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Hey, how'd it go?

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Hopefully you're able to complete
this challenge successfully.

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The goal was to break up app.js by
abstracting the route handlers,

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error handlers and helper functions
into the respective modules.

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Then you had to import and use the route
and error handlers in app.js and

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use the helpers in a routes.js file.

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Now, I'll show you my solution,
which you can compare to what you wrote.

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You can also reference all my code
when you download the project files.

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All right, let's start with the routes.

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I created a file named routes.js.

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And in routes.js, I imported express and

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setup express.Router up top then
moved the two get method routes for

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the home and error routes from app.js and
into routes.js.

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I adjusted the route handlers to work
on the router rather than app, for

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example router.get.

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Then I exported the router using
the module.exports property.

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Now module.exports instructs Node JS which
parts of the code to export from the file,

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whether it's a function object,
string and so on.

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That way other files are allowed
to access the exported code.

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So to export the router from routes.js, I
assigned module.exports the router object.

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Then I imported the routes
module into app.js.

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You Import and load code from one file
into another file in Node using require.

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So to import code from the routes file,
I pass the file's path to require.

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Then I use the app.use method to pass
the new routes module to the Express app.

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Next, to modularize the error handlers,
I created a file named errorHandler.js.

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Remove those callback
functions in the 404 and

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global error handlers from app.js and
added them to errorHandlers.js.

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And I had to adjust the callback so

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that there are named functions
that can be exported.

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So I, for example, named them
handleFourOhFour and handleGlobalError.

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Then I exported the named error handler
functions from errorHandlers.js

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by assigning module.exports an object
that references each function.

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And I imported the error
handlers module into app.js and

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assigned it to the constant errorHandlers.

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After that I pass the exported functions
into the app.use statements for

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the 404 and global error handlers
with errorHandlers.handleFourOhFour,

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and errorHandlers.handleGlobalError.

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Modules also help you organize related
functions together into a file.

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So I created a file named helpers.js,

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which contains functions you can import
in any file that needs to use a helper.

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I moved the reverseString and
shortenString functions from app.js

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into helpers.js, and
similar to the error handlers,

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I exported the named helper functions by
assigning module.exports an object that

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references each function, and I imported
the helpers module into routes.js.

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Finally, I had to replace the helper
function calls in the route or home route

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handler, with calls to the exported helper
functions from the helpers.js module.

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When you export a function
with a module.exports,

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you can call it as you would any function,
in this case, helpers.reverseString and

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helpers.shortenString.

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As I mentioned earlier, there are multiple
ways to export and import a module.

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So you may have used a different
approach to import or

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export your error handlers and
helpers, and that's okay.

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In fact, the next step of this workshop
provides a few more examples of

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the various ways you could export and
import each module.

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All right, so

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I hope that you were able to complete this
modules practice session successfully.

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If not, why not start over and try it
again without looking at my version?

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You're also going to learn more
about working with modules

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as you progress through our full
stack JavaScript curriculum.

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Thanks everyone, and happy learning.