Node Modules 依赖优化处理

开发Node.js项目时候，拷贝项目文件夹的时候发现竟然出现了Windows下文件名过长的问题。经过研究以后发现这个问题是项目目录当中的node_modules目录下组件间依赖关系导致的。

查看node_modules属性发现使用Yoeman创建的项目MyDemo初始就有大约80M，其中的依赖情况可以使用npm list查看

f:\MyDemo>npm list 

情况大约是

[email protected]
├─┬ [email protected]
│ ├── [email protected]
│ ├── [email protected]
│ ├── [email protected]
│ ├── [email protected]
│ ├── [email protected]
│ ├── [email protected]
│ ├─┬ [email protected]
│ │ ├─┬ [email protected]
│ │ │ └── [email protected]
│ │ └── [email protected]
....省略

结果就是依赖模块套依赖模块，有的模块依赖层次太深，因此项目目录出现文件名过长。

解决问题的思路参考 这里

1. 使用npm 获取所有的依赖情况
2. 检查模块的重复情况，需要带上版本号
3. 使用npm install module@version --save-dev将重复的模块依赖更新到项目的package.json文件当中
4. 删除项目当中的node_modules文件夹(我的例子f:\MyDemo\node_modules)
5. 使用npm install重新安装node_modules目录

按这个思路处理完毕以后原来80多M的node_modules减肥为40多M，拷贝项目文件可以支持更深一点的目录了。
注意：处理一遍以后重复依赖大大减少，使用npm list 可以看出依然还有重复依赖。

我npm list 出来的信息有700多，咱不能用眼睛看吧？因此就有了下面的这个工具类：

1.使用npm list > c:/node_depend.txt

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * find duplicate modules in node.js projects
 * 
 * <pre>
 * 1. npm ls to get a list of all installed modules.
 * 2.look through those modules and identify duplicate modules (version is important)
 * 3.npm install module@version --save-dev to install those modules in the root node_modules
 *  directory and update package.json.
 * 4.rmdir node_modules to delete the node_modules directory.
 * 5.npm install to pull down a fresh copy of your dependencies.
 * </pre>
 * 
 * RefURL:http://stackoverflow.com/questions/13318364/how-to-deploy-node-js-
 * application-with-deep-node-modules-structure-on-windows?rq=1
 * 
 * @author [email protected]
 * 
 */
public class FindDupeModue {

    public static void main(String[] args) {
        String fileName = "c:/node_depend.txt";
        List<String> moduleList = getModules(fileName);
        List<String> dupeModue = checkDupeModue(moduleList);
        printResult(dupeModue);
    }

    /**
     * read modules from file
     * 
     * @param fileName
     * @return
     */
    private static List<String> getModules(String fileName) {
        List<String> list = new CopyOnWriteArrayList<String>();
        BufferedReader br = null;
        String s = null;
        try {
            br = new BufferedReader(new FileReader(new File(fileName)));
            while ((s = br.readLine()) != null) {
                list.add(format(s));
            }
            br.close();
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } finally {
            if (br != null) {
                try {
                    br.close();
                } catch (IOException e1) {
                    // TODO Auto-generated catch block
                    e1.printStackTrace();
                }
            }
        }
        return list;
    }

    /**
     * format nodeName
     * 
     * @param modulName
     * @return
     */
    private static String format(String modulName) {
        String patternString = "[^A-Z|^a-z|^0-9|^.|^@|^-]";
        Pattern pattern = Pattern.compile(patternString);
        Matcher matcher = pattern.matcher(modulName);
        return matcher.replaceAll("");
    }

    /**
     * check out the DupeModue
     * 
     * @param moduleList
     * @return
     */
    private static List<String> checkDupeModue(List<String> moduleList) {
        System.out
                .println("==========Begin Find DupeModule===================");
        List<String> list = new ArrayList<String>();
        for (String item : moduleList) {
            // check in moduleList
            List<String> allDupeList = getAllDupeModue(moduleList, item);
            if (allDupeList.size() > 1) {
                System.out.println(item + "=" + allDupeList.size());
                list.add(item);
                moduleList.removeAll(allDupeList);
            } else {
                moduleList.remove(item);
            }
        }
        System.out.println("==========End Find DupeModule===================");
        return list;
    }

    /**
     * loop in moduleList
     * 
     * @param moduleList
     * @param item
     * @return
     */
    private static List<String> getAllDupeModue(List<String> moduleList,
            String moduleName) {
        List<String> tmpList = new ArrayList<String>();
        for (String item : moduleList) {
            if (moduleName.equals(item)) {
                tmpList.add(item);
            }
        }
        return tmpList;
    }

    /**
     * printResult
     * npm install module@version --save-dev
     * 
     * @param moduleList
     */
    private static void printResult(List<String> moduleList) {
        System.out.println("=============Result===================");
        for (String item : moduleList) {
            System.out.println("npm install " + item + " --save-dev");
        }
    }
}

2.运行工具类看重复情况

==========Begin Find DupeModule===================
[email protected]=2
[email protected]=6
[email protected]=5
[email protected]=5
....(省略)
=============Result===================
npm install [email protected] --save-dev
npm install [email protected] --save-dev
npm install [email protected] --save-dev
npm install [email protected] --save-dev
npm install [email protected] --save-dev
...(省略)

Enjoy it!