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我一直在用 Node.js 编写一个应用程序，它将图像存储在 MongoDB 的 GridFS 文件系统中。

我已经通过该应用上传了图像，并且图像似乎已正确存储：

$ mongofiles -v -d speaker-karaoke get howard-basement-100x115.jpg
Tue Jul 17 12:14:16 creating new connection to:127.0.0.1
Tue Jul 17 12:14:16 BackgroundJob starting: ConnectBG
Tue Jul 17 12:14:16 connected connection!
connected to: 127.0.0.1
done write to: howard-basement-100x115.jpg

这从 MongoDB 中抓取了 .jpg，我可以毫无问题地打开它，所以看起来我上传的内容被正确存储。

但是，在我正在运行的应用程序中，当我尝试读取同一个文件时，我得到：

12:15:44 web.1     | started with pid 89621
12:15:45 web.1     | Connecting to mongodb://localhost/speaker-karaoke
12:15:45 web.1     | Speaker Karaoke express app started on 5000
12:15:48 web.1     | DEBUG: Get review thumbnail for 5005b7550333650000000001
12:15:48 web.1     | 
12:15:48 web.1     | node.js:201
12:15:48 web.1     |         throw e; // process.nextTick error, or 'error' event on first tick
12:15:48 web.1     |               ^
12:15:48 web.1     | Error: Illegal chunk format
12:15:48 web.1     |     at Error (unknown source)
12:15:48 web.1     |     at new <anonymous> (/Users/hlship/workspaces/github/speaker-karaoke/node_modules/mongodb/lib/mongodb/gridfs/chunk.js:43:11)
12:15:48 web.1     |     at /Users/hlship/workspaces/github/speaker-karaoke/node_modules/mongodb/lib/mongodb/gridfs/gridstore.js:488:24
12:15:48 web.1     |     at Cursor.nextObject (/Users/hlship/workspaces/github/speaker-karaoke/node_modules/mongoose/node_modules/mongodb/lib/mongodb/cursor.js:462:5)
12:15:48 web.1     |     at [object Object].<anonymous> (/Users/hlship/workspaces/github/speaker-karaoke/node_modules/mongoose/node_modules/mongodb/lib/mongodb/cursor.js:456:12)
12:15:48 web.1     |     at [object Object].g (events.js:156:14)
12:15:48 web.1     |     at [object Object].emit (events.js:88:20)
12:15:48 web.1     |     at Db._callHandler (/Users/hlship/workspaces/github/speaker-karaoke/node_modules/mongoose/node_modules/mongodb/lib/mongodb/db.js:1290:25)
12:15:48 web.1     |     at /Users/hlship/workspaces/github/speaker-karaoke/node_modules/mongoose/node_modules/mongodb/lib/mongodb/connection/server.js:329:30
12:15:48 web.1     |     at [object Object].parseBody (/Users/hlship/workspaces/github/speaker-karaoke/node_modules/mongoose/node_modules/mongodb/lib/mongodb/responses/mongo_reply.js:118:5)
12:15:48 web.1     | process terminated
12:15:48 system    | sending SIGTERM to all processes

使用此代码（CoffeeScript，用于 Express）：

  app.get "/images/review-thumbnail/:id", (req, res) ->

    id = req.params.id

    util.debug "Get review thumbnail for #{id}"

    store = new GridStore mongoose.connection.db, new ObjectID(id), null, "r"

    store.open (err, file) ->

      throw err if err

      util.debug "Store open for #{id}, type = #{file.contentType}"

      # TODO: Scale the image before sending it!

      res.header "Content-Type", file.contentType

      store.stream(true).pipe res

所以它似乎甚至没有将它传递给传递给 store.open() 的回调。

当您知道 id 但不知道文件名时，打开 GridFS 文件是否有问题？

顺便提一句：

$ npm ls
speaker-karaoki@0.0.1 /Users/hlship/workspaces/github/speaker-karaoke
├─┬ blueimp-file-upload-node@1.0.2  extraneous
│ ├── formidable@1.0.11 
│ ├── imagemagick@0.1.2 
│ └── node-static@0.6.0 
├── coffee-script@1.3.3 
├─┬ connect-assets@2.1.9 
│ ├── connect-file-cache@0.2.4 
│ ├── mime@1.2.2 
│ ├─┬ snockets@1.3.4 
│ │ ├── coffee-script@1.3.3 
│ │ ├── dep-graph@1.0.1 
│ │ └── uglify-js@1.0.7 
│ └── underscore@1.1.7 
├─┬ express@2.5.9 
│ ├─┬ connect@1.9.1 
│ │ └── formidable@1.0.11 
│ ├── mime@1.2.4 
│ ├── mkdirp@0.3.0 
│ └── qs@0.4.2 
├─┬ jade@0.26.0 
│ ├── commander@0.5.2 
│ └── mkdirp@0.3.0 
├─┬ mongodb@1.0.2 
│ └── bson@0.0.6 
├─┬ mongoose@2.7.0 
│ ├── hooks@0.2.1 
│ └─┬ mongodb@1.0.2 
│   └── bson@0.0.6 
├─┬ passport@0.1.10 
│ └── pkginfo@0.2.3 
├─┬ passport-twitter@0.1.3 
│ ├─┬ passport-oauth@0.1.9 
│ │ ├── oauth@0.9.7 
│ │ └── passport@0.1.11 
│ └── pkginfo@0.2.3 
├── sass@0.5.0 
└── underscore@1.3.3

这是它失败的功能：

var Chunk = exports.Chunk = function(file, mongoObject) {
  if(!(this instanceof Chunk)) return new Chunk(file, mongoObject);

  this.file = file;
  var self = this;
  var mongoObjectFinal = mongoObject == null ? {} : mongoObject;

  this.objectId = mongoObjectFinal._id == null ? new ObjectID() : mongoObjectFinal._id;
  this.chunkNumber = mongoObjectFinal.n == null ? 0 : mongoObjectFinal.n;
  this.data = new Binary();

  if(mongoObjectFinal.data == null) {
  } else if(typeof mongoObjectFinal.data == "string") {
    var buffer = new Buffer(mongoObjectFinal.data.length);
    buffer.write(mongoObjectFinal.data, 'binary', 0);
    this.data = new Binary(buffer);
  } else if(Array.isArray(mongoObjectFinal.data)) {
    var buffer = new Buffer(mongoObjectFinal.data.length);
    buffer.write(mongoObjectFinal.data.join(''), 'binary', 0);
    this.data = new Binary(buffer);
  } else if(mongoObjectFinal.data instanceof Binary || Object.prototype.toString.call(mongoObjectFinal.data) == "[object Binary]") {    
    this.data = mongoObjectFinal.data;
  } else if(Buffer.isBuffer(mongoObjectFinal.data)) {
  } else {
    throw Error("Illegal chunk format");
  }
  // Update position
  this.internalPosition = 0;
};

解决方案

在此处更新解决方案，因为它在下面的评论中未正确呈现。

问题是重复；有两个副本，即使版本相同，也是 mongodb 和 bson。

幸运的是，mongoose 将它所需的 mongodb 导出为属性 mongo，因此我能够从我的文件中删除显式 mongodbpackage.json并进行了更改：

mongo = require "mongodb"
mongoose = require "mongoose"

至：

mongoose = require "mongoose"
mongo = mongoose.mongo

事情现在看起来不错；我仍然认为模块系统需要一种认可的方式来访问依赖项依赖项（对于一个 dep 不够周到暴露其 deps 的情况）。

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1 回答 1

2

很确定它是 mongodb 模块的重复副本（相同版本）；删除 node_modules 和 nmp install 似乎已经修复了它。

于 2012-07-18T00:20:28.507 回答