ActiveStorage::Exif::Analyzer

This gem packages a simple analyzer to extract EXIF metadata from supported files. "Supported files" means anything supported by ImageMagick - i.e. more than just JPEG.

The actual analyzer is very simple, and can be found in lib/active_storage/exif/analyzer if you would prefer to just drop this in app/analyzers in your codebase and prepend it to the analyzers list yourself.

Installation

Add this line to your application's Gemfile:

gem 'activestorage-exif-analyzer', require: "active_storage/exif/analyzer"

And then execute:

$ bundle

Or install it yourself as:

$ gem install activestorage-exif-analyzer

This gem will automatically add itself to the analyzer pipeline and run across any supported image files. If you wish to control the precise analyzer order, you can manipulate the ActiveStorage.analyzers array.

Usage

This gem automatically adds itself to the analysis pipeline, simply ensure that analysis is run on your uploaded files.

To manually see what kind of metadata is extracted from a particular blob, simply grab an attachment and pass the the blob directly to the analyzer:

ActiveStorage::Exif::Analyzer.new(ActiveStorage::Attachment.first.blob).metadata
 =>  {"width"=>4208,
    "height"=>3120,
    "analyzed"=>true,
    "exif"=> {
        "ApertureValue"=>"200/100",
        "ColorSpace"=>"1",
        "ComponentsConfiguration"=>"1, 2, 3, 0",
        "DateTimeDigitized"=>"2002:12:08 12:00:00",
        "DateTimeOriginal"=>"2015:09:26 18:15:50",
        # ...
    }}

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake to run the lint checks and tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/ackama/activestorage-exif-analyzer.