Best practice to load video from filesystem API

Question

I am just researching and playing around with HTML5 FileSystem API. I am downloading a video from the server and saving it to the local sandbox filesystem. Say a user comes to the sites, hits download on the video, it saves to the filesystem, then the user happens to go offline. My question is, what is the best practice for checking if video is already in the filesystem and loading it from there?

Thanks

Answer 1

You're asking about persistent, client-side storage of video, specifically using the Directories and System API, sometimes called "File System API." I believe this is currently only supported on Chrome 28 and Opera 16 or higher – i.e., slightly less than 1 in 3 web users right now.

Per the API spec, the users will be prompted to allow the quota for the on-client storage allotment because you're requesting persistent, not transient, storage. While the persistent client storage may be handy, it's not entirely transparent to the user.

As for determining if the Chrome or Opera user has the video stored locally, simply calling getFile() file will do it; if the file doesn't exist, it simply throws an error that you can then handle to go ahead and pull down the video. That's the standard / best practice way of determining if a file has been stored locally.

PS: Yes, I see that Blackberry mobile supports the API, too. I just don't know if either of the remaining Blackberry users will have the device storage quota available for video :-)