Undefined 'callback' with Async Waterfall / Node.js

Question

I am trying to get a waterfall working in Node.js using Async but I keep getting the error

callback (null, articleDataSafe, req); ^ TypeError: undefined is not a function

The code is as follows

async.waterfall([
                        function sanitizeData (articleData, req, callback) {

                                articleDataSafe = sanitizeArticle(articleData);
                                console.log('s1');
                                callback (null, articleDataSafe, req);

                        },

                        function _validateData (articleDataSafe, req, callback) {

                               var errors = validateArticle(articleData);
                               var err = null;
                               if(errors.length > 0){
                                    // return error messages back to the browser
                                    err = JSON.stringify({'error': errors, "message": "fail"});
                                 };
                                console.log('s2');

                               callback (err, articleDataSafe, req);

                        },

                        function _saveArticle (articleDataSafe, req, callback) {

                                // work out the tags hash
                                var tags = articleDataSafe['tags'];
                                var tagsArray = tags.split(",");
                                tagsArray.sort();
                                var tagsString = tagsArray.join(); 
                                var hashedTags = sha512(tagsString);
                                articleDataSafe['hashedTags'] = hashedTags;

                                // then save the articles
                                var savedArticle = saveArticle(req, articleDataSafe);

                                console.log('s3');

                                if(!savedArticle){
                                    var err = JSON.stringify({'error': 'notSaveArticle', 'message': 'fail'});
                                }

                                callback (err, articleDataSafe);

                        },

                        function _saveTags (articleDataSafe, callback) {

                                var tagsDone = saveTags(articleDataSafe);

                                if(tagsDone.length > 0){
                                    // return error messages back to the browser
                                    var err = JSON.stringify({'error': tagsDone, "message": "fail"});
                                 };
                                console.log('s4');

                                callback (err, articleDataSafe);

                        },

                        function _saveTagSets (articleDataSafe, callback) {

                                var tagSetsDone = saveTagSets(data);

                                if(tagSetsDone.length > 0){
                                    // return error messages back to the browser
                                    var err = JSON.stringify({'error': errors, "message": "fail"});
                                 };
                                console.log('s5');

                                callback (err, articleDataSafe);

                        }
                    ], function (error, success) {

                        var responseMessage = {'error': '', "message": "success"};

                        if (error) { 
                            responseMessage = error; 
                        } 

                        res.end(JSON.stringify(responseMessage));

                    });

Can any explain what is going wrong. I have been trying for ages now to get it working with no luck.

Any help will be appreciated.

Thanks, Cs1h

Wait, why are you using async.waterfall at all when you have nothing asynchronous to do? — Bergi
– Bergi, Commented Feb 3, 2015 at 21:15

Bergi · Accepted Answer · 2015-02-03 21:18:52Z

3

The first function is passed no other argument than the callback. You'd need to start like this:

async.waterfall([
    function sanitizeData (callback) {
//                        ^^^^^^^^^^ no articleData, no req
        articleDataSafe = sanitizeArticle(articleData);
        console.log('s1');
        callback (null, articleDataSafe, req);
    },
    …

However I doubt you need async at all.

answered Feb 3, 2015 at 21:18

Bergi

671k162 gold badges1k silver badges1.5k bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

cs1h Over a year ago

Thanks Bergi, that seems to work. I will need async later on for more complex matters but I wanted to use with something more simple first.

randomness Over a year ago

Thanks @Bergi . This solved a bugging careless mistake i was sitting on

Collectives™ on Stack Overflow

Undefined 'callback' with Async Waterfall / Node.js

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related