LpCSVExportableWithStream

This is an extension of LaunchPadLab/lp_csv_exportable, let you can export data with Live stream.

When Export lager data, rails will fetch all data what you need and make generate scv data. Your download will start after scv file generated, that's This will make your project seems to broken.

But Live Stream will generate file while downloading. It's good for your user experience

Installation

Add this line to your application's Gemfile:

gem 'lp_csv_exportable_with_stream'

And then execute:

$ bundle install

Or install it yourself as:

$ gem install lp_csv_exportable_with_stream

Usage

1. Follow the LaunchPadLab/lp_csv_exportable basic usage. Like this

class ExportUsers
  include LpCSVExportable::CanExportAsCSV

  column :first_name
  column :last_name
  column :email
  column 'User Role', model_methods: %i[membership name]
end

2. And add include LpCSVExportable::WithStream below include LpCSVExportable::CanExportAsCSV

  include LpCSVExportable::CanExportAsCSV
  include LpCSVExportable::WithStream

  column :first_name

3. finally, replace .to_csv with .to_csv_lazy(self)

def index
    users = User.all

    respond_to do |format|
      format.csv do
        export = ExportUsers.new
        export.collection = users
        export.to_csv_lazy(self)
      end
    end
  end

Filename Setting

You can setting your filename in Export Class, just add self.filename = "Your File Name"

class ExportUsers
  include LpCSVExportable::CanExportAsCSV
  include LpCSVExportable::WithStream

  self.filename = "Your File Name" # This is base file name

Also, you can add prefix ro suffix for your file name when export. maybe exported date and so on.

respond_to do |format|
  format.csv do
    export = ExportUsers.new
    export.collection = users
    export.filename_prefix = "#{Date.today.strftime("%Y-%m-%d %H:%M")}" # add prefix to your base filename
    export.filename_suffix = "version 2" # add suffix to your base filename
    export.to_csv_lazy(self)
  end
end

Prevent N + 1 query

If your need to prevent n + 1 query, you can add self.collection_includes = [:your, :relations], it will automatically includes relations of your collection

class ExportUsers
  include LpCSVExportable::CanExportAsCSV
  include LpCSVExportable::WithStream

  self.filename = "Your File Name"
  self.collection_includes = [:address, :friends] # Equivalence with "collection.includes(:address, :friends)"

Note

What's N + 1 Query? Faster Rails: Eliminating N+1 queries

Development

After checking out the repo, run bin/setup to install dependencies. 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 the created tag, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/[USERNAME]/lp_csv_exportable_with_stream.

License

The gem is available as open source under the terms of the MIT License.