Since JavaScript is a dynamically typed language, module imports in node.js are not statically checked for correctness: calls to require simply return an object containing all the exports of the imported module, and accessing a member that was not, in fact, exported, yields undefined. This is most likely unintentional and usually indicates a bug.

Examine the import in question and determine the correct name of the symbol to import.

In the following example, module point.js exports the function Point by assigning it to module.exports. The client module client.js tries to import it by reading from the Point property, but since this property does not exist the result will be undefined, and the new invocation will fail.

Instead of reading the Point property, client.js should directly use the result of the require call:

Node.js Manual: Modules.