On application start-up: "TypeError: Cannot set property 'expose' of undefined"

[tamitutor]

My code for requiring expose looks like this:

------------------BEGIN CODE---------------------
var express = require('express')
, expose = require('express-expose')
, program = require('commander')
, cookie = require('cookie')
, routes = require('./routes')
, api = require('./routes/api.js')
, passport = require('passport')
, BasicStrategy = require('passport-http').BasicStrategy
, config = require('config')
;

program
.version('0.0.1')
.option('-t, --test', 'Run as a test')
.parse(process.argv);

var app = module.exports = express.createServer();
------------------END CODE---------------------

The specific line in express-expose.js throwing the error is line 44.

Please see the attached image...

[jonpacker]

It looks like you might be using an old version of express that doesn't expose the express app prototype that way that express-expose expects. If you upgrade to express 3 this should fix itself.

[lbeschastny]

According to express-expose Readme.md, latest express-expose@0.3.4 is only compatible with express@4.x:

• express@4.x (use express-expose at >= 0.3.4)
• express@3.x (use express-expose at >= 0.2.3 and <= 0.3.3)
• express@2.x (use express-expose at <= 0.2.2)

Using the same patch version for different major releases of express seems like a violation of Semantic Versioning to me.

[niftylettuce]

@lbeschastny pull request welcome

[lbeschastny]

@niftylettuce I don't think that anything could be done about express@2.x/express@3.x.

As for express@3.x/express@4.x, you could re-release latest express-expose under 0.4.0 version, marking current express-expose@0.3.4 release as deprecated (or even unpublishing it). It'll resolve all versioning problems for express@3.x users.

As for pull-request, maintiners usually don't like contributors messing with package version, but if you want, I'll create one. Though, it'll be pointless without either deprecating or unpublishing current express-expose@0.3.4 release.