Chapter 4 cleanup.

README.md

@@ -17,3 +17,7 @@ The [Chapter 2 Examples](ch02/README.md) demonstrate a simple, minimal web serve
 ### Chapter 3
 
 The [Chapter 3 Examples](ch03/README.md) demonstrate a simple, minimal web server using Express.
+
+### Chapter 4
+
+The [Chapter 4 Example](ch03/README.md) take the "fortune cookie" functionality deveoped in Chapter 3, and implement it as a Node module.

ch04/README.md

@@ -0,0 +1,23 @@
+# Chapter 4 Examples - Web Development with Node and Express, 2nd Edition
+
+## Using Node Modules
+
+This chapter is mostly background information, so there's only one example in this chapter; taking the "fortunte cookie" functionality that was developed in Chapter 3, and placing it in a Node module.  See _lib/fortune.js_ and _meadowlark.js_.
+
+### Setup
+
+The example in this chapter has Node module dependencies (`express` and `express-handlebars`).  These dependencies are listed in the _package.json_ file.  However, when you first clone this repo, you won't have them installed (_package.json_ is simply a manifest).  To install them, simply run:
+
+```
+npm install
+```
+
+### Running
+
+Minimal example; uses Express, but doesn't do very much.  To run:
+
+```
+node 00-meadowlark
+```
+
+Then visit _http://localhost:3000/about_ in your browser.

ch04/lib/fortune.js

@@ -5,6 +5,7 @@ const fortuneCookies = [
   "You will have a pleasant surprise.",
   "Whenever possible, keep it simple.",
 ]
+
 exports.getFortune = () => {
   const idx = Math.floor(Math.random()*fortuneCookies.length)
   return fortuneCookies[idx]