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Prerequisites

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Install SDK

To install the SDK, run the following: 
npm install @axiomhq/winston

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Import the Axiom transport for Winston

import { WinstonTransport as AxiomTransport } from '@axiomhq/winston';

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Create a Winston logger instance

const logger = winston.createLogger({
    level: 'info',
    format: winston.format.json(),
    defaultMeta: { service: 'user-service' },
    transports: [
        // You can pass an option here. If you don’t, the transport is configured automatically
        // using environment variables like `AXIOM_DATASET` and `AXIOM_TOKEN`
        new AxiomTransport({
            dataset: 'DATASET_NAME',
            token: 'API_TOKEN',
        }),
    ],
});
Replace API_TOKEN with the Axiom API token you have generated. For added security, store the API token in an environment variable.Replace DATASET_NAME with the name of the Axiom dataset where you send your data.
After setting up the Axiom transport for Winston, use the logger as usual: 
logger.log({
    level: 'info',
    message: 'Logger successfully setup',
});

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Error, exception, and rejection handling

To log errors, use the winston.format.errors formatter. For example: 
import winston from 'winston';
import { WinstonTransport as AxiomTransport } from '@axiomhq/winston';
const { combine, errors, stack } = winston.format;
const axiomTransport = new AxiomTransport({ ... });
const logger = winston.createLogger({
  // 8<----snip----
  format: combine(errors({ stack: true }), json()),
  // 8<----snip----
});
To automatically log exceptions and rejections, add the Axiom transport to the exceptionHandlers and rejectionHandlers. For example: 
import winston from 'winston';
import { WinstonTransport as AxiomTransport } from '@axiomhq/winston';
const axiomTransport = new AxiomTransport({ ... });
const logger = winston.createLogger({
  // 8<----snip----
  transports: [axiomTransport],
  exceptionHandlers: [axiomTransport],
  rejectionHandlers: [axiomTransport],
  // 8<----snip----
});
Running on Edge runtime isn’t supported.

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Examples

For more examples, see the examples in GitHub.