development of plugin to display file by providing the file path , get error "undefined" in index.js generated by gitbook

[Veronicatt]

Recently, I was assigned to develop a customized plugin for gitbook https://github.com/GitbookIO/gitbook to display the file by providing the path in the README.md , The plugin example is right here :https://github.com/GitbookIO/plugin ,the plugin is supposed to work like :

the link in the README.md : ["hello.java"](src/to/hello.java)=======> after build the gitbook ,it turns to

public class Hello{
    public static void main(String []args){
        System.out.println("Hello");
    }
}

Then In my plugin package, I modify the index.js file like this

module.exports = {
book: {
    assets: "./book",
    js: [
    "test.js"
    ],
    css: [
    "test.css"
    ],
    html: {
        "html:start": function() {
            return "<!-- Start book "+this.options.title+" -->"
        },
        "html:end": function() {
            return "<!-- End of book "+this.options.title+" -->"
        },

        "head:start": "<!-- head:start -->",
        "head:end": "<!-- head:end -->",

        "body:start": "<!-- body:start -->",
        "body:end": "<!-- body:end -->"
    }
},
hooks: {
    // For all the hooks, this represent the current generator

    // This is called before the book is generated
    "init": function() {
        console.log("init!");
        },

    // This is called after the book generation
    "finish": function() {
        console.log("finish!");
    },

    // The following hooks are called for each page of the book
    // and can be used to change page content (html, data or markdown)

    // Before parsing markdown
    "page:before": function(page) {

        console.log("============="+ page.content +"===============");

        var pathlist= page.content.match(/\[\"[A-Za-z]*\.[A-Za-z]*\"\]\([A-Za-z\/\-\d]*\.[A-Za-z]*\)/g);

        if (pathlist) {
            console.log( "The length of the match array is " + pathlist.length +" and the content of the array is "+ pathlist);
        }


        if (pathlist && pathlist.length > 0){

            for (index = 0; index <pathlist.length; index++){

                var fs = require("node-fs");
                var index1 = pathlist[index].indexOf("(");
                var index2 = pathlist[index].indexOf(")");
                var sub_string = pathlist[index].substr(index1+1,index2-index1-1);
                var pathToFile = sub_string;

                console.log(pathToFile);

                if(fs.existsSync(pathToFile)){ 

                    console.log("@@@@@@@@@@@@@@@@"+ pathToFile);

                    if(fs.statSync(pathToFile)){

                        try {
                            fs.openSync(pathToFile, "r")
                            }catch(e){
                                console.log('Error:', e);
                                return;
                                }                

                            console.log("Let's print out the source code below , Seeeeeeeeeeeeee");

                            var data = fs.readFileSync(pathToFile).toString();

                            console.log(data);

                            pathlist[index]=data;
                        }
                    };

            }}
            console.log("here is the results array:||||||||||||||||| " + pathlist +"|||||||||||||||||||||||||||||");

            var pattern = /\[\"[A-Za-z]*\.[A-Za-z]*\"\]\([A-Za-z\/\-\d]*\.[A-Za-z]*\)/;

            var input = page.content;

            for (var i = 0; i < pathlist.length; i++) {

                input = input.replace(pattern, "`"+pathlist[i]+"`");    
            }
        page.content = input;
        console.log(page.content);
        return page;    
    },
    "page": function(page) {
        console.log("page");
    },
    "page:after": function(page) {
        console.log("after");
    }           
  }
};  

then I add the plugin folder which I named "hello" in my node_modules folder and excute

npm install path/to/plugin-hello

in my book directory , I add the plugin configuration in the book.json

{
"plugins"       : ["richquotes", "hello"],
"pluginsConfig":{
    "richquotes" :{
        "todos" : true,
        "fixme" : true,
        "info"  : true
    },
    "hello": {}
    }
}

When I build the gitbook the log is look like this:

C02KG1DGFFT3:gitbooktest v619896$ gitbook build ./
Starting build ...
init!
=============gitbooktobedeleted
==================

This is a gitbook for testing

> **todo**
>


["ContactController.java"](ContactController.java)

["web.xml"](src/to/web.xml)
===============
The length of the match array is 2 and the content of the array is ["ContactController.java"]  
(ContactController.java),["web.xml"](src/to/web.xml)
ContactController.java
@@@@@@@@@@@@@@@@ContactController.java
##################
Let's print out the source code below , Seeeeeeeeeeeeee
public class ContactController{
public static void main(String []args){
    System.out.println("Hello");
 }
}
 src/to/web.xml
 @@@@@@@@@@@@@@@@src/to/web.xml
 ##################
 Let's print out the source code below , Seeeeeeeeeeeeee
 <%%%%?xml%%%%version="1.0" encoding="UTF-8"?>
 <web-app xmlns="http://java.sun.com/xml/ns/javaee"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee

/web-app_3_0.xsd"
     version="3.0">
</web-app>
here is the results array:||||||||||||||||| public class ContactController{
public static void main(String []args){
    System.out.println("Hello");
}
},<%%%%?xml%%%%version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/n/javaee      
/web-app_3_0.xsd"
     version="3.0">
</web-app>|||||||||||||||||||||||||||||
gitbooktobedeleted
==================

This is a gitbook for testing

> **todo**
>


`public class ContactController{
   public static void main(String []args){
    System.out.println("Hello");
    }
}`

`<%%%%?xml%%%%version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/n/javaee      
/web-app_3_0.xsd"
     version="3.0">
</web-app>`

page
after
finish!
Successfully built!

It looks like everything works fine !

but when I try to open the index.html it generated , the page content is "undefined " and nothing else !

Could anyone give me some hint ,where did I make the mistake ? I am really new to Javascript ! Thanks!