Express Request/Transaction Id Middleware

Description

Append transaction id to every request to the express server application. We can specify the existing id header or populate a new transaction id.

• TypeScript support.
• Populate id from existing header or generate a random uuid
• Setup a custom response header to pipe the transaction id to the requester
• Pass in any custom logic to generate a transaction id of your own

Quick Links

• Example Usage
• Custom Id Generator Usage Example
• API

Usage

Install

npm i @akrdevtech/lib-express-request-id

Example Usage

import * as express from 'express'
import { expressRequestId } from  '@akrdevtech/lib-express-request-id';

const app = express();

app.use(expressRequestId());

app.get('/', [
  (req, res) => { 
    res.send(`Hello World! ${req.txId}`) // Hello World! 44bd3872-f16c-46fc-a775-97d83c796432
  } 
]);

const port = 8000;
app.listen(port, () => {console.log(`⚡️ Service started : PORT → ${port}}`);

Custom Id Generator Usage Example

import * as express from 'express'
import { expressRequestId } from  '@akrdevtech/lib-express-request-id';

const app = express()

const customIdGen = (req: express.Request): string => {
	const id:string = // your random id generator logic here
	return id
}

app.use(expressRequestId({ customIdGenerator: customIdGen ));

app.get('/', [
  (req, res) => { 
    res.send(`Hello World! ${req.txId}`)
  } 
]);

const port = 8000;
app.listen(port, () => {console.log(`⚡️ Service started : PORT → ${port}}`);

API

expressRequestId(options?)

Options contains the following attributes

• requestHeaderName - Defines name of header, that should be used for checking and setting request ID.
  • Type: string
  • Default: "x-transaction-id"
• responseHeaderName - Defines name of header, that should be used for setting the id in reponse.
  • Type: string
  • Default: "x-transaction-id"
• setResponseHeader - Specifies whether the transaction id is to be set in the response header
  • Type: boolean
  • Default: true
• attributeName - Specifies the attribute name through which we can access the id from request object
  • Type: string
  • Default: 'txId'
• customIdGenerator - Defines a custom method that takes in optional attribute as request object and returns an id string
  • Type: Function
  • Interface: (request?: Express.Request)=>string
  • Default: (request?: Express.Request)=>string(UUID v4)