在GridFS，express，mongoDB，node.js中存储来自POST请求的数据stream
我想弄清楚如何直接将图像发布到GridFS，而不必将其存储在服务器上的任何位置作为临时文件。
我正在使用Postman（chrome ext。）发布文件，并使用以下命令将此文章存储为文件：
req.pipe(fs.createWriteStream('./test.png')); 当从服务器上的文件创buildreadStream时，我也能够从readStream直接存储到GridFS。 （见代码）
我有以下文件， saveFromReq.js监听POST，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);
savePic.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;
任何帮助将不胜感激！
gridfs-stream使得这非常简单：
// `gfs` is a gridfs-stream instance app.post('/picture', function(req, res) { req.pipe(gfs.createWriteStream({ filename: 'test' })); res.send("Success!"); });
而@ robertklep的答案是正确的，我想补充一些他的答案。 这段代码显示了如何发回存储文件的元数据。
app.post('/picture', function(req, res) { req.pipe(gfs.createWriteStream({ filename: 'test' }).on('close', function(savedFile){ console.log('file saved', savedFile); return res.json({file: savedFile}); })); })
这对mongoose工作：
var gfs = Grid(mongoose.connection.db, mongoose.mongo); var writeStream = gfs.createWriteStream({ filename: name, mode: 'w', content_type: 'video/mp4' }); writeStream.on('close', function() { console.log('close event'); }); fs.createReadStream('uploads/' + name + '/' + name + '.mp4').pipe(writeStream); console.log('stream.write: ' + name + '/' + name + '.mp4');
我正在挣扎几天，在客户端浏览器上获取video。 那是我迄今为止所尝试的：
var readstream = gfs.createReadStream({ filename: file.filename }); readstream.on('data', function(data) { res.write(data); console.log(data); }); readstream.on('end', function() { res.end(); }); readstream.on('error', function (err) { console.log('An error occurred!', err); throw err; });
我在MongoDB上的数据看起来像这样：
db.fs.chunks.find（）{“_id”：ObjectId（“5757e76df14741bf0391aaca”），“files_id”：ObjectId（“5757e76df14741bf0391aac8”），“n”：0，“data”：BinData（0，“AAAAIGZ0eXBpc29 .. ..
而contentType是'video / mp4'：
login浏览器端打印这个：
对象{0：“ ”，1：“ ”，2：“ ”，3：“”，4：“f”，5：“t”，6：“y”，7：“p”，8 ：“我”，9：“s”，85003更多…}
有人能救我活吗？ 我希望你不要在这个地方看到我的post不方便。
完整的代码在nodej中使用gridfs在mongodb中插入txtfile
var mongoose=require("mongoose"); var gridfsstream=require("gridfs-stream"); var fs=require("fs"); mongoose.connect("mongodb://localhost:27017/testimage"); var conn=mongoose.connection; gridfsstream.mongo=mongoose.mongo; conn.once("open",function() { console.log("database connected successfully"); var gfs=gridfsstream(conn.db); var writestream=gfs.createWriteStream({ filename:"danger.txt" }); fs.createReadStream("sivakasi.txt").pipe(writestream); writestream.on("close",function(file) { console.log(file.filename +"stored successfully into mongodb using gridfs"); }); writestream.on("error",function(file) { console.log(file.filename +"not stored into mongodb using gridfs"); }); }); conn.on("error",function() { console.log("database not connected try again!!!"); });
完整的代码将图像从html发布到nodejs使用gridfs系统在mongodb中存储该图像，并在服务器中显示该图像。此代码运行良好。
var express=require("express"); var bodyparser=require("body-parser"); var multer=require("multer"); var app=express(); var upload = multer({ dest: '/tmp/'}); app.use(bodyparser.urlencoded({extended:false})); app.post("/uploadimage",upload.single("file"),function(request,response) { var mongoose=require("mongoose"); var gridfsstream=require("gridfs-stream"); var fs=require("fs"); mongoose.connect("mongodb://localhost:27017/testimage"); var con=mongoose.connection; gridfsstream.mongo=mongoose.mongo; con.once("open",function() { console.log("test image database connected successfully"); var gfs=gridfsstream(con.db); var readstream=fs.createReadStream(request.file.originalname); var writestream=gfs.createWriteStream({ filename:"mentorpicthree.jpg" }); readstream.pipe(writestream); writestream.on("close",function() { console.log("image stored in mongodb database successfully"); fs.readFile(request.file.originalname,function(err,data) { if(err) { response.writeHead(404,{"Content-Type":"text/plain"}); console.log("error"); } else { response.writeHead(200,{"Content-Type":"image/jpg"}); response.end(data); } }); }); writestream.on("error",function() { console.log("image not stored in mongodb database"); }); }); con.on("error",function() { console.log("database not connected try again!!!"); }); }); app.listen(8086,function() { console.log("server running on port 8086"); });
<html> <head> <title>FILE UPLOAD</title> </head> <body> <p>Ryan Dhal</p> <form action="http://127.0.0.1:8086/uploadimage" method="POST" enctype="multipart/form-data"> <input type="file" name="file"> <br> <input type="submit" value="UPLOAD"> </form> </body> </html>