blitline_gem

Image processing in the cloud ruby gem

Ruby

Getting Started

You must first have a Blitline.com account to successfully use the gem. You can obtain one (free) by going to https://www.blitline.com

Once you have your account, you will need to find you APPLICATION_ID which you can get by logging in and clicking on the Account tab.

In you application environment, install the Blitline gem or add the Blitline gem to your Gemfile

$ gem install blitline

or…if you have a Gemfile

gem 'blitline'

You can find comprehensive documentation at http://helpdocs.blitline.com/

The method is as follows:

Once the gem is installed, you can start a Rails console and try the following:

$ blitline_service = Blitline.new
$ blitline_service.add_job_via_hash({
      "application_id"=>"YOUR_APP_ID",
      "src"=>"http://cdn.blitline.com/filters/boys.jpeg",
      "functions"=>[
          {
              "name"=>"resize_to_fit",
              "params"=>{
                  "width"=>100
              },
              "save"=>{
                  "image_identifier"=>"MY_CLIENT_ID"
              }
          }
      ]
  })
$ blitline_service.post_jobs

The resulting JSON will look something like:

{"results":{"images":[{"image_identifier":"MY_CLIENT_ID", "s3_url":"http://s3.amazonaws.com/blitline/9393939393/99/6CPGskk11mM-B8zaCYUJzqbw.jpg"}] ,"job_id":"4JVyFJBIhlpHNXLK-YClq5g"}}

This JSON contains:

Any error information that may have happened with the submit
A list of images
- Each image has an image_identifier, which is the image_identifier you used in the save params.
- Each image also has an s3_url which is the final destination of the image (once it is done processing).

GDPR Compliance

If you want all your processing to be done in the EU (and adhere to those GDPR standards), you must set the following Environenment Variable

  BLITLINE_DOMAIN=eu

This will cause all data to be posted to EU servers and all processing done on EU server. It may also increase performance if you S3 (or other) storage is in the EU.

Important!

This result does not indicate that the job is done! The job has been put on a queue and will be done shortly. The best
way to identify when the job is completed is by adding a postback_url to the job hash and we will call back that url
when we have completed the image processing.

As an alternative to blitline_service.post_jobs, you can use blitline_service.post_job_and_wait

$ blitline_service.post_job_and_wait_for_poll

Which will block, and using Blitline’s long polling functionality, return when the job is completed. There must be only one requested job. The returned result will look like

{"original_meta"=>{"width"=>720, "height"=>540}, "images"=>[{"image_identifier"=>"MY_CLIENT_ID", "s3_url"=>"http://s3.amazonaws.com/blitline/2013082822/20/7J6Izja0hkG7rvNj-MUJDfQ.jpg", "meta"=>{"width"=>100, "height"=>75}}], "job_id"=>"9hgxoQ10WI7YN2QcioUarbA"}

This JSON contains:

Any error information associated with the job
Metadata associated with the original image
A list of images processed.

In fact, this result will contain all the exact same information a Blitline postback would contain.

The example above is a trivial (and pretty uninteresting) demonstration of how to use the Blitline gem. You can find documentation about Blitline.com and it’s services by following the links below