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htmlhtml5-filesystem

Html5 Filesystem API accessing lost url files

I used the filesystem api to create an image analysis app.

I ran this application off of amazon EC2 and uploaded a large number of images.

After rebooting the EC2 instance the public DNS changed and I lost access to my images.

Since the files exist on my computer I am trying to figure out how I could retrieve them for the new DNS. Visiting the physical directory only gives me a lot of obscurely named files.

If I could compile these files into their filesystem api format I could just upload them again, but I'm not sure how to do that.

Effectively I would like to change the origin for a set of filesystem api files.

enter image description here

If I could change origin for that File System to the new ec2 instance origin I would be set.

Solution

  • HTML5 File System API stores files locally see locations here. This directory looks like:

    File System Directory

    Each of the 001,002,etc. directories map to a unique filesystem path (i.e. filesystem:http://example.com/persistent/). So to change the origin of a file system we simply need to rename the directory.

    In my case:

    1. 004 directory mapped to my old EC2 Instance DNS.
    2. 011 directory mapped to new EC2 Instance DNS.

    So I just replaced the contents of 011 with the contents of 004.

    One final caveat.
    Any file in a file system directory (like image files) that reference a path will use the filesystem:http... path associated with the old file system. All of these paths need to be renamed.

    Unfortunately this method won't allow you to merge two file systems, doing so would require editing binary files located in ###/p/Paths and probably be tough.