在Trevor Turk的博客文章"Easy Upload via URL with Paperclip"中成功实施了几次代码后，在最新的迭代中，我的应用程序给了我以下错误：
Started POST "/pins" for 127.0.0.1 at 2013-02-22 14:05:20 -0300
Processing by PinsController#create as HTML
Parameters: {"utf8"=>"✓", "authenticity_token"=>"Q6kmHS7Co+j2Y4JYd+3YO0OmDHU/upK1ADvRbS8UAIc=", "pin"=>{"image_url"=>"http://media-cache-ec3.pinterest.com/550x/b4/b7/82/b4b782bf268cb52d201853886510e3a9.jpg", "description"=>"Test"}, "commit"=>"Create Pin"}
[1m[36mUser Load (0.2ms)[0m [1mSELECT "users".* FROM "users" WHERE "users"."id" = 1 LIMIT 1[0m
[1m[35m (0.1ms)[0m begin transaction
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-c7vstl'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-17pzds5'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1kh7v9y'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-ngtq1u'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-jzmkac'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1x4vpj5'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1iwdp4q'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-cvro9z'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1tn727x'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-q77ipe'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1e5wt1x'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-7xaoic'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-kzw7ab'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-m1frw1'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-aojdb8'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-kzn0w6'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-cj55fi'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-d3s1h0'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-15hmo2q'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-17apjuj'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-f97eej'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1t9ou1f'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1dfnz21'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-ozc0ac'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1uiz51r'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-57ahli'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-u96rmb'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-vt2ph3'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-st55ih'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1phbyb3'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-wdu3nu'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1iit16u'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-117n6l2'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-qr5380'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-tod0l9'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1u19f33'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1rta45x'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-6o0hug'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-14e2zh7'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1lnwdhm'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-9en3jt'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-hhb0b2'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-9b0ak8'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1yyvnl9'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-15ebo0r'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-kpavxm'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-qgrtq2'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1erqxe5'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1h23wb0'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1heb0b3'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1oswpj8'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1y1z7di'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-89spzg'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-96op3f'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-4aizhy'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1s5nw68'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-k4jb2y'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1gjqddi'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1nzej79'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1yurmzq'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1yvoyxn'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-ec4b0b'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-12zau9q'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-va8ryp'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-11362zg'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-14d0lek'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-65t94r'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-2zqkrs'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-nzvtnc'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-mokk7l'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1v6n3k3'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-7tvcwq'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-z4qieu'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-5let78'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1azr7s1'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-xfbbhj'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-qpuxih'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1oqv313'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1lw2iyw'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-sgsyl7'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-z3kc9d'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1csf869'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1615j19'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-gjlms9'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1t0vhjc'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1x2w35'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1wgmxox'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-ce9qo7'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1mxr8v0'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1y1716x'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-19vj2ky'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1s2yq7p'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-10xd3y3'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-fohqek'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1p8i5y4'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-mx211u'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-nhtv6r'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1sdvwt9'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1nu8xde'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1yo03yt'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-pfu1cg'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-oqslme'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1s8wcup'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1x91fzc'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1b3zxzf'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1miary7'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-18ef2u'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-eo8odm'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1noqove'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-hl4yhz'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-mqjd16'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-10do8b2'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-n1dqn2'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1raiaq5'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1myor64'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1i2e0b3'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-hgtnym'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-lzuyqt'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-1cvazmm'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-shgn3h'
Command :: file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-a1n19w'
[1m[36m (0.1ms)[0m [1mrollback transaction[0m
Completed 500 Internal Server Error in 201007ms
Errno::EMFILE (Too many open files - file -b --mime '/var/folders/8z/sh44jtbs33163s5hsjxj6tsc0000gr/T/open-uri20130222-25293-a1n19w'):
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/models/pin.rb:27:in `download_remote_image'
app/controllers/pins_controller.rb:48:in `block in create'
app/controllers/pins_controller.rb:47:in `create'
看起来发生了某种无限递归，虽然我无法弄清楚在哪里。
以下是相关模型的样子：
require 'open-uri'
class Pin < ActiveRecord::Base
belongs_to :user
attr_accessible :description, :image, :image_url
has_attached_file :image, styles: { medium: "320x240>"}
validates :description, presence: true
validates :user_id, presence: true
validates_attachment :image, presence: true,
content_type: { content_type: ['image/jpeg', 'image/jpg', 'image/png', 'image/gif'] },
size: { less_than: 5.megabytes }
# Remote image downloading
attr_accessor :image_url
before_validation :download_remote_image, :if => :image_url_provided?
private
def image_url_provided?
!self.image_url.blank?
end
def download_remote_image
self.image = URI.parse(image_url)
# self.image_remote_url = image_url
end
def do_download_remote_image
io = open(URI.parse(image_url))
def io.original_filename; base_uri.path.split('/').last; end
io.original_filename.blank? ? nil : io
rescue # catch url errors with validations instead of exceptions (Errno::ENOENT, OpenURI::HTTPError, etc...)
print "An error occurred: ",$!, "\n"
end
end
我的别针/ _form.html.erb
<%= simple_form_for(@pin, html: { class: "form-horizontal"}) do |f| %>
<%= f.error_notification %>
<%= f.full_error :image_file_size, class: "alert alert-error" %>
<%= f.full_error :image_content_type, class: "alert alert-error" %>
<%= f.input :image, label: "Upload an image" %>
<%= f.input :image_url, label: false, placeholder: "http://" %>
<%= f.input :description, as: :text, input_html: { rows: "3" } %>
<div class="form-actions">
<%= f.button :submit, class: "btn btn-primary" %>
</div>
<% end %>
最后，我的Pins控制器很标准：
def new
@pin = current_user.pins.build
respond_to do |format|
format.html # new.html.erb
format.json { render json: @pin }
end
end
def create
@pin = current_user.pins.build(params[:pin])
respond_to do |format|
if @pin.save
format.html { redirect_to @pin, notice: 'Pin was successfully created.' }
format.json { render json: @pin, status: :created, location: @pin }
else
format.html { render action: "new" }
format.json { render json: @pin.errors, status: :unprocessable_entity }
end
end
end
好像它一遍又一遍地运行download_remote_image。
答案 0 :(得分：1)
在阅读'before_validation'上的rails文档之后，似乎如果你没有指定动作，即（before_validation：download_remote_image，：on =＆gt;：create），那么它每次都会运行被调用的方法改变了。在这种情况下，调用before_validation方法，然后在方法中，通过'self.image ='更改对象。如果未指定'on create'，则会在此阶段再次调用before_validation，从而重新启动download_remote_image方法。当它到达'self.image ='时，它再次调用它，依此类推。所以可以添加'：on =＆gt; ：在验证之前创建'或者在通过诸如'return if self.image.present？'之类的语句启动方法之前检查图像对象是否已经存在。
我对rails非常陌生，所以这个想法可能存在缺陷，但这对我来说很有意义。