RudderStack Node.js SDK

The RudderStack Node.js SDK lets you track your customer event data from your Node.js applications and send it to your specified destinations.

Refer to the documentation for more details.

Installing the SDK

Run the following command to install the Node.js SDK via npm:

$ npm install @rudderstack/rudder-sdk-node

Using the SDK

To create a global RudderStack client object and use it for the subsequent event calls, run the following snippet:

const Analytics = require('@rudderstack/rudder-sdk-node');

const client = new Analytics(WRITE_KEY, {
  dataPlaneUrl: DATA_PLANE_URL, // default: https://hosted.rudderlabs.com
});

SDK Initialization Options

Below parameters are optional and can be passed during SDK initialization.

| Name | Type | Default value | Description | | :--------------------- | :------- | :------------------------------ | :------------------------------------------------------------------------------------------------ | | dataPlaneUrl | String | https://hosted.rudderlabs.com | The data plane URL. | | path | String | /v1/batch | Path to batch endpoint. | | flushAt | Number | 20 | The number of events to be flushed when reached this limit. | | flushInterval | Number | 10000 | The maximum timespan (in milliseconds) after which the events from the in-memory queue is flushed | | maxQueueSize | Number | 460800(500kb) | Maximum payload size of a batch request | | maxInternalQueueSize | Number | 20000 | The maximum length of the in-memory queue | | logLevel | String | 'info' | Log level. Ex: 'debug', 'error' | | axiosConfig | Object | N/A | Axios config | | axiosInstance | Object | N/A | Axios instance | | axiosRetryConfig | Object | N/A | Axios retry configuration | | retryCount | Number | 3 | Number of times requests will be retried by axios if failed | | errorHandler | Function | N/A | A function that will be called if request to server failed | | gzip | Boolean | true | Whether to compress request with gzip or not |

Supported calls

Refer to the SDK documentation for more information on the supported calls.

Initializing the SDK for data persistence

This is a beta feature. Contact us on our Community Slack in case you face any issues.

RudderStack has a data persistence feature to persist the events in Redis, leading to better event delivery guarantees. Also, the SDK can retry event delivery multiple times as the queue is maintained in a different process space(Redis).

| To use this feature, you will need to host a Redis server and use it as the intermediary data storage queue. | | :----------------------------------------------------------------------------------------------------------- |

A sample SDK initialization is shown below:

const client = new Analytics(
  "write_key",
  {
    dataPlaneUrl: DATA_PLANE_URL // default: https://hosted.rudderlabs.com with default path set to /v1/batch
    flushAt: <number> = 20,
    flushInterval: <ms> = 20000
    maxInternalQueueSize: <number> = 20000 // the max number of elements that the SDK can hold in memory,
                                                                // this is different than the Redis list created when persistence is enabled
  }
);
client.createPersistenceQueue({ redisOpts: { host: "localhost" } }, err => {})

To initialize the data persistence queue, you need to call the createPersistenceQueue method which takes two parameters as input - queueOpts and a callback. The createPersistenceQueue method will initialize a Redis list by calling Bull's utility methods.

If you do not call createPersistenceQueue after initializing the SDK, the SDK will not implement data persistence.

Read the detailed documentation for more information on createPersistenceQueue and the other configurable parameters.

Event flow

For more information on how the event flow occurs with data persistence enabled, refer to the documentation.

Limitations around data persistence

• Refer to this page to understand the limitations
• For more details on the limitations, read: https://redis.io/topics/cluster-tutorial#redis-cluster-data-sharding
• As a workaround, refer to this page: https://gitter.im/OptimalBits/bull/archives/2018/04/17. We pass a prefix with default value as {rudder}.

Contact us

If you come across any issues while configuring or using the RudderStack Node.js SDK, you can contact us or start a conversation in our Slack community.