

Use the InfluxDB v2 JavaScript client library to write data from a Node.js environment to InfluxDB.

The JavaScript client library includes the following convenient features for writing data to InfluxDB:

Apply default tags to data points.
Buffer points into batches to optimize data transfer.
Automatically retry requests on failure.
Set an optional HTTP proxy address for your network.

Before you begin

Install the client library and other dependencies.

Write data with the client library

Instantiate a client by calling the new InfluxDB() constructor with your InfluxDB URL and database token (environment variables you already set in the Install section).

import {InfluxDB, Point} from '@influxdata/influxdb-client'

const influxDB = new InfluxDB({url: process.env.INFLUX_URL,
                               token: process.env.INFLUX_TOKEN})

Use the getWriteApi() method of the client to create a write client. Provide your InfluxDB organization ID and database name.

const writeApi = influxDB.getWriteApi(process.env.INFLUX_ORG,
                                       process.env.INFLUX_DATABASE)

To apply one or more tags to all points, use the useDefaultTags() method. Provide tags as an object of key/value pairs.
js
```
writeApi.useDefaultTags({region: 'west'})
```
Use the Point() constructor to create a point.
1. Call the constructor and provide a measurement.
2. To add one or more tags, chain the tag() method to the constructor. Provide a name and value.
3. To add a field of type float, chain the floatField() method to the constructor. Provide a name and value.
js
```
const point1 = new Point('temperature')
  .tag('sensor_id', 'TLM010')
  .floatField('value', 24.0)
```
Use the writePoint() method to write the point to your InfluxDB bucket. Finally, use the close() method to flush all pending writes. The example logs the new data point followed by "WRITE FINISHED" to stdout.
js
```
writeApi.writePoint(point1)

writeApi.close().then(() => {
  console.log('WRITE FINISHED')
})
```

Complete example

'use strict'
/** @module write
 * Writes a data point to InfluxDB using the JavaScript client library with Node.js.
**/

import {InfluxDB, Point} from '@influxdata/influxdb-client'

/**
 * Instantiate the InfluxDB client
 * with a configuration object.
 **/
const influxDB = new InfluxDB({url: process.env.INFLUX_URL,
                              token: process.env.INFLUX_TOKEN})

/**
 * Create a write client from the getWriteApi method.
 * Provide your org and database.
 **/
const writeApi = influxDB.getWriteApi(process.env.INFLUX_ORG,
                                      process.env.INFLUX_DATABASE)

/**
 * Apply default tags to all points.
 **/
writeApi.useDefaultTags({region: 'west'})

/**
 * Create a point and write it to the buffer.
 **/
const point1 = new Point('temperature')
  .tag('sensor_id', 'TLM01')
  .floatField('value', 24.0)
console.log(` ${point1}`)

writeApi.writePoint(point1)

/**
 * Flush pending writes and close writeApi.
 **/
writeApi.close().then(() => {
  console.log('WRITE FINISHED')
})

In your terminal with environment variables or env.js set, run the following command to execute the JavaScript file:

node write.js

Response codes

For information about InfluxDB API response codes, see InfluxDB API Write documentation.