Docs / Contact / sdks/javascript/configuration

JavaScript SDK: Configuration

All configuration is passed to the TendrlClient constructor. Only apiKey is required.

Constructor Options

Core

Option	Type	Default	Description
`apiKey`	string	—	Entity API key (required)
`apiBaseUrl`	string	`"https://app.tendrl.com/api"`	API base URL
`debug`	bool	`false`	Enable console debug logging

Batching & Performance

Option	Type	Default	Description
`minBatchSize`	number	`10`	Minimum messages per batch
`maxBatchSize`	number	`100`	Maximum messages per batch
`minBatchInterval`	number	`100`	Minimum ms between batch sends
`maxBatchInterval`	number	`1000`	Maximum ms before forced send
`maxQueueSize`	number	`1000`	Maximum messages in queue

Batch size adjusts dynamically based on queue load. When the queue is under 25% full, batches are sent quickly at minimum interval. When over 75% full, the SDK waits longer to build larger batches for efficiency.

Message Polling

Option	Type	Default	Description
`callback`	function	`null`	Catch-all when no `client.on()` route matches
`stateCallback`	function	`null`	Catch-all when no `client.onState()` handler is set
`checkMsgRate`	number	`3000`	Milliseconds between message polls
`checkMsgLimit`	number	`1`	Maximum messages per poll

Offline Storage

Option	Type	Default	Description
`offlineStorage`	bool	`false`	Enable IndexedDB persistence
`dbName`	string	`"tendrl_offline"`	IndexedDB database name

When enabled, messages that fail to send are stored in IndexedDB with a 1-hour TTL. They're automatically retried in batches of 50 when connectivity returns. Expired messages are cleaned up every 60 seconds.

Environment Variables

Variable	Used By	Description
`REACT_APP_TENDRL_KEY`	React hook	API key for `useTendrlClient`

React Hook Options

The useTendrlClient hook accepts the same options as the constructor, plus:

Option	Type	Default	Description
`onMessage`	function	`null`	Message callback (set as `callback`)

javascript


const { client, isConnected, publish } = useTendrlClient({
    apiKey: 'your_key',       // Or use REACT_APP_TENDRL_KEY env var
    onMessage: handleMessage,
    offlineStorage: true,
    checkMsgRate: 5000,
    debug: true
});

The hook automatically starts the client on mount and stops it on unmount.

Example Configurations

Development

javascript


const client = new TendrlClient({
    apiKey: 'dev_key',
    debug: true
});

Production Web App

javascript


const client = new TendrlClient({
    apiKey: process.env.REACT_APP_TENDRL_KEY,
    offlineStorage: true,
    maxBatchSize: 200,
    checkMsgRate: 5000,
    checkMsgLimit: 10
});

High-Frequency Node.js Service

javascript


const client = new TendrlClient({
    apiKey: process.env.TENDRL_KEY,
    minBatchSize: 50,
    maxBatchSize: 500,
    maxQueueSize: 5000,
    minBatchInterval: 50,
    maxBatchInterval: 500
});

Request Timeouts

The SDK uses these internal timeouts (not configurable):

Operation	Timeout
Single message send	5 seconds
Batch message send	30 seconds
Connection check	2 seconds

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