Check if a file exists in Rails

Recently I was porting a legacy PHP application to Rails. One of the primary tasks was to resize a bunch of images. Below you can see what one of the database rows looks like.

mysql> SELECT id, filename FROM old_posts
+----+---------------------------------------+
| id | filename                              |
+----+---------------------------------------+
|  1 | unxplained-photo-1225258423-85706.jpg |
+----+---------------------------------------+
1 row in set (0.00 sec)                                                                  

mysql>

You’ll see that the name of the filename is stored in the database, the problem I encountered was that often times the actual file didn’t exist even though the record remained in the database.

Rails would get angry at me when I tried to resize an non-existent file. To account for this, I did the following:

if FileTest.exists?(filename)
 # some code here to
 # resize the image
end

For more information on this handy ruby module pop into the docs.

This entry was posted on Saturday, February 21st, 2009 at 4:15 pm and is filed under ruby on rails. You can follow any comments to this entry through the RSS 2.0 feed. You can leave a comment, or trackback from your own site.

3 comments

  1. alex grande
    May 18, 2009 at 8:01 pm

    I bet I should use this like <div class=”clear”></div>. All over the place!

  2. ajay
    May 22, 2009 at 7:15 am

    thanks a lot.. i had written a function to do the same thing…but when you so beautifully described it in a line.. take care.. cheers !

  3. Ruby on rails
    March 3, 2010 at 4:18 am

    hmmm its usefull info of ruby on rails

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