node.js - 使用 NodeJS 打包 epub

Question

我正在开发一个小型 Nodejs 应用程序，它可以解压 epub、修改标题，然后重新打包。

拆包和修改工作。当我使用 npm 包“archiver”重新打包时，存档文件似乎已损坏。它无法由电子阅读器打开或由压缩实用程序解包。

如果我在独立的 js 文件中使用相同的代码打包目录，它可以正常工作。

在主应用程序内，我使用以下代码来调用每个模块(解压缩、重命名、重新压缩)。据我所知，这是此应用程序中的代码(不起作用)与独立文件中的代码(起作用)之间的唯一区别。

var unzip = require('../services/unzip');
var replacetitle = require('../services/replacetitle');
var rezip = require('../services/rezip');    

fileObject = {};
fileObject.unzipPath = "/Users/me/Downloads/myPath/";
fileObject.filePath = "/Users/me/Downloads";
fileObject.novelTitle = "myFile";

unzip.unzip(fileObject)
    .then( 
        replacetitle.replacetitle(fileObject) 
    ).then(
        rezip.rezip(fileObject)
    );

这是来自 rezip.js 的代码(不起作用):

var fs = require("fs");
var archiver = require("archiver");

module.exports = {
    rezip: function(fileObject){

        var path = fileObject.unzipPath;
        var outputPath = fileObject.filePath + '/' + fileObject.novelTitle + '.epub';
        var output = fs.createWriteStream(outputPath);
        var archive = archiver("zip");

        // pipe archive data to the file
        archive.pipe(output);

        // add the mimetype file.  This MUST be the first file added
        archive.file(path + "mimetype", { name: "mimetype" });

        // append the other files and folders
        var files = fs.readdirSync(path);

        // Loop through each item in the directory, determine if
        // it is a file or a directory and append accordingly
        function fileAppender(fileIndex) {
            if (fileIndex < files.length) {
                var stat = fs.statSync(path + files[fileIndex]);
                if (stat.isFile()) {
                    if (
                        files[fileIndex] !== "mimetype" &&
                        files[fileIndex] !== ".DS_Store"
                    ) {
                        archive.file(path + files[fileIndex], { name: files[fileIndex] });
                    }
                } else if (stat.isDirectory()) {
                    archive.directory(path + files[fileIndex], files[fileIndex]);
                }
                fileAppender(fileIndex + 1);

            } else {
                // finalize the archive (ie we are done appending files but streams have to finish yet)
                // 'close', 'end' or 'finish' may be fired right after calling this method so register to them beforehand
                archive.finalize();
                return new Promise(function(resolve, reject){
                    resolve(fileObject);
                })
            }
        }
        fileAppender(0);
    }
}

下面是来自独立文件的有效代码。在调试器中观察其中的每一个，它们以相同的方式执行，只有一个输出可以使用电子阅读器或存档实用程序打开的文件，而另一个输出似乎已损坏的文件。

fileObject = {
    path: "/Users/me/Downloads/myPath/",
    outputPath: "/Users/me/Downloads/myPath/myFile.epub"
}
var fs = require("fs");
var archiver = require("archiver");

var path = fileObject.path;
var outputPath = fileObject.outputPath;
var output = fs.createWriteStream(outputPath);
var archive = archiver("zip");

// pipe archive data to the file
archive.pipe(output);

// add the mimetype file.  This MUST be the first file added
archive.file(path + "mimetype", { name: "mimetype" });

// append the other files and folders
var files = fs.readdirSync(path);

// Loop through each item in the directory, determine if
// it is a file or a directory and append accordingly
function fileAppender(fileIndex) {
    if (fileIndex < files.length) {
        var stat = fs.statSync(path + files[fileIndex]);
        if (stat.isFile()) {
            if (
                files[fileIndex] !== "mimetype" &&
                files[fileIndex] !== ".DS_Store"
            ) {
            archive.file(path + files[fileIndex], { name: files[fileIndex] });
            }
        } else if (stat.isDirectory()) {
            archive.directory(path + files[fileIndex], files[fileIndex]);
        }
        fileAppender(fileIndex + 1);
    } else {
        // finalize the archive (ie we are done appending files but streams have to finish yet)
        // 'close', 'end' or 'finish' may be fired right after calling this method so register to them beforehand
        archive.finalize();
    }
}
fileAppender(0);

我已经测试过设置路径而不是将它们传递到 fileObject 对象中，但我得到了相同的结果。

我是 Nodejs 新手。

Answer 1

问题是由于没有正确处理 promise 造成的。如果我不使用 promise 链而只是将它们作为单独的脚本手动运行，那么一切都会正常。看起来我真的只是需要更加熟悉 Promise。