--- title: Use compatibility APIs and client libraries to write data description: Use HTTP API endpoints compatible with InfluxDB v2 and v1 clients to write points as line protocol data to InfluxDB 3 Core. url: https://docs.influxdata.com/influxdb3/core/write-data/http-api/compatibility-apis/ estimated_tokens: 7686 product: InfluxDB 3 Core version: core --- # Use compatibility APIs and client libraries to write data Use compatibility APIs when you need to migrate existing InfluxDB v1 or v2 write workloads to InfluxDB 3.x. The `/api/v2/write` (v2-compatible) and `/write` (v1-compatible) HTTP API endpoints work with InfluxDB [client libraries](/influxdb3/core/reference/client-libraries/), [Telegraf](/telegraf/v1/), and third-party integrations to write points as line protocol data to InfluxDB 3 Core. #### Choose the write endpoint for your workload When creating new write workloads, use the [InfluxDB HTTP API `/api/v3/write_lp` endpoint](/influxdb3/core/write-data/http-api/v3-write-lp/) and [client libraries](/influxdb3/core/write-data/client-libraries/). When bringing existing v1 write workloads, use the [v1-compatible `/write` endpoint](#influxdb-v1-compatibility). When bringing existing v2 write workloads, use the [v2-compatible `/api/v2/write` endpoint](#influxdb-v2-compatibility). **For Telegraf**, use the InfluxDB v1.x [`outputs.influxdb`](/telegraf/v1/output-plugins/influxdb/) or v2.x [`outputs.influxdb_v2`](/telegraf/v1/output-plugins/influxdb_v2/) output plugins. See how to [use Telegraf to write data](/influxdb3/core/write-data/use-telegraf/). #### Compatibility APIs differ from native APIs Keep in mind that the compatibility APIs differ from the v1 and v2 APIs in previous versions in the following ways: - Tags in a table (measurement) are *immutable* - A tag and a field can’t have the same name within a table. ## InfluxDB v2 compatibility The `/api/v2/write` InfluxDB v2 compatibility endpoint provides backwards compatibility with clients that can write data to InfluxDB OSS v2.x and Cloud 2 (TSM). [POST /api/v2/write?bucket=mydb&precision=ns](/influxdb3/core/api/write-data/) ### Authenticate v2 API requests InfluxDB 3 Core requires each API request to be authenticated with a [token](/influxdb3/core/admin/tokens/) . Use the `Authorization: Bearer` or `Authorization: Token` scheme to authenticate v2 API write requests: #### Syntax ```http Authorization: Bearer DATABASE_TOKEN ``` ```http Authorization: Token DATABASE_TOKEN ``` #### Examples Use `Bearer` to authenticate a v2 write request: ```sh curl -i "https://localhost:8181/api/v2/write?bucket=DATABASE_NAME&precision=s" \ --header "Authorization: Bearer DATABASE_TOKEN" \ --header "Content-type: text/plain; charset=utf-8" \ --data-binary 'home,room=kitchen temp=72 1641024000' ``` Use `Token` to authenticate a v2 write request: ```sh curl -i "https://localhost:8181/api/v2/write?bucket=DATABASE_NAME&precision=s" \ --header "Authorization: Token DATABASE_TOKEN" \ --header "Content-type: text/plain; charset=utf-8" \ --data-binary 'home,room=kitchen temp=72 1641024000' ``` ### v2 API write parameters For InfluxDB 3 Core v2 API `/api/v2/write` requests, set parameters as listed in the following table: | Parameter | Allowed in | Ignored | Value | | --- | --- | --- | --- | | bucket * | Query string | Honored | Database name | | precision | Query string | Honored | Timestamp precision | | Content-Encoding | Header | Honored | gzip (compressed data) or identity (uncompressed) | | Authorization | Header | Honored | Bearer DATABASE_TOKEN or Token DATABASE_TOKEN | \* = Required #### Timestamp precision By default, InfluxDB 3 Core uses the timestamp magnitude to auto-detect the precision. To avoid any ambiguity, you can specify the precision of timestamps in your data. Use one of the following `precision` values in v2 API `/api/v2/write` requests: - `ns`: nanoseconds - `us`: microseconds - `ms`: milliseconds - `s`: seconds - `m`: minutes - `h`: hours ## InfluxDB v1 compatibility The `/write` InfluxDB v1 compatibility endpoint provides backwards compatibility with clients that can write data to InfluxDB v1.x. [POST /write?db=mydb&precision=ns](/influxdb3/core/api/write-data/) ### Authenticate v1 API requests InfluxDB 3 Core requires each API request to be authenticated with a [token](/influxdb3/core/admin/tokens/) . With InfluxDB v1-compatible endpoints in InfluxDB 3, you can use database tokens in InfluxDB 1.x username and password schemes, in the InfluxDB v2 `Authorization: Token` scheme, or in the OAuth `Authorization: Bearer` scheme. - [Authenticate with a username and password scheme](#authenticate-with-a-username-and-password-scheme) - [Authenticate with a token scheme](#authenticate-with-a-token-scheme) #### Authenticate with a username and password scheme With InfluxDB v1-compatible endpoints, you can use the InfluxDB 1.x convention of username and password to authenticate database writes by passing a [token](/influxdb3/core/admin/tokens/) as the `password` credential. When authenticating requests to the v1 API `/write` endpoint, InfluxDB 3 Core checks that the `password` (`p`) value is an authorized [token](/influxdb3/core/admin/tokens/) . InfluxDB 3 Core ignores the `username` (`u`) parameter in the request. Use one of the following authentication schemes with clients that support Basic authentication or query parameters: - [Basic authentication](#basic-authentication-v1) - [Query string authentication](#query-string-authentication-v1) ##### Basic authentication Use the `Authorization` header with the `Basic` scheme to authenticate v1 API `/write` requests. When authenticating requests, InfluxDB 3 Core checks that the `password` part of the decoded credential is an authorized [token](/influxdb3/core/admin/tokens/) . InfluxDB 3 Core ignores the `username` part of the decoded credential. ###### Syntax ```http Authorization: Basic ``` Encode the `[USERNAME]:DATABASE_TOKEN` credential using base64 encoding, and then append the encoded string to the `Authorization: Basic` header. ###### Example The following example shows how to use cURL with the `Basic` authentication scheme: ```sh curl -i "https://localhost:8181/write?db=DATABASE_NAME&precision=s" \ --user "any:DATABASE_TOKEN" \ --header "Content-type: text/plain; charset=utf-8" \ --data-binary 'home,room=kitchen temp=72 1641024000' ``` ##### Query string authentication In the URL, pass the `p` query parameter to authenticate `/write` requests. When authenticating requests, InfluxDB 3 Core checks that the `p` (*password*) value is an authorized [token](/influxdb3/core/admin/tokens/) and ignores the `u` (*username*) parameter. ###### Syntax ```sh https://localhost:8181/write/?u=any&p=DATABASE_TOKEN ``` ###### Example The following example shows how to use cURL with query string authentication: ```sh curl -i "https://localhost:8181/write?db=DATABASE_NAME&precision=s&p=DATABASE_TOKEN" \ --header "Content-type: text/plain; charset=utf-8" \ --data-binary 'home,room=kitchen temp=72 1641024000' ``` #### Authenticate with a token scheme Use the `Authorization: Bearer` or the `Authorization: Token` scheme to pass a [token](/influxdb3/core/admin/tokens/) for authenticating v1 API `/write` requests. `Bearer` and `Token` are equivalent in InfluxDB 3 Core. The `Token` scheme is used in the InfluxDB 2.x API. `Bearer` is defined by the [OAuth 2.0 Framework](https://www.rfc-editor.org/rfc/rfc6750#page-14). Support for one or the other may vary across InfluxDB API clients. ##### Syntax ```http Authorization: Bearer DATABASE_TOKEN ``` ```http Authorization: Token DATABASE_TOKEN ``` ##### Examples Use `Bearer` to authenticate a v1 write request: ```sh curl -i "https://localhost:8181/write?db=DATABASE_NAME&precision=s" \ --header "Authorization: Bearer DATABASE_TOKEN" \ --header "Content-type: text/plain; charset=utf-8" \ --data-binary 'home,room=kitchen temp=72 1641024000' ``` Use `Token` to authenticate a v1 write request: ```sh curl -i "https://localhost:8181/write?db=DATABASE_NAME&precision=s" \ --header "Authorization: Token DATABASE_TOKEN" \ --header "Content-type: text/plain; charset=utf-8" \ --data-binary 'home,room=kitchen temp=72 1641024000' ``` ### v1 API write parameters For InfluxDB 3 Core v1 API `/write` requests, set parameters as listed in the following table: | Parameter | Allowed in | Ignored | Value | | --- | --- | --- | --- | | consistency | Query string | Ignored | N/A | | db * | Query string | Honored | Database name | | precision | Query string | Honored | Timestamp precision | | rp | Query string | Honored, but discouraged | Retention policy | | u | Query string | Ignored | For query string authentication, any arbitrary string | | p | Query string | Honored | For query string authentication, a token | `Content-Encoding` | Header | Honored | `gzip` (compressed data) or `identity` (uncompressed) `Authorization` | Header | Honored | `Bearer DATABASE_TOKEN`, `Token DATABASE_TOKEN`, or `Basic ` \* = Required #### Timestamp precision By default, InfluxDB 3 Core uses the timestamp magnitude to auto-detect the precision. To avoid any ambiguity, you can specify the precision of timestamps in your data. Use one of the following `precision` values in v1 API `/write` requests: - `ns`: nanoseconds - `us`: microseconds - `ms`: milliseconds - `s`: seconds - `m`: minutes - `h`: hours ## Client library examples Use language-specific client libraries with your custom code to write data to InfluxDB 3 Core. ### v1 client libraries v1 client libraries send data in [line protocol](/influxdb3/core/reference/syntax/line-protocol/) syntax to the v1 API `/write` endpoint. **Node.js:** Create a v1 API client using the [node-influx](/influxdb/v1/tools/api_client_libraries/#javascriptnodejs) JavaScript client library: ```js const Influx = require('influx') // Instantiate a client for writing to InfluxDB 3 Core v1 API const client = new Influx.InfluxDB({ host: 'localhost:8181', port: 443, protocol: 'https', database: 'DATABASE_NAME', username: 'ignored', password: 'DATABASE_TOKEN' }) ``` **Python:** Create a v1 API client using the [influxdb-python](/influxdb/v1/tools/api_client_libraries/#python) Python client library: ```py from influxdb import InfluxDBClient # Instantiate a client for writing to InfluxDB 3 Core v1 API client = InfluxDBClient( host='localhost:8181', ssl=True, database='DATABASE_NAME', username='', password='DATABASE_TOKEN', headers={'Content-Type': 'text/plain; charset=utf-8'} ) ``` ### v2 client libraries v2 client libraries send data in [line protocol](/influxdb3/core/reference/syntax/line-protocol/) syntax to the v2 API `/api/v2/write` endpoint. For more information about using v2 client libraries, see [v2 client libraries](/influxdb3/core/reference/client-libraries/v2/). ## Telegraf configuration If you have existing v1 workloads that use Telegraf, you can use the [InfluxDB v1.x `influxdb` Telegraf output plugin](/telegraf/v1/output-plugins/influxdb/) to write data. The following table shows `outputs.influxdb` plugin parameters and values for writing to the InfluxDB 3 Core v1 API: | Parameter | Ignored | Value | | --- | --- | --- | | database | Honored | Database name | | retention_policy | Honored, but discouraged | Duration | | username | Ignored | String or empty | | password | Honored | token | `content_encoding` | Honored | `gzip` (compressed data) or `identity` (uncompressed) `skip_database_creation` | Ignored | N/A (see how to [create a database](/influxdb3/core/admin/databases/create/)) To configure the v1.x output plugin for writing to InfluxDB 3 Core, add the following `outputs.influxdb` configuration in your `telegraf.conf` file: ```toml [[outputs.influxdb]] urls = ["https://localhost:8181"] database = "DATABASE_NAME" skip_database_creation = true retention_policy = "" username = "ignored" password = "DATABASE_TOKEN" content_encoding = "gzip" ``` Replace the following configuration values: - `DATABASE_NAME`: the name of the [database](/influxdb3/core/admin/databases/) to write to - `DATABASE_TOKEN`: your InfluxDB 3 Core [token](/influxdb3/core/admin/tokens/) #### Related - [Write data to InfluxDB 3 Core](/influxdb3/core/get-started/write/) - [InfluxDB v2 API client libraries](/influxdb3/core/reference/client-libraries/v2/) - [/api/v2/write (v2-compatible) endpoint](/influxdb3/core/api/write-data/#operation/PostV2Write) - [/write (v1-compatible) endpoint](/influxdb3/core/api/write-data/#operation/PostV1Write)