Node.js, TypeError: xxx is not a function, in require'd file

Question

I have two files (for example).

./database/user.js

module.exports = {
    getUniqueByID: function(params){
        doSomething();
        return anUserObject;
    }
};

./database/uperm.js

var dbUser = require('./user.js');
module.exports = {
    createNew: function(params){
        dbUser.getUniqueByID(uid);
        doSomethingElse();
    }
};

Function createNew() from uperm.js always throws an exception:

.../uperm.js:123
dbUser.getUniqueByID(uid);
TypeError: dbUser.getUniqueByID is not a function

But, if i change ./database/uperm.js to be:

module.exports = {
    createNew: function(params){
        require('./user.js').getUniqueByID(uid);
        doSomethingElse();
    }
};

Then getUniqueByID() from user.js is called by createNew() from uperm.js, without any exception.

But I don't whant to use require('./user.js') everywhere, instead of assigning it to dbUser variable.

What's wrong in case of using variable? Absolutely similar code in other files of my project seems to be ok.

Don't you have circular references between modules? It seems that you do. — Dmitriy Simushev, Apr 08 '16 at 13:36
Yes, that's true. file1 require's file2 and file2 require's file1 as well. — Denis Golovkin, Apr 08 '16 at 21:54
More than this... File1 depends on file1 and file 2 AND file2 depend on file1 and file2 as well. — Denis Golovkin, Apr 08 '16 at 22:55

score 2 · Accepted Answer · edited May 23 '17 at 12:15

2

Since you have circular dependencies, try to set properties of the module.exports instead of directly overwriting it:

var functions = {
   getUniqueByID: xxx
};

for(var key in functions) {
    module.exports[key] = functions[key];
}

(From the idea provided in this answer)

edited May 23 '17 at 12:15

Community

1
1

answered Apr 08 '16 at 14:02

christophetd

3,834
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33

I've tryed var foos = { getUniqueByID: xxx }; module.exports = foos; ... But this does't help. Your solution works even if file1 depends on file1 and file2 and file 2 depends on file1 and file2 as well. Thank you again. – Denis Golovkin Apr 08 '16 at 22:52

Node.js, TypeError: xxx is not a function, in require'd file

1 Answers1