express-error-logging-middleware

npm package for express error logging middleware, storing errors in server and pin-pointing the troubled api.

1. It is a middleware, compatible with express framework, needs to be placed as middleware in route function after the controller call.
2. Stores all 4XX and 5XX errors on server that are passed as next(err) or next(new Error()) way.
3. And helps into troubleshooting apis by finding which api has logged most errors.

How to pass as middleware?

const { errorLoggingMiddleware } = require("express-error-logging-middleware");
 getRoutes(){
     this.route.get("/get", (req, res, next) => {
      this.controller.someController(req, res, next)
    },errorLoggingMiddleware);
  }

It creates two .txt files, (err-400.txt and err-500.txt) in root directory, to store 4XX and 5XX errors respectively.

How to pass err in next()

next(error);

or

next(new Error("err"))

• error can be array or string

Functions

1

getLatestErrors(statusType, countFromLast)

statusType can be 4XX or 5XX countFromLast is an integer.

eg. getLatestErrors(404, 10); Will return the list of lastest 10 errors of statusCode 4XX, that has occured in the application.

2

getApiWithMostError(statusType)

statusType can be 4XX or 5XX

eg. getApiWithMostError(500); Will return the api name and its error count of type 5XX. For example ['v1/api/get', 20] means, 'v1/api/get' api encountered 5XX error the highest number of times compared to any other api, and the count is 20.