Rails Admin Import functionality
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README.md

Rails Admin Import

Build Status

Plugin functionality to add generic import to Rails Admin from CSV, JSON and XLSX files

Installation

  • First, add to Gemfile:
gem "rails_admin_import", "~> 1.2"
  • Define configuration in config/initializers/rails_admin_import.rb:
RailsAdmin.config do |config|
  # REQUIRED:
  # Include the import action
  # See https://github.com/sferik/rails_admin/wiki/Actions
  config.actions do
    all
    import
  end

  # Optional:
  # Configure global RailsAdminImport options
  config.configure_with(:import) do |config|
    config.logging = true
  end

  # Optional:
  # Configure model-specific options using standard RailsAdmin DSL
  # See https://github.com/sferik/rails_admin/wiki/Railsadmin-DSL
  config.model 'User' do
    import do
      include_all_fields
      exclude_fields :secret_token
    end
  end
end
  • If you are using CanCanCan for authorization, add to ability.rb to specify which models can be imported:
cannot :import, :all
can :import, [User, Model1, Model2]

Usage

Model instances can be both created and updated from import data. Any fields can be imported as long as they are allowed by the model's configuration. Associated records can be looked up for both singular and plural relationships. Both updating existing records and associating records requires the use of mapping keys.

Mapping Keys

Every importable class has a mapping key that uniquely identifies its instances. The value for this field can then be provided in import data, either to update the existing record or to attach it through an association to another model. This concept exists because ids are often not constant when moving records between data stores.

For example, a User model may have an email field. When uploading a set of users where some already exist in our database, we can select "email" as our mapping key and then provide that field on each record in our data, allowing us to update existing records with matching emails.

Using a csv formatted example:

Email,First name,Last name
peter.gibbons@initech.com,Peter,Gibbons
michael.bolton@initech.com,Michael,Bolton

would look for existing users with those emails. If one was found, its name fields would be updated. Otherwise, a new one would be created.

Similarly, if each user has favorite books, we could set the mapping key for Book to be isbn and then include the isbn for their books within each user record. The syntax for this is to use the name of the associated model as the field name, no matter what actual mapping key has been selected. So a user record would have one or more fields named "Book" that include each associated book's ISBN.

Again using a csv formatted example:

Email, Book, Book, Book
peter.gibbons@initech.com, 9781119997870, 9780671027032
michael.bolton@initech.com, 9780446677479

would look up books with those ISBNs and attach them to those users.

Mapping keys can be selected on the import page. Their defaults can also be globally configured in the config file:

RailsAdmin.config do |config|
  config.model 'User' do
    import do
      mapping_key :email
    end
  end
end

Note that a matched record must exist when attaching associated models, or the imported record will fail and be skipped.

Complex associations (has_one ..., :through or polymorphic associations) need to be dealt with via custom logic called by one of the import hooks (see below for more detail on using hooks). If we wanted to import Services and attach them to a User, but the user relationship existed through an intermediary model called ServiceProvider, we could provide a user_email field in our records and handle the actual association with an import hook:

class Service < ActiveRecord::Base
  belongs_to :service_provider
  has_one :user, through: :service_provider

  def before_import_save(record)
    if (email = record[:user_email]) && (user = User.find_by_email(email))
      self.service_provider = user.service_provider
    end
  end
end

File format

The format is inferred by the extension (.csv, .json or .xlsx).

CSV

The first line must contain attribute names. They will be converted to lowercase and underscored (First Name ==> first_name).

For "many" associations, you may include multiple columns with the same header in the CSV file.

The repeated header may be singular or plural. For example, for a "children" association, you may have multiple "child" columns or multiple "children" column, each containing one lookup value for an associated record. Blank values are ignored.

Example

First name,Last name,Team,Team
Peter,Gibbons,IT,Management
Michael,Bolton,IT,

JSON

The file must be an array or an object with a root key the same name as the plural model name, i.e. the default Rails JSON output format with include_root_in_json on or off.

XLSX

The Microsoft Excel XLM format (XLSX) is supported, but not the old binary Microsoft Excel format (XLS).

The expected rows and columns are the same as for the CSV format (first line contains headers, multiple columns for "many" associations).

Configuration

Global configuration options

  • logging (default false): Save a copy of each imported file to log/import and a detailed import log to log/rails_admin_import.log

  • line_item_limit (default 1000): max number of items that can be imported at one time.

  • rollback_on_error (default false): import records in a transaction and rollback if there is one error. Only for ActiveRecord, not Mongoid.

  • header_converter (default lambda { ... }): a lambda to convert each CSV header text string to a model attribute name. The default header converter converts to lowercase and replaces spaces with underscores.

  • csv_options (default {}): a hash of options that will be passed to a new CSV instance

Model-specific configuration

Use standard RailsAdmin DSL to add or remove fields.

  • To change the default attribute that will be used to find associations on import, set mapping_key (default attribute is name)
RailsAdmin.config do |config|
  config.model 'Ball' do
    import do
      mapping_key :color
    end
  end
end
  • To include a specific list of fields:
RailsAdmin.config do |config|
  config.model 'User' do
    import do
      field :first_name
      field :last_name
      field :email
    end
  end
end
  • To exclude specific fields:
RailsAdmin.config do |config|
  config.model 'User' do
    import do
      include_all_fields
      exclude_fields :secret_token
    end
  end
end
  • To add extra fields that will be set as attributes on the model and that will be passed to the import hook methods:
RailsAdmin.config do |config|
  config.model 'User' do
    import do
      include_all_fields
      fields :special_import_token
    end
  end
end
RailsAdmin.config do |config|
  config.model 'User' do
    import do
      default_excluded_fields [:created_at, :updated_at]
    end
  end
end

Import hooks

Define instance methods on your models to be hooked into the import process, if special/additional processing is required on the data:

# some model
class User < ActiveRecord::Base
  def before_import_save(record)
    # Your custom special sauce
  end

  def after_import_save(record)
    # Your custom special sauce
  end
end

For example, you could

  • Set an attribute on a Devise User model to skip checking for a password when importing a new model.

  • Import an image into Carrierwave via a URL provided in the CSV.

def before_import_save(record)
  self.remote_image_url = record[:image] if record[:image].present?  
end

ORM: ActiveRecord and Mongoid

The gem is tested to work with ActiveRecord and Mongoid.

Support for Mongoid is early, so if you can suggest improvements (especially around importing embedded models), open an issue.

Eager loading

Since the import functionality is rarely used in many applications, some gems are autoloaded when first used during an import in order to save memory at boot.

If you prefer to eager load all dependecies at boot, use this line in your Gemfile.

gem "rails_admin_import", "~> 1.2.0", require: "rails_admin_import/eager_load"

Upgrading

  • Move global config to config.configure_with(:import) in config/initializers/rails_admin_import.rb.

  • Move the field definitions to config.model 'User' do; import do; // ... in config/initializers/rails_admin_import.rb.

  • No need to mount RailsAdminImport in config/routes.rb (RailsAdmin must still be mounted).

  • Update model import hooks to take 1 hash argument instead of 2 arrays with values and headers.

  • Support for importing file attributes was removed since I couldn't understand how it works. It should be possible to reimplement it yourself using post import hooks. Open an issue to discuss how to put back support for importing files into the gem.

Community-contributed translations

Run tests

  1. Clone the repository to your machine

    git clone https://github.com/stephskardal/rails_admin_import

  2. Run bundle install

  3. Run bundle exec rspec

The structure of the tests is taken from the Rails Admin gem.

Authors

Original author: Steph Skardal

Maintainer (since May 2015): Julien Vanier

Contributing

Everyone is encouraged to help improve this project. Here are a few ways you can help:

Copyright

Copyright (c) 2015 End Point, Steph Skardal and contributors. See LICENSE.txt for further details.