CsvComposer

Csv composer is a flexible and generic csv writer and exporter. Allows you to easily control whatever you want to do in each step of csv making, such as how to:

• iterate over the collection
• generate file header
• generate rows
• export final output

Easy to set up, just extend composer entities to create your own custom csv's or use the generic one.

Installation

Add this line to your application's Gemfile:

gem 'csv_composer'

And then execute:

$ bundle

Or install it yourself as:

$ gem install csv_composer

Usage

Basic usage:

    collection = [
      { id: 'element1', value: 'value1'},
      { id: 'element2', value: 'value2'},
      { id: 'element3', value: 'value3'}            
    ]

    exporter = CsvComposer::Generic.new
    exporter.compose(collection)

Where collection could be everything that includes Enumerable module (and implements each method). This way you are able to implement your custom iterators.

Custom csvs exporters

You can create your own custom exporters just extending CsvComposer::Base.

Override your own custom 'columns_mapping' to map every kind of object (in the collection) to csv value using lambdas:

    def generic_lambda
      ->(item, key) { item[key] || '' }
    end

    def columns_mapping
      [
        { id: 'Id', key: :id, lambda: generic_lambda },
        { id: 'Value', key: :value, lambda: generic_lambda }
      ]
    end

Create and set your own custom Header processors extending 'CsvComposer::HeaderProcessors::Base' and your own custom ItemProcessors 'extending CsvComposer::ItemProcessors::Base'

Finally create and set your own custom file exporters extending 'CsvComposer::FileExporters::Base' to export csv to wherever location you want such as a file, upload it to the cloud, etc.

Optionally you can send a second parameter to 'compose' method with a hash containing custom options that will be sent into both header and item processor that you can use when overriding them.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the 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/Twistbioscience/csv_composer