Node-error-handler NPM

node-error-handler

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Installation

npm install node-error-handler --save

Usage

In an express based application:

const  express = require('express');
const  error_handler = require('node-error-handler');
  
const  app = express();

// Handling GET request to '/foo' endpoint
app.get('/foo', (req, res, next) => {
  // Creating a new Error object with a custom message
  const  error = new  Error('Missing field: `name`');
  // Setting a custom error code
  error.code = 422;
  
  // Passing the error to the next middleware function
  next(error);
});

// Adding error handling middleware
app.use(error_handler({ 
  debug: true, // Enable debug mode
  trace: app.get('env') === 'development', // Enable trace if environment is set to development
  camel_case: true // Convert error keys to camel case
  }));

Options

Option	Type	Default	Description
debug	Boolean	`false`	If `true` all errors are printed with stderr.
trace	Boolean	`false`	If `true` the trace is attached to output. (Recommended use in development only)
camel_case	Boolean	`false`	If `true` The camelCase approach is used by error handler.

Example

5xx error camel_case: false:

{ "error": { "status_code": 500,"code": "INTERNAL_SERVER_ERROR" } }

5xx error camel_case: true:

{ "error": { "statusCode": 500,"code": "INTERNAL_SERVER_ERROR" } }

5xx error trace: false:

{ "error": { "status_code": 500,"code": "INTERNAL_SERVER_ERROR" } }

5xx error with transaction_id:

{ "error": { "status_code": 500,"code": "INTERNAL_SERVER_ERROR", "transaction_id": "7616e2d3-6b90-43ba-8548-f6en12384f39" } }

5xx error trace: true:

{ "error": 
  { "status_code": 500,
    "code": "INTERNAL_SERVER_ERROR",
    "trace":   
    at Module._compile (internal/modules/cjs/loader.js:892:18)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:973:10)
    at Module.load (internal/modules/cjs/loader.js:812:32)
    at Function.Module._load (internal/modules/cjs/loader.js:724:14)
    at Function.Module.runMain (internal/modules/cjs/loader.js:1025:10)
    at internal/main/run_main_module.js:17:11 
    } 
}

The error object could contain the following fields:

Error Key	Purpose
status_code	HTTP status code for response. Default value: `500` (Internal Server Error).
message	Error message.
code	Error code, associated with `status_code`.
trace	Trace including data for dubug such as file, paths.
transaction_id	Unique identifier value that is attached to requests and messages that allow reference to a particular transaction or event chain.