Download large file in php with time limit - php

I'm trying to create a simple script which takes a URL in a form, download the file and deliver that file to the user. Something like a proxy server, only for downloading files. The only problem is that the server has limited execution time of 10 seconds which will fail for most large files. I can't change the execution time (using set_time_limit) because that's blocked too. Is there ANY way I can get past this?

you can use an cloud storage service to store the file for you
google drive api
dropbox-php
to "deliver" the file to the user you share the link on your cloud storage service.
Ps: Sorry for the previous wrong answer, ftp_get only works if you are trying tpo get it from an ftp server

Get a new web host, a cheap one that I can recommend is Dreamhost which is pretty darn cheap and they have a lot of PHP ini settings you can override (but not all). Or, if you're just playing around and are looking for something temporary, I recommend AWS EC2, the micro instance is as cheap as $0.02/hour depending on the region you select and you get 1 month for free, but most importantly, you get FULL root access.
Edit:
Forgot to mention where to view override PHP settings info: wiki.dreamhost.com/index.php/PHP.ini
(sorry I can't make it a link, I'm a n00b on stackoverflow and am limited to 2 links)

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Inter-network File Transfers using PHP with polling

I am designing a web-based file-managment system that can be conceptualised as 3 different servers:
The server that hosts the system interface (built in PHP) where users 'upload' and manage files (no actual files are stored here, it's all meta).
A separate staging server where files are placed to be worked on.
A file-store where the files are stored when they are not being worked on.
All 3 servers will be *nix-based on the same internal network. Users, based in Windows, will use a web interface to create an initial entry for a file on Server 1. This file will be 'uploaded' to Server 3 either from the user's local drive (if the file doesn't currently exist anywhere on the network) or another network drive on the internal network.
My question relates to the best programmatic approach to achieve what I want to do, namely:
When a user uploads a file (selecting the source via a web form) from the network, the file is transferred to Server 3 as an inter-network transfer, rather than passing through the user (which I believe is what would happen if it was sent as a standard HTTP form upload). I know I could set up FTP servers on each machine and attempt to FXP files between locations, but is this preferable to PHP executing a command on Server 1 (which will have global network access), to perform a cross-network transfer that way?
The second problem is that these are very large files we're talking about, at least a gigabyte or two each, and so transfers will not be instant. I need some method of polling the status of the transfer, and returning this to the web interface so that the user knows what is going on.
Alternatively this upload could be left to run asyncrhonously to the user's current view, but I would still need a method to check the status of the transfer to ensure it completes.
So, if using an FXP solution, how could polling be achieved? If using a file move/copy command from the shell, is any form of polling possible? PHP/JQuery solutions would be very acceptable.
My final part to this question relates to windows network drive mapping. A user may map a drive (and select a file from), an arbitrarily specified mapped drive. Their G:\ may relate to \server4\some\location\therein, but presumably any drive path given to the server via a web form will only send the G:\ file path. Is there a way to determine the 'real path' of mapped network drives?
Any solution would be used to stage files from Server 3 to Server 2 when the files are being worked on - the emphasis being on these giant files not having to pass through the user's local machine first.
Please let me know if you have comments and I will try to make this question more coherant if it is unclear.
As far as I’m aware (and I could be wrong) there is no standard way to determine the UNC path of a mapped drive from a browser.
The only way to do this would be to have some kind of control within the web page. Could be ActiveX or maybe flash. I’ve seen ActiveX doing this, but not flash.
In the past when designing web based systems that need to know the UNC path of a user’s mapped drive I’ve had to have a translation of drive to UNC path stored server side. I did have a luxury though of knowing which drive would map to what UNC path. If the user can set arbitrary paths then this obviously won’t work.
Ok, as I’m procrastinating and avoiding real work I’ve given this some thought.
I’ll preface this by saying that I’m in no way a Linux expert and the system I’m about to describe has just been thought up off the top of my head and is not something you’d want to put into any kind of production. However, it might help you down the right path.
So, you have 3 servers, the Interface Server (LAMP stack I’m assuming?) your Staging Server and your File Store Server. You will also have Client Machines and Network Shares. For the purpose of this design your Network Shares are hosted on nix boxes that your File Store can scp from.
You’d create your frontend website that tracks and stores information about files etc. This will also hold the details about which files are being copied, which are in Staging and so on.
You’ll also need some kind of Service running on the File Store Server. I’ll call this the File Copy Service. This will be responsible for coping the files from your servers hosting the network shares.
Now, you’ve still got an issue with how you figure out what path the users file is actually on. If you can stop users from mapping their own drives and force them to use consistent drive letters then you could keep a translation of drive letter to UNC path on the server. If you can’t, well I’ll let you figure that out. If you’re in a windows domain you can force the drive mappings using Group Policies.
Anyway, the process for the system would work something like this.
User goes to system and selects a file
The Interface server take the file path and calls the File Copy Service on the File Store Server
The File Copy Service connects to the server that hosts the file and initiates the copy. If they’re all nix boxes you could easily use something like SCP. Now, I haven’t actually looked up how to do it but I’d be very surprised if you can’t get a running total of percentage complete from SCP as it’s copying. With this running total the File Copy Service will be updating the database on the Interface Server with how the copy is doing so the user can see this from the Interface Server.
The File Copy Service can also be used to move files from the File Store to the staging server.
As i said very roughly thought out. The above would work, but it all depends a lot on how your systems are set up etc.
Having said all that though, there must be software that would do this out there. Have you looked?
If iam right is this archtecture:
Entlarge image
1.)
First lets sove the issue of "inter server transfer"
I would solve this issue by mount the FileSystem from Server 2 and 3 to Server 1 by NFS.
https://help.ubuntu.com/8.04/serverguide/network-file-system.html
So PHP can direct store files on file system and dont need to know on which server the files realy is.
/etc/exports
of Server 2 + 3
/directory/with/files 192.168.IPofServer.1 (rw,sync)
exportfs -ra
/etc/fstab
of Server 1
192.168.IPofServer.2:/var/lib/data/server2/ /directory/with/files nfs rsize=8192,wsize=8192,timeo=14,intr
192.168.IPofServer.3:/var/lib/data/server3/ /directory/with/files nfs rsize=8192,wsize=8192,timeo=14,intr
mount -a
2.)
Get upload progress for realy large files,
here are some possibilitys to have a progress bar for http uploads.
But for a resume function you would have to use a flash plugin.
http://fineuploader.com/#demo
https://github.com/valums/file-uploader
or you can build it by your selfe using the apc extension
http://www.amwsites.com/blog/2011/01/use-a-combination-of-jquery-php-apc-uploadprogress-to-show-progress-bar-during-an-upload/
3.)
Lets Server load files from Network drive.
This i would try with a java applet to figurre out the real network path and send this to server, so the server can fetch the file in background.
But i never didt thinks like this before and have no further informations.

Keep Uploaded Files in Sync Across Multiple Servers - PHP Linux

I have a website right now that is currently utilizing 2 servers, a application server and a database server, however the load on the application server is increasing so we are going to add a second application server.
The problem I have is that the website has users upload files to the server. How do I get the uploaded files on both of the servers?
I do not want to store images directly in a database as our application is database intensive already.
Is there a way to sync the servers across each other or is there something else I can do?
Any help would be appreciated.
Thanks
EDIT: I am adding the following links for people that helped me understand this question more:
Synchronize Files on Multiple Servers
and
Keep Uploaded Files in Sync Across Multiple Servers - LAMP
For all Reading this post NFS seems to be the better of the 2.
NFS will keep files in sync but you could also use ftp to upload the files across all servers as well but NFS looks like the way to go.
This is a question for serverfault.
Anyway I think you should definitely consider getting in the "cloud".
Syncing uploads from one server to another is simply unreliable - you have no idea what kind of errors you can get and why you can get them. Also the syncing process will load both servers. For me the proper solution is going in the cloud.
Should you chose the syncing method you have a couple of solutions:
Use rsync to sync the files you need between the servers.
Use crontab to sync the files every X minutes/hours/days.
Copy the files upon some event (user login etc)
I got this answer from server fault:
The most appropriate course of action in a situation like this is to break the file share into a separate service of its own. Don't duplicate files if you have a network that can let the files be "everywhere (almost) at once." You can do this through NFS/CIFS or through a proper storage protocol like iSCSI. Mount as local storage in the appropriate directory. Depending on the performance of your network and your storage needs, this could add a couple of undetectable milliseconds to page load time.
So using NFS to share server files would work OR
as stated by #kgb you could specify one single server to hold all uploaded files and have other servers pull from that (just make sure you run a cron or something to back up the file)
Most sites solve this problem by using a 3rd party designated file server like Amazon S3 for the user uploads.
Another answer could be to use a piece of software called BTSync, it is very easy to install and use and could allow you to easily keep files in sync accross as many servers as you need to. It takes only 3 terminal commands to install and is very efficient.
Take a look here
and here
You can use db server for storage... Not in the db i mean, have a web server running there too. It is not going to increase cpu load much, but is going to require a better channel.
you could do it with rsync.. people have suggested using nfs.. but that way you create one point of failure... if the nfs server goes down.. both your servers are screwed... correct me if im wrong

Splitting form submissions to speed up transfer time

I have a simple CRM system that allows sales to put in customer info and upload appropriate files to create a project.
The system is already being hosted in the cloud. But the office internet upload speed is horrendous. One file may take up to 15 minutes or more to finish, causing a bottleneck in the sales process.
Upgrading our office internet is not an option; what other good solutions are out there?
I propose splitting the project submission form into 2 parts. Project info fields are posted directly to our cloud server webapp and stored in the appropriate DB table, the file submission will actually be submitted to a LAN server with a simple DB and api that will allow the cloud-hosted server webapp to communicate with to retrieve the file if ever needed again via a download link. Details need to be worked out for this set-up. But this is what I want to do in general.
Is this a good approach to solving this slow upload problem? I've never done this before, so are there also any obstacles to this implementation (cross-domain restrictions is something that comes into mind, but I believe that can be fixed with using an iFrame)?
If bandwidth is the bottleneck, then you need a solution that doesn't chew up all your bandwidth. You mentioned that you can't upgrade your bandwidth - what about putting in a second connection?
If not, the files need to stay on the LAN a little longer. It sounds like your plan would be to keep the files on the LAN forever, but you can store them locally initially and then push them later.
When you do copy the files out to the cloud, be sure to compress them and also setup rate limiting (so they take up maybe 10% of your available bandwidth during business hours).
Also put some monitoring in place to make sure the files are being sent in a timely manner.
I hope nobody needs to download those files! :(

Input on decision: file hosting with amazon s3 or similar and php

I appreciate your comments to help me decide on the following.
My requirements:
I have a site hosted on a shared server and I'm going to provide content to my users. About 60 GB of content (about 2000 files 30mb each. Users will have access to only 20 files at a time), I calculate about 100 GB monthly bandwidth usage.
Once a user registers for the content, links will be accessible for the user to download. But I want the links to expire in 7 days, with the posibility to increase the expiration time.
I think that the disk space and bandwidth calls for a service like Amazon S3 or Rackspace Cloud files (or is there an alternative? )
To manage the expiration I plan to somehow obtain links that expire (I think S3 has that feature, not Rackspace) OR control the expiration date on my database and have a batch process that will rename on a daily basis all 200 files on the cloud and on my database (in case a user copied the direct link, it won't work the next day, only my webpage will have the updated links). PHP is used for programming.
So what do you think? Cloud file hosting is the way to go? Which one? Does managing the links makes sense that way or it is too difficult to do that through programming (send commands to the cloud server...)
EDIT:
Some host companies have Unlimited space and Bandwidth on their shared plans.. I asked their support staff and they said that they really honor the "unlimited" deal. So 100 GB of transfer a month is ok, the only thing to look out is CPU usage. So going shared hosting is one more alternative to choose from..
FOLLOWUP:
So digging more into this I found that the TOS of the Unlimited plans say that it is not permitted to use the space primarily to host multimedia files. So I decided to go with Amazon s3 and the solution provided by Tom Andersen.
Thanks for the input.
I personally don't think you necessarily need to go to a cloud based solution for this. It may be a little costly. You could simply get a dedicated server instead. One provider that comes to mind gives 3,000 GB/month of bandwidth on some of their lowest level plans. That is on a 10Mbit uplink; you can upgrade to 100Mbps for $10/mo of 1Gbit for $20/mo. I won't mention any names, but you can search for dedicated servers and possibly find one to your liking.
As for expiring the files, just implement that in PHP backed by a database. You won't have to move files around, store all the files in a directory not accessible from the web, and use a PHP script to determine if the link is valid, and if so read the contents of the file and pass them through to the browser. If the link is invalid, you can show an error message instead. It's a pretty simple concept and I think there are a lot of pre-written scripts that do that available, but depending on your needs, it isn't too difficult to do it yourself.
Cloud hosting has advantages, but right now I think its costly and if you aren't trying to spread the load geographically or plan on supporting thousands of simultaneous users and need the elasticity of the cloud, you could possibly use a dedicated server instead.
Hope that helps.
I can't speak for S3 but I use Rackspace Cloud files and servers.
It's good in that you don't pay for incoming bandwidth, so uploads are super cheap.
I would do it like this:
Upload all the files you need to a 'private' container
Create a public container with CDN enabled
That'll give you a special url like http://c3214146.r65.ce3.rackcdn.com
Make your own CNAME DNS record for your domain point to that, like: http://cdn.yourdomain.com
When a user requests a file, use the COPY api operation with a long random filename to do a server side copy from the private container to the public container.
Store the filename in a mysql DB for your app
Once the file expires, use the DELETE api operation, then the PURGE api operation to get it out of the CDN .. finally delete the record from the mysql table.
With the PURGE command .. I heard it doesn't work 100% of the time and it may leave the file around for an extra day .. also in the docs it says to reserve it's use for only emergency things.
Edit: I just heard, there's a 25 purge per day limit.
However personally I've just used delete on objects and found that took it out the CDN straight away. In summary, the worst case would be that the file would still be accessible on some CDN nodes for 24 hours after deletion.
Edit: You can change the TTL (caching time) on the CDN nodes .. default is 72 hours so might pay to set it to something lower .. but not so low that you loose the advantage of CDN.
The advantages I find with the CDN are:
It pushes content right out to end users far away from the USA servers and gives super fast download times for them
If you have a super popular file .. it won't take out your site when 1000 people start trying to download it .. as they'd all get copies pushed out the whatever CDN node they were closest to.
You don't have to rename the files on S3 every day. Just make them private (which is default), and hand out time limited urls for day or a week to anyone who is authorized.
I would consider making the links only good for 20 mins, so that a user has to re-login in order to re-download the files. Then they can't even share the links they get from you.

Will I run into load problems with this application stack?

I am designing a file download network.
The ultimate goal is to have an API that lets you directly upload a file to a storage server (no gateway or something). The file is then stored and referenced in a database.
When the file is requsted a server that currently holds the file is selected from the database and a http redirect is done (or an API gives the currently valid direct URL).
Background jobs take care of desired replication of the file for durability/scaling purposes.
Background jobs also move files around to ensure even workload on the servers regarding disk and bandwidth usage.
There is no Raid or something at any point. Every drive ist just hung into the server as JBOD. All the replication is at application level. If one server breaks down it is just marked as broken in the database and the background jobs take care of replication from healthy sources until the desired redundancy is reached again.
The system also needs accurate stats for monitoring / balancing and maby later billing.
So I thought about the following setup.
The environment is a classic Ubuntu, Apache2, PHP, MySql LAMP stack.
An url that hits the currently storage server is generated by the API (thats no problem far. Just a classic PHP website and MySQL Database)
Now it gets interesting...
The Storage server runs Apache2 and a PHP script catches the request. URL parameters (secure token hash) are validated. IP, Timestamp and filename are validated so the request is authorized. (No database connection required, just a PHP script that knows a secret token).
The PHP script sets the file hader to use apache2 mod_xsendfile
Apache delivers the file passed by mod_xsendfile and is configured to have the access log piped to another PHP script
Apache runs mod_logio and an access log is in Combined I/O log format but additionally estended with the %D variable (The time taken to serve the request, in microseconds.) to calculate the transfer speed spot bottlenecks int he network and stuff.
The piped access log then goes to a PHP script that parses the url (first folder is a "bucked" just as google storage or amazon s3 that is assigned one client. So the client is known) counts input/output traffic and increases database fields. For performance reasons i thought about having daily fields, and updating them like traffic = traffic+X and if no row has been updated create it.
I have to mention that the server will be low budget servers with massive strage.
The can have a close look at the intended setup in this thread on serverfault.
The key data is that the systems will have Gigabit throughput (maxed out 24/7) and the fiel requests will be rather large (so no images or loads of small files that produce high load by lots of log lines and requests). Maby on average 500MB or something!
The currently planned setup runs on a cheap consumer mainboard (asus), 2 GB DDR3 RAM and a AMD Athlon II X2 220, 2x 2.80GHz tray cpu.
Of course download managers and range requests will be an issue, but I think the average size of an access will be around at least 50 megs or so.
So my questions are:
Do I have any sever bottleneck in this flow? Can you spot any problems?
Am I right in assuming that mysql_affected_rows() can be directly read from the last request and does not do another request to the mysql server?
Do you think the system with the specs given above can handle this? If not, how could I improve? I think the first bottleneck would be the CPU wouldnt it?
What do you think about it? Do you have any suggestions for improvement? Maby something completely different? I thought about using Lighttpd and the mod_secdownload module. Unfortunately it cant check IP adress and I am not so flexible. It would have the advantage that the download validation would not need a php process to fire. But as it only runs short and doesnt read and output the data itself i think this is ok. Do you? I once did download using lighttpd on old throwaway pcs and the performance was awesome. I also thought about using nginx, but I have no experience with that. But
What do you think ab out the piped logging to a script that directly updates the database? Should I rather write requests to a job queue and update them in the database in a 2nd process that can handle delays? Or not do it at all but parse the log files at night? My thought that i would like to have it as real time as possible and dont have accumulated data somehwere else than in the central database. I also don't want to keep track on jobs running on all the servers. This could be a mess to maintain. There should be a simple unit test that generates a secured link, downlads it and checks whether everything worked and the logging has taken place.
Any further suggestions? I am happy for any input you may have!
I am also planning to open soure all of this. I just think there needs to be an open source alternative to the expensive storage services as amazon s3 that is oriented on file downloads.
I really searched a lot but didnt find anything like this out there that. Of course I would re use an existing solution. Preferrably open source. Do you know of anything like that?
MogileFS, http://code.google.com/p/mogilefs/ -- this is almost exactly thing, that you want.

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