我想找出如何直接将图像发布到GridFS,而不需要先将它作为临时文件存储在服务器上。
我正在使用Postman(Chrome扩展程序)来发布文件,我设法使用以下命令将此提交的内容存储为文件:
req.pipe(fs.createWriteStream('./test.png'));
当从服务器上的文件创建readStream时,我还可以直接将其存储到GridFS中(请参见代码)。
我有以下文件:saveFromReq.js
监听POST请求,基本上只是将其传递给savePic.js
。
saveFromReq.js
:
var express = require('express');
var app = express();
var savePic = require('./savePic');
var fs = require('fs');
var GridStore = require('mongodb').GridStore;
var pic = './square.png';
var picID;
//When the following
//var pic = fs.createReadStream('./square.png', {autoClose: true});
//is not commented out, and 'req' is replaced with 'pic' in the savePic function,
//the file square.png is stored correctly to GridFS
app.post('/picture', function(req, res){
savePic(req, function(id){});
res.writeHead(200, {'Content-Type': 'text' });
res.end("Sucsess!\n");
});
app.listen(process.env.PORT || 3413);
保存图片.js:
var savePic = function(req, callback){
var Db = require('mongodb').Db,
MongoClient = require('mongodb').MongoClient,
Server = require('mongodb').Server,
ReplSetServers = require('mongodb').ReplSetServers,
ObjectID = require('mongodb').ObjectID,
Binary = require('mongodb').Binary,
GridStore = require('mongodb').GridStore,
Grid = require('mongodb').Grid,
Code = require('mongodb').Code,
BSON = require('mongodb').pure().BSON,
assert = require('assert');
fs = require('fs');
//When the following
//req.pipe(fs.createWriteStream('./test.png'));
//is not commented out, the correct image is stored to test.png, and
//the sequence after req.on("data"... starts
//(That sequence does not start at all when this is commented out..)
var fileId = new ObjectID();
var db = new Db('testDB', new Server('localhost', 27017));
// Establish connection to db
db.open(function(err, db) {
var gridStore = new GridStore(db, 'test', 'w');
//open
gridStore.open(function(err, gridStore) {
console.log("opened");
req.on("data", function (data) {
console.log("data recieved");
gridStore.write(data, function (err, gridStore) {
if (err) {
console.log("error writing file");
}
});
});
req.on("end", function () {
gridStore.close(function (err, gridStore) {
if (!err) {
console.log("The file has been stored to database.");
db.close();
}
});
});
req.pipe(gridStore);
});
});
callback(fileId);
};
module.exports = savePic;
任何帮助都将不胜感激!