node-error-handler

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.

License

MIT