TypeError: Cannot read properties of undefined (reading 'app')

[pddec]

I'm getting this error below when I send a request to my server. I don't have any idea what causes that error. Would someone be able to help me?

[shahardra]

/opt/hostedtoolcache/node/16.20.2/x64/bin/npm --version

[joeyguerra]

It's hard for me to tell without seeing the rest of the code. But var app = this.app; is suspicious to me. Can you change that code to not use the this keyword? instead, just reference app?

The error message implies that the this context is not set when the response.js code tries to use it's internal reference to the express app, app.

[krzysdz]

var app = this.app; is code inside Express that the stack trace is pointing to:

express/lib/response.js

Lines 266 to 271 in 2a00da2

	// settings
	var app = this.app;
	var escape = app.get('json escape')
	var replacer = app.get('json replacer');
	var spaces = app.get('json spaces');
	var body = stringify(val, replacer, spaces, escape)