docs-v2/content/shared/influxdb-client-libraries-r.../v2/javascript/nodejs/write.md

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Use the [InfluxDB v2 JavaScript client library](https://github.com/influxdata/influxdb-client-js) 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](/influxdb3/version/reference/client-libraries/v2/javascript/nodejs/install/).
### Write data with the client library
1. 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](/influxdb3/version/reference/client-libraries/v2/javascript/nodejs/install/)).
```js
import {InfluxDB, Point} from '@influxdata/influxdb-client'
const influxDB = new InfluxDB({url: process.env.INFLUX_URL,
token: process.env.INFLUX_TOKEN})
```
2. Use the `getWriteApi()` method of the client to create a **write client**.
Provide your InfluxDB organization ID and database name.
```js
const writeApi = influxDB.getWriteApi(process.env.INFLUX_ORG,
process.env.INFLUX_DATABASE)
```
3. To apply one or more [tags](/influxdb3/version/reference/glossary/#tag) to all points, use the `useDefaultTags()` method.
Provide tags as an object of key/value pairs.
```js
writeApi.useDefaultTags({region: 'west'})
```
4. Use the `Point()` constructor to create a [point](/influxdb3/version/reference/glossary/#point).
1. Call the constructor and provide a [measurement](/influxdb3/version/reference/glossary/#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)
```
5. 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
```js
'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](/influxdb3/version/reference/client-libraries/v2/javascript/nodejs/install/#configure-credentials), run the following command to execute the JavaScript file:
```sh
node write.js
```
### Response codes
_For information about **InfluxDB API response codes**, see
[InfluxDB API Write documentation](/influxdb3/version/api/#operation/PostWrite)._