Express js Route.get() requires a callback function but got a [object Undefined]

Attempting to learn Expresss.js via this tutorial and I am at the point of adding routes. I believe I have followed the tutorial exactly, but I am getting this error:

[nodemon] starting `node ./bin/www`

/Users/dariusgoore/development/express-locallibrary-tutorial/node_modules/express/lib/router/route.js:202

    throw new Error(msg);

    ^



Error: Route.get() requires a callback function but got a [object  Undefined]

    at Route.(anonymous function) [as get] (/Users/dariusgoore/development/express-locallibrary-tutorial/node_modules/express/lib/router/route.js:202:15)

    at Function.proto.(anonymous function) [as get] (/Users/dariusgoore/development/express-locallibrary-tutorial/node_modules/express/lib/router/index.js:510:19)

    at Object.<anonymous> (/Users/dariusgoore/development/express-locallibrary-tutorial/routes/catalog.js:86:8)

    at Module._compile (internal/modules/cjs/loader.js:689:30)

    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)

    at Module.load (internal/modules/cjs/loader.js:599:32)

    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)

    at Function.Module._load (internal/modules/cjs/loader.js:530:3)

    at Module.require (internal/modules/cjs/loader.js:637:17)

    at require (internal/modules/cjs/helpers.js:22:18)

    at Object.<anonymous> (/Users/dariusgoore/development/express-locallibrary-tutorial/app.js:9:21)

    at Module._compile (internal/modules/cjs/loader.js:689:30)

    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)

    at Module.load (internal/modules/cjs/loader.js:599:32)

    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)

    at Function.Module._load (internal/modules/cjs/loader.js:530:3)

[nodemon] app crashed - waiting for file changes before starting...

Here are the relevant files:

routes/catalog.js

var express = require('express');

var router = express.Router();



// Require controller modules.

var book_controller = require('../controllers/bookController');

var author_controller = require('../controllers/authorController');

var genre_controller = require('../controllers/genreController');

var book_instance_controller = require('../controllers/bookinstanceController');



/// BOOK ROUTES ///



// GET catalog home page.

router.get('/', book_controller.index);



// GET request for creating a Book. NOTE This must come before routes that display Book (uses id).

router.get('/book/create', book_controller.book_create_get);



// POST request for creating Book.

router.post('/book/create', book_controller.book_create_post);



// GET request to delete Book.

router.get('/book/:id/delete', book_controller.book_delete_get);



// POST request to delete Book.

router.post('/book/:id/delete', book_controller.book_delete_post);



// GET request to update Book.

router.get('/book/:id/update', book_controller.book_update_get);



// POST request to update Book.

router.post('/book/:id/update', book_controller.book_update_post);



// GET request for one Book.

router.get('/book/:id', book_controller.book_detail);



// GET request for list of all Book items.

router.get('/books', book_controller.book_list);



/// AUTHOR ROUTES ///



// GET request for creating Author. NOTE This must come before route for id (i.e. display author).

router.get('/author/create', author_controller.author_create_get);



// POST request for creating Author.

router.post('/author/create', author_controller.author_create_post);



// GET request to delete Author.

router.get('/author/:id/delete', author_controller.author_delete_get);



// POST request to delete Author.

router.post('/author/:id/delete', author_controller.author_delete_post);



// GET request to update Author.

router.get('/author/:id/update', author_controller.author_update_get);



// POST request to update Author.

router.post('/author/:id/update', author_controller.author_update_post);



// GET request for one Author.

router.get('/author/:id', author_controller.author_detail);



// GET request for list of all Authors.

router.get('/authors', author_controller.author_list);



/// GENRE ROUTES ///



// GET request for creating a Genre. NOTE This must come before route that displays Genre (uses id).

router.get('/genre/create', genre_controller.genre_create_get);



//POST request for creating Genre.

router.post('/genre/create', genre_controller.genre_create_post);



// GET request to delete Genre.

router.get('/genre/:id/delete', genre_controller.genre_delete_get);



// POST request to delete Genre.

router.post('/genre/:id/delete', genre_controller.genre_delete_post);



// GET request to update Genre.

router.get('/genre/:id/update', genre_controller.genre_update_get);



// POST request to update Genre.

router.post('/genre/:id/update', genre_controller.genre_update_post);



// GET request for one Genre.

router.get('/genre/:id', genre_controller.genre_detail);



// GET request for list of all Genre.

router.get('/genres', genre_controller.genre_list);



/// BOOKINSTANCE ROUTES ///



// GET request for creating a BookInstance. NOTE This must come before route that displays BookInstance (uses id).

router.get('/bookinstance/create', book_instance_controller.bookinstance_create_get);



// POST request for creating BookInstance.

router.post('/bookinstance/create', book_instance_controller.bookinstance_create_post);



// GET request to delete BookInstance.

router.get('/bookinstance/:id/delete', book_instance_controller.bookinstance_delete_get);



// POST request to delete BookInstance.

router.post('/bookinstance/:id/delete', book_instance_controller.bookinstance_delete_post);



// GET request to update BookInstance.

router.get('/bookinstance/:id/update', book_instance_controller.bookinstance_update_get);



// POST request to update BookInstance.

router.post('/bookinstance/:id/update', book_instance_controller.bookinstance_update_post);



// GET request for one BookInstance.

router.get('/bookinstance/:id', book_instance_controller.bookinstance_detail);



// GET request for list of all BookInstance.

router.get('/bookinstances', book_instance_controller.bookinstance_list);



module.exports = router;

in app.js:

var createError = require('http-errors');

var express = require('express');

var path = require('path');

var cookieParser = require('cookie-parser');

var logger = require('morgan');



var indexRouter = require('./routes/index');

var usersRouter = require('./routes/users');

var catalogRouter = require('./routes/catalog');  //Import routes for "catalog" area of site



var app = express();



//Set up mongoose connection

var mongoose = require('mongoose');

var mongoDB = 'mongodb://dariusgoore:654321cg@ds145704.mlab.com:45704/local_library_dg';

mongoose.connect(mongoDB);

mongoose.Promise = global.Promise;

var db = mongoose.connection;

db.on('error', console.error.bind(console, 'MongoDB connection error:'));



// view engine setup

app.set('views', path.join(__dirname, 'views'));

app.set('view engine', 'pug');



app.use(logger('dev'));

app.use(express.json());

app.use(express.urlencoded({ extended: false }));

app.use(cookieParser());

app.use(express.static(path.join(__dirname, 'public')));



app.use('/', indexRouter);

app.use('/users', usersRouter);

app.use('/catalog', catalogRouter);  // Add catalog routes to middleware chain.



// catch 404 and forward to error handler

app.use(function(req, res, next) {

  next(createError(404));

});



// error handler

app.use(function(err, req, res, next) {

  // set locals, only providing error in development

  res.locals.message = err.message;

  res.locals.error = req.app.get('env') === 'development' ? err : {};



  // render the error page

  res.status(err.status || 500);

  res.render('error');

});



module.exports = app;

By process of elimination (and referenced in the error trace), the route that is causing the error is this one:

 // GET request for one Genre.

    router.get('/genre/:id', genre_controller.genre_detail);

Commenting out that route eliminates the error, but I can't tell why.

asked Jan 1 at 12:42

user2799827

818

First you should look at your controller, maybe one export is not a function as your error said...

– Pimento Web
Jan 1 at 15:38

add a comment |

Attempting to learn Expresss.js via this tutorial and I am at the point of adding routes. I believe I have followed the tutorial exactly, but I am getting this error:

[nodemon] starting `node ./bin/www`

/Users/dariusgoore/development/express-locallibrary-tutorial/node_modules/express/lib/router/route.js:202

    throw new Error(msg);

    ^



Error: Route.get() requires a callback function but got a [object  Undefined]

    at Route.(anonymous function) [as get] (/Users/dariusgoore/development/express-locallibrary-tutorial/node_modules/express/lib/router/route.js:202:15)

    at Function.proto.(anonymous function) [as get] (/Users/dariusgoore/development/express-locallibrary-tutorial/node_modules/express/lib/router/index.js:510:19)

    at Object.<anonymous> (/Users/dariusgoore/development/express-locallibrary-tutorial/routes/catalog.js:86:8)

    at Module._compile (internal/modules/cjs/loader.js:689:30)

    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)

    at Module.load (internal/modules/cjs/loader.js:599:32)

    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)

    at Function.Module._load (internal/modules/cjs/loader.js:530:3)

    at Module.require (internal/modules/cjs/loader.js:637:17)

    at require (internal/modules/cjs/helpers.js:22:18)

    at Object.<anonymous> (/Users/dariusgoore/development/express-locallibrary-tutorial/app.js:9:21)

    at Module._compile (internal/modules/cjs/loader.js:689:30)

    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)

    at Module.load (internal/modules/cjs/loader.js:599:32)

    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)

    at Function.Module._load (internal/modules/cjs/loader.js:530:3)

[nodemon] app crashed - waiting for file changes before starting...

Here are the relevant files:

routes/catalog.js

var express = require('express');

var router = express.Router();



// Require controller modules.

var book_controller = require('../controllers/bookController');

var author_controller = require('../controllers/authorController');

var genre_controller = require('../controllers/genreController');

var book_instance_controller = require('../controllers/bookinstanceController');



/// BOOK ROUTES ///



// GET catalog home page.

router.get('/', book_controller.index);



// GET request for creating a Book. NOTE This must come before routes that display Book (uses id).

router.get('/book/create', book_controller.book_create_get);



// POST request for creating Book.

router.post('/book/create', book_controller.book_create_post);



// GET request to delete Book.

router.get('/book/:id/delete', book_controller.book_delete_get);



// POST request to delete Book.

router.post('/book/:id/delete', book_controller.book_delete_post);



// GET request to update Book.

router.get('/book/:id/update', book_controller.book_update_get);



// POST request to update Book.

router.post('/book/:id/update', book_controller.book_update_post);



// GET request for one Book.

router.get('/book/:id', book_controller.book_detail);



// GET request for list of all Book items.

router.get('/books', book_controller.book_list);



/// AUTHOR ROUTES ///



// GET request for creating Author. NOTE This must come before route for id (i.e. display author).

router.get('/author/create', author_controller.author_create_get);



// POST request for creating Author.

router.post('/author/create', author_controller.author_create_post);



// GET request to delete Author.

router.get('/author/:id/delete', author_controller.author_delete_get);



// POST request to delete Author.

router.post('/author/:id/delete', author_controller.author_delete_post);



// GET request to update Author.

router.get('/author/:id/update', author_controller.author_update_get);



// POST request to update Author.

router.post('/author/:id/update', author_controller.author_update_post);



// GET request for one Author.

router.get('/author/:id', author_controller.author_detail);



// GET request for list of all Authors.

router.get('/authors', author_controller.author_list);



/// GENRE ROUTES ///



// GET request for creating a Genre. NOTE This must come before route that displays Genre (uses id).

router.get('/genre/create', genre_controller.genre_create_get);



//POST request for creating Genre.

router.post('/genre/create', genre_controller.genre_create_post);



// GET request to delete Genre.

router.get('/genre/:id/delete', genre_controller.genre_delete_get);



// POST request to delete Genre.

router.post('/genre/:id/delete', genre_controller.genre_delete_post);



// GET request to update Genre.

router.get('/genre/:id/update', genre_controller.genre_update_get);



// POST request to update Genre.

router.post('/genre/:id/update', genre_controller.genre_update_post);



// GET request for one Genre.

router.get('/genre/:id', genre_controller.genre_detail);



// GET request for list of all Genre.

router.get('/genres', genre_controller.genre_list);



/// BOOKINSTANCE ROUTES ///



// GET request for creating a BookInstance. NOTE This must come before route that displays BookInstance (uses id).

router.get('/bookinstance/create', book_instance_controller.bookinstance_create_get);



// POST request for creating BookInstance.

router.post('/bookinstance/create', book_instance_controller.bookinstance_create_post);



// GET request to delete BookInstance.

router.get('/bookinstance/:id/delete', book_instance_controller.bookinstance_delete_get);



// POST request to delete BookInstance.

router.post('/bookinstance/:id/delete', book_instance_controller.bookinstance_delete_post);



// GET request to update BookInstance.

router.get('/bookinstance/:id/update', book_instance_controller.bookinstance_update_get);



// POST request to update BookInstance.

router.post('/bookinstance/:id/update', book_instance_controller.bookinstance_update_post);



// GET request for one BookInstance.

router.get('/bookinstance/:id', book_instance_controller.bookinstance_detail);



// GET request for list of all BookInstance.

router.get('/bookinstances', book_instance_controller.bookinstance_list);



module.exports = router;

in app.js:

var createError = require('http-errors');

var express = require('express');

var path = require('path');

var cookieParser = require('cookie-parser');

var logger = require('morgan');



var indexRouter = require('./routes/index');

var usersRouter = require('./routes/users');

var catalogRouter = require('./routes/catalog');  //Import routes for "catalog" area of site



var app = express();



//Set up mongoose connection

var mongoose = require('mongoose');

var mongoDB = 'mongodb://dariusgoore:654321cg@ds145704.mlab.com:45704/local_library_dg';

mongoose.connect(mongoDB);

mongoose.Promise = global.Promise;

var db = mongoose.connection;

db.on('error', console.error.bind(console, 'MongoDB connection error:'));



// view engine setup

app.set('views', path.join(__dirname, 'views'));

app.set('view engine', 'pug');



app.use(logger('dev'));

app.use(express.json());

app.use(express.urlencoded({ extended: false }));

app.use(cookieParser());

app.use(express.static(path.join(__dirname, 'public')));



app.use('/', indexRouter);

app.use('/users', usersRouter);

app.use('/catalog', catalogRouter);  // Add catalog routes to middleware chain.



// catch 404 and forward to error handler

app.use(function(req, res, next) {

  next(createError(404));

});



// error handler

app.use(function(err, req, res, next) {

  // set locals, only providing error in development

  res.locals.message = err.message;

  res.locals.error = req.app.get('env') === 'development' ? err : {};



  // render the error page

  res.status(err.status || 500);

  res.render('error');

});



module.exports = app;

By process of elimination (and referenced in the error trace), the route that is causing the error is this one:

 // GET request for one Genre.

    router.get('/genre/:id', genre_controller.genre_detail);

Commenting out that route eliminates the error, but I can't tell why.

asked Jan 1 at 12:42

user2799827

818

First you should look at your controller, maybe one export is not a function as your error said...

– Pimento Web
Jan 1 at 15:38

add a comment |

Attempting to learn Expresss.js via this tutorial and I am at the point of adding routes. I believe I have followed the tutorial exactly, but I am getting this error:

[nodemon] starting `node ./bin/www`

/Users/dariusgoore/development/express-locallibrary-tutorial/node_modules/express/lib/router/route.js:202

    throw new Error(msg);

    ^



Error: Route.get() requires a callback function but got a [object  Undefined]

    at Route.(anonymous function) [as get] (/Users/dariusgoore/development/express-locallibrary-tutorial/node_modules/express/lib/router/route.js:202:15)

    at Function.proto.(anonymous function) [as get] (/Users/dariusgoore/development/express-locallibrary-tutorial/node_modules/express/lib/router/index.js:510:19)

    at Object.<anonymous> (/Users/dariusgoore/development/express-locallibrary-tutorial/routes/catalog.js:86:8)

    at Module._compile (internal/modules/cjs/loader.js:689:30)

    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)

    at Module.load (internal/modules/cjs/loader.js:599:32)

    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)

    at Function.Module._load (internal/modules/cjs/loader.js:530:3)

    at Module.require (internal/modules/cjs/loader.js:637:17)

    at require (internal/modules/cjs/helpers.js:22:18)

    at Object.<anonymous> (/Users/dariusgoore/development/express-locallibrary-tutorial/app.js:9:21)

    at Module._compile (internal/modules/cjs/loader.js:689:30)

    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)

    at Module.load (internal/modules/cjs/loader.js:599:32)

    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)

    at Function.Module._load (internal/modules/cjs/loader.js:530:3)

[nodemon] app crashed - waiting for file changes before starting...

Here are the relevant files:

routes/catalog.js

var express = require('express');

var router = express.Router();



// Require controller modules.

var book_controller = require('../controllers/bookController');

var author_controller = require('../controllers/authorController');

var genre_controller = require('../controllers/genreController');

var book_instance_controller = require('../controllers/bookinstanceController');



/// BOOK ROUTES ///



// GET catalog home page.

router.get('/', book_controller.index);



// GET request for creating a Book. NOTE This must come before routes that display Book (uses id).

router.get('/book/create', book_controller.book_create_get);



// POST request for creating Book.

router.post('/book/create', book_controller.book_create_post);



// GET request to delete Book.

router.get('/book/:id/delete', book_controller.book_delete_get);



// POST request to delete Book.

router.post('/book/:id/delete', book_controller.book_delete_post);



// GET request to update Book.

router.get('/book/:id/update', book_controller.book_update_get);



// POST request to update Book.

router.post('/book/:id/update', book_controller.book_update_post);



// GET request for one Book.

router.get('/book/:id', book_controller.book_detail);



// GET request for list of all Book items.

router.get('/books', book_controller.book_list);



/// AUTHOR ROUTES ///



// GET request for creating Author. NOTE This must come before route for id (i.e. display author).

router.get('/author/create', author_controller.author_create_get);



// POST request for creating Author.

router.post('/author/create', author_controller.author_create_post);



// GET request to delete Author.

router.get('/author/:id/delete', author_controller.author_delete_get);



// POST request to delete Author.

router.post('/author/:id/delete', author_controller.author_delete_post);



// GET request to update Author.

router.get('/author/:id/update', author_controller.author_update_get);



// POST request to update Author.

router.post('/author/:id/update', author_controller.author_update_post);



// GET request for one Author.

router.get('/author/:id', author_controller.author_detail);



// GET request for list of all Authors.

router.get('/authors', author_controller.author_list);



/// GENRE ROUTES ///



// GET request for creating a Genre. NOTE This must come before route that displays Genre (uses id).

router.get('/genre/create', genre_controller.genre_create_get);



//POST request for creating Genre.

router.post('/genre/create', genre_controller.genre_create_post);



// GET request to delete Genre.

router.get('/genre/:id/delete', genre_controller.genre_delete_get);



// POST request to delete Genre.

router.post('/genre/:id/delete', genre_controller.genre_delete_post);



// GET request to update Genre.

router.get('/genre/:id/update', genre_controller.genre_update_get);



// POST request to update Genre.

router.post('/genre/:id/update', genre_controller.genre_update_post);



// GET request for one Genre.

router.get('/genre/:id', genre_controller.genre_detail);



// GET request for list of all Genre.

router.get('/genres', genre_controller.genre_list);



/// BOOKINSTANCE ROUTES ///



// GET request for creating a BookInstance. NOTE This must come before route that displays BookInstance (uses id).

router.get('/bookinstance/create', book_instance_controller.bookinstance_create_get);



// POST request for creating BookInstance.

router.post('/bookinstance/create', book_instance_controller.bookinstance_create_post);



// GET request to delete BookInstance.

router.get('/bookinstance/:id/delete', book_instance_controller.bookinstance_delete_get);



// POST request to delete BookInstance.

router.post('/bookinstance/:id/delete', book_instance_controller.bookinstance_delete_post);



// GET request to update BookInstance.

router.get('/bookinstance/:id/update', book_instance_controller.bookinstance_update_get);



// POST request to update BookInstance.

router.post('/bookinstance/:id/update', book_instance_controller.bookinstance_update_post);



// GET request for one BookInstance.

router.get('/bookinstance/:id', book_instance_controller.bookinstance_detail);



// GET request for list of all BookInstance.

router.get('/bookinstances', book_instance_controller.bookinstance_list);



module.exports = router;

in app.js:

var createError = require('http-errors');

var express = require('express');

var path = require('path');

var cookieParser = require('cookie-parser');

var logger = require('morgan');



var indexRouter = require('./routes/index');

var usersRouter = require('./routes/users');

var catalogRouter = require('./routes/catalog');  //Import routes for "catalog" area of site



var app = express();



//Set up mongoose connection

var mongoose = require('mongoose');

var mongoDB = 'mongodb://dariusgoore:654321cg@ds145704.mlab.com:45704/local_library_dg';

mongoose.connect(mongoDB);

mongoose.Promise = global.Promise;

var db = mongoose.connection;

db.on('error', console.error.bind(console, 'MongoDB connection error:'));



// view engine setup

app.set('views', path.join(__dirname, 'views'));

app.set('view engine', 'pug');



app.use(logger('dev'));

app.use(express.json());

app.use(express.urlencoded({ extended: false }));

app.use(cookieParser());

app.use(express.static(path.join(__dirname, 'public')));



app.use('/', indexRouter);

app.use('/users', usersRouter);

app.use('/catalog', catalogRouter);  // Add catalog routes to middleware chain.



// catch 404 and forward to error handler

app.use(function(req, res, next) {

  next(createError(404));

});



// error handler

app.use(function(err, req, res, next) {

  // set locals, only providing error in development

  res.locals.message = err.message;

  res.locals.error = req.app.get('env') === 'development' ? err : {};



  // render the error page

  res.status(err.status || 500);

  res.render('error');

});



module.exports = app;

By process of elimination (and referenced in the error trace), the route that is causing the error is this one:

 // GET request for one Genre.

    router.get('/genre/:id', genre_controller.genre_detail);

Commenting out that route eliminates the error, but I can't tell why.

asked Jan 1 at 12:42

user2799827

818

Attempting to learn Expresss.js via this tutorial and I am at the point of adding routes. I believe I have followed the tutorial exactly, but I am getting this error:

[nodemon] starting `node ./bin/www`

/Users/dariusgoore/development/express-locallibrary-tutorial/node_modules/express/lib/router/route.js:202

    throw new Error(msg);

    ^



Error: Route.get() requires a callback function but got a [object  Undefined]

    at Route.(anonymous function) [as get] (/Users/dariusgoore/development/express-locallibrary-tutorial/node_modules/express/lib/router/route.js:202:15)

    at Function.proto.(anonymous function) [as get] (/Users/dariusgoore/development/express-locallibrary-tutorial/node_modules/express/lib/router/index.js:510:19)

    at Object.<anonymous> (/Users/dariusgoore/development/express-locallibrary-tutorial/routes/catalog.js:86:8)

    at Module._compile (internal/modules/cjs/loader.js:689:30)

    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)

    at Module.load (internal/modules/cjs/loader.js:599:32)

    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)

    at Function.Module._load (internal/modules/cjs/loader.js:530:3)

    at Module.require (internal/modules/cjs/loader.js:637:17)

    at require (internal/modules/cjs/helpers.js:22:18)

    at Object.<anonymous> (/Users/dariusgoore/development/express-locallibrary-tutorial/app.js:9:21)

    at Module._compile (internal/modules/cjs/loader.js:689:30)

    at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)

    at Module.load (internal/modules/cjs/loader.js:599:32)

    at tryModuleLoad (internal/modules/cjs/loader.js:538:12)

    at Function.Module._load (internal/modules/cjs/loader.js:530:3)

[nodemon] app crashed - waiting for file changes before starting...

Here are the relevant files:

routes/catalog.js

var express = require('express');

var router = express.Router();



// Require controller modules.

var book_controller = require('../controllers/bookController');

var author_controller = require('../controllers/authorController');

var genre_controller = require('../controllers/genreController');

var book_instance_controller = require('../controllers/bookinstanceController');



/// BOOK ROUTES ///



// GET catalog home page.

router.get('/', book_controller.index);



// GET request for creating a Book. NOTE This must come before routes that display Book (uses id).

router.get('/book/create', book_controller.book_create_get);



// POST request for creating Book.

router.post('/book/create', book_controller.book_create_post);



// GET request to delete Book.

router.get('/book/:id/delete', book_controller.book_delete_get);



// POST request to delete Book.

router.post('/book/:id/delete', book_controller.book_delete_post);



// GET request to update Book.

router.get('/book/:id/update', book_controller.book_update_get);



// POST request to update Book.

router.post('/book/:id/update', book_controller.book_update_post);



// GET request for one Book.

router.get('/book/:id', book_controller.book_detail);



// GET request for list of all Book items.

router.get('/books', book_controller.book_list);



/// AUTHOR ROUTES ///



// GET request for creating Author. NOTE This must come before route for id (i.e. display author).

router.get('/author/create', author_controller.author_create_get);



// POST request for creating Author.

router.post('/author/create', author_controller.author_create_post);



// GET request to delete Author.

router.get('/author/:id/delete', author_controller.author_delete_get);



// POST request to delete Author.

router.post('/author/:id/delete', author_controller.author_delete_post);



// GET request to update Author.

router.get('/author/:id/update', author_controller.author_update_get);



// POST request to update Author.

router.post('/author/:id/update', author_controller.author_update_post);



// GET request for one Author.

router.get('/author/:id', author_controller.author_detail);



// GET request for list of all Authors.

router.get('/authors', author_controller.author_list);



/// GENRE ROUTES ///



// GET request for creating a Genre. NOTE This must come before route that displays Genre (uses id).

router.get('/genre/create', genre_controller.genre_create_get);



//POST request for creating Genre.

router.post('/genre/create', genre_controller.genre_create_post);



// GET request to delete Genre.

router.get('/genre/:id/delete', genre_controller.genre_delete_get);



// POST request to delete Genre.

router.post('/genre/:id/delete', genre_controller.genre_delete_post);



// GET request to update Genre.

router.get('/genre/:id/update', genre_controller.genre_update_get);



// POST request to update Genre.

router.post('/genre/:id/update', genre_controller.genre_update_post);



// GET request for one Genre.

router.get('/genre/:id', genre_controller.genre_detail);



// GET request for list of all Genre.

router.get('/genres', genre_controller.genre_list);



/// BOOKINSTANCE ROUTES ///



// GET request for creating a BookInstance. NOTE This must come before route that displays BookInstance (uses id).

router.get('/bookinstance/create', book_instance_controller.bookinstance_create_get);



// POST request for creating BookInstance.

router.post('/bookinstance/create', book_instance_controller.bookinstance_create_post);



// GET request to delete BookInstance.

router.get('/bookinstance/:id/delete', book_instance_controller.bookinstance_delete_get);



// POST request to delete BookInstance.

router.post('/bookinstance/:id/delete', book_instance_controller.bookinstance_delete_post);



// GET request to update BookInstance.

router.get('/bookinstance/:id/update', book_instance_controller.bookinstance_update_get);



// POST request to update BookInstance.

router.post('/bookinstance/:id/update', book_instance_controller.bookinstance_update_post);



// GET request for one BookInstance.

router.get('/bookinstance/:id', book_instance_controller.bookinstance_detail);



// GET request for list of all BookInstance.

router.get('/bookinstances', book_instance_controller.bookinstance_list);



module.exports = router;

in app.js:

var createError = require('http-errors');

var express = require('express');

var path = require('path');

var cookieParser = require('cookie-parser');

var logger = require('morgan');



var indexRouter = require('./routes/index');

var usersRouter = require('./routes/users');

var catalogRouter = require('./routes/catalog');  //Import routes for "catalog" area of site



var app = express();



//Set up mongoose connection

var mongoose = require('mongoose');

var mongoDB = 'mongodb://dariusgoore:654321cg@ds145704.mlab.com:45704/local_library_dg';

mongoose.connect(mongoDB);

mongoose.Promise = global.Promise;

var db = mongoose.connection;

db.on('error', console.error.bind(console, 'MongoDB connection error:'));



// view engine setup

app.set('views', path.join(__dirname, 'views'));

app.set('view engine', 'pug');



app.use(logger('dev'));

app.use(express.json());

app.use(express.urlencoded({ extended: false }));

app.use(cookieParser());

app.use(express.static(path.join(__dirname, 'public')));



app.use('/', indexRouter);

app.use('/users', usersRouter);

app.use('/catalog', catalogRouter);  // Add catalog routes to middleware chain.



// catch 404 and forward to error handler

app.use(function(req, res, next) {

  next(createError(404));

});



// error handler

app.use(function(err, req, res, next) {

  // set locals, only providing error in development

  res.locals.message = err.message;

  res.locals.error = req.app.get('env') === 'development' ? err : {};



  // render the error page

  res.status(err.status || 500);

  res.render('error');

});



module.exports = app;

By process of elimination (and referenced in the error trace), the route that is causing the error is this one:

 // GET request for one Genre.

    router.get('/genre/:id', genre_controller.genre_detail);

Commenting out that route eliminates the error, but I can't tell why.

express routes

asked Jan 1 at 12:42

user2799827

818

asked Jan 1 at 12:42

user2799827

818

asked Jan 1 at 12:42

user2799827

818

asked Jan 1 at 12:42

user2799827

818

asked Jan 1 at 12:42

user2799827

818

First you should look at your controller, maybe one export is not a function as your error said...

– Pimento Web
Jan 1 at 15:38

add a comment |

First you should look at your controller, maybe one export is not a function as your error said...

– Pimento Web
Jan 1 at 15:38

First you should look at your controller, maybe one export is not a function as your error said...

– Pimento Web
Jan 1 at 15:38

add a comment |

1 Answer
1

active

oldest

votes

Figured this out. the controller spelled the action differently.

The router line above references genre_controller.genre_detail

whereas the controller exported genre_details

changing details to detail in the controller solves this issue.

answered Jan 3 at 17:26

user2799827

818

add a comment |

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1 Answer
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active

oldest

votes

1 Answer
1

active

oldest

votes

Figured this out. the controller spelled the action differently.

The router line above references genre_controller.genre_detail

whereas the controller exported genre_details

changing details to detail in the controller solves this issue.

answered Jan 3 at 17:26

user2799827

818

add a comment |

Figured this out. the controller spelled the action differently.

The router line above references genre_controller.genre_detail

whereas the controller exported genre_details

changing details to detail in the controller solves this issue.

answered Jan 3 at 17:26

user2799827

818

add a comment |

Figured this out. the controller spelled the action differently.

The router line above references genre_controller.genre_detail

whereas the controller exported genre_details

changing details to detail in the controller solves this issue.

answered Jan 3 at 17:26

user2799827

818

Figured this out. the controller spelled the action differently.

The router line above references genre_controller.genre_detail

whereas the controller exported genre_details

changing details to detail in the controller solves this issue.

answered Jan 3 at 17:26

user2799827

818

answered Jan 3 at 17:26

user2799827

818

answered Jan 3 at 17:26

user2799827

818

answered Jan 3 at 17:26

user2799827

818

add a comment |

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