@flarelog/sdk

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@flarelog/sdk / withVercelServerless

Function: withVercelServerless()

withVercelServerless(logger, handler): VercelServerlessHandler

Defined in: frameworks/vercel.ts:89

Wrap a Vercel Serverless Function handler with automatic logging and tracing.

What it does:

• Extracts or generates a traceId from incoming request headers
• Creates a child logger with request context (method, path, traceId)
• Attaches the child logger and traceId to req for downstream use
• Logs request completion with duration and status code
• Captures and logs unhandled errors before re-throwing
• Uses res.on("finish") to reliably capture the final status code

Parameters

logger

FlareLog

handler

VercelServerlessHandler

Returns

VercelServerlessHandler

Examples

Basic usage

// api/hello.ts
import { flarelog } from "@flarelog/sdk";
import { withVercelServerless } from "@flarelog/sdk/vercel";

const logger = flarelog({});

export default withVercelServerless(logger, async (req, res) => {
  req.logger.info("Processing request");
  res.json({ message: "Hello from Vercel!" });
});

With Flarelog API key

// Set FLARELOG_API_KEY in Vercel project environment variables
const logger = flarelog({});
// → ships logs to your flarelog.dev dashboard