[RESOLVED] creating a script to upload image files to the server

trained_monkey

Hello,
I'm designing a script to upload image files to a dynamically created folder on the server and I have a couple of questions: what is the command to create a folder on the server? I'm not sure if 'mkdir' will create the folder on the server or on the user's pc. Also, how would i name the folder so it is unique to each user uploading the files? thanks

dagon

trained_monkey;10927727 wrote:
what is the command to create a folder on the server? I'm not sure if 'mkdir' will create the folder on the server or on the user's pc. Also, how would i name the folder so it is unique to each user uploading the files? thanks

yes its mkdir

you could ask the user to provide a name, or allocate one to them, or if they are already in some sort of log in system use that.

rsmith

Something to keep in mind, PHP is server-side - meaning that any command you issue through a PHP script is carried out on the server, not the users's PC. I agree with Dagon about naming the folder the same as the username. Doing it this way should guarantee no duplication as you would have already ensured the user name to be unique. In fact, as part of the sign-up process, you could pre-create the image directory for that user at registration time. That way, when a user goes to upload, you don't have to ask them anything, their files just upload into their directory.

trained_monkey

The users upload images anonymously, there's no log in process. I want to design a script that will create a folder where the images go. The folder will have to have a unique name for each user uploading the images. I think the simplest way to do this is to append a number to a generic folder name (as in 'user1', 'user2', 'user3'...). The script scans for the largest number and increases it by one then uses it to name the next folder. Is there going to be a problem with this system when there're multiple users accessing the script at the same time?

bretticus

trained_monkey;10927860 wrote:
The users upload images anonymously, there's no log in process. I want to design a script that will create a folder where the images go. The folder will have to have a unique name for each user uploading the images.

That sounds like a contradiction to me. 🙂 But I'm just giving you a hard time. You explain below...

trained_monkey;10927860 wrote:
I think the simplest way to do this is to append a number to a generic folder name (as in 'user1', 'user2', 'user3'...). The script scans for the largest number and increases it by one then uses it to name the next folder.

Are these throwaway folders? I mean why worry about it if the users are anonymous? Unless you need a way to temporarily link the current user to their upload folder in a SESSION???

Do you implement sessions in any way? Why not make a folder with the session id of the current user? If that guid named folder is too ugly for you, you can simply prefix "user" and then create a shorter prettier random number (there are many code examples of creating random strings or numbers. See rand() ) Then just store the new folder name in the user's session.

trained_monkey;10927860 wrote:
Is there going to be a problem with this system when there're multiple users accessing the script at the same time?

If you make a random number as I suggested it shouldn't be an issue. To be more certain, you can use file_exists() to check before you create the new folder.

trained_monkey

bretticus:
Yes, these are temporary folders, after I process the images I will delete them. I guess the only reason I need them to have unique names is so they don't get overwritten and I don't expect them be uploaded more than half a dozen at a time if at all.
Using a combination of rand() and file_exists() will save me from having to parse folder names, that's a good idea.
Do you see any security issues with allowing users to upload files anonymously?

dagon

trained_monkey;10928036 wrote:
Do you see any security issues with allowing users to upload files anonymously?

make sure you check they are images and not any other file type, and if they upload something illegal (child pornography) you could be potential liable.

bretticus

trained_monkey;10928036 wrote:
bretticus:
Yes, these are temporary folders, after I process the images I will delete them. I guess the only reason I need them to have unique names is so they don't get overwritten and I don't expect them be uploaded more than half a dozen at a time if at all.
Using a combination of rand() and file_exists() will save me from having to parse folder names, that's a good idea.

Instead of creating folders then, why not just give the file names random names (random_name.jpg...)? Then you don't have to bother with user folders at all.

trained_monkey

if they upload something illegal (child pornography) you could be potential liable.

LOL....This is not that kind of site, I will be processing those images personally so there won't be a problem with that.

Instead of creating folders then, why not just give the file names random names

Because I have to sort out those images, it will be easier for me if they were in seperate folders

I have a pretty good idea of what i need to do now, thank you all very much

dagon

trained_monkey;10928052 wrote:
LOL....This is not that kind of site, I will be processing those images personally so there won't be a problem with that.

its not about what kind of site it is, when you allow strangers to upload images without control things like that happen.