Howto: Create and Stream a CSV with PHP
I find myself constantly creating csv files for users to download. Whether it’s a method for users to export their data to excel, a way for users to backup their hosted data, or just a simple way to send them report information, csv files are extremely useful. Normally I just create an actual file and link to it for the user to download. The files are usually cleaned up after a certain amount of time or after a certain number of newer files exist.
Recently however, I had a client that really wanted to be able to export data in csv format without ever creating a file on the webserver. Their concern was rooted in security, but the reality of the matter was that they were trying to obey the letter of the law with regards to company policies. Whether it was truly necessary or not is for another discussion. Instead, the technique is actually very useful so I thought I’d share.
The key to this is that the fopen function supports php input/output streams as wrappers.
