README.rdoc

README.rdoc
Last Update: 2022-06-28 09:27:52 -0700

AutoForme

AutoForme is an administrative web front end to an ORM that uses Forme [1] for building the HTML forms. It is designed to integrate easily into web frameworks, and currently supports Roda, Sinatra, and Rails. The only currently supported ORM is Sequel::Model.

  1. github.com/jeremyevans/forme

Installation

gem install autoforme

Links

Demo Site

autoforme-demo.jeremyevans.net

RDoc

autoforme.jeremyevans.net

Source

github.com/jeremyevans/autoforme

Discussion Forum

github.com/jeremyevans/autoforme/discussions

Bug Tracker

github.com/jeremyevans/autoforme/issues

Features

  • Create, update, edit, and view model objects

  • Browse and search model objects

  • Edit many-to-many relationships for model objects

  • Easily access associated objects

  • Support autocompletion for all objects

  • Allow customization for all likely configuration points, using any parameters available in the request

Basic Configuration

AutoForme is configured using a fairly simple DSL. Here is an example for Sinatra:

class App < Sinatra::Base
  AutoForme.for(:sinatra, self) do
    order [:name]

    model Artist do
      columns [:name]
    end
    model Album do
      columns [:artist, :name]
    end
  end
end

Let’s break down how this works. You setup AutoForme using AutoForme.for, which takes 2 arguments, the controller type symbol (currently either :sinatra, :roda, or :rails), and the controller class (either a Sinatra::Base, Roda, or ActionController::Base subclass). You pass AutoForme.for a block, which is instance evaled at the framework level. This level sets the defaults.

The order call in the framework block sets the default order for all models.

The model calls in the framework block take a ORM model class. As only Sequel is currently supported, this should be a Sequel::Model subclass. The block passed to the model method is instance evaled at the model level, and sets the configuration for that model. In this example, the Artist model will only show the name column, and the Album model will only show the artist association and the name column.

In your application, you can then to go ‘/Artist/browse’ or ‘/Album/browse’ to get to the web UI exposed to AutoForme.

Design

Principles

  • Use Forme to generate the forms

  • Do not modify/extend model or controller classes

  • Assume that the web framework provides the layout

  • Do not use templates, render form objects to strings

  • Use a block-based DSL in the controller for configuration

  • Allow customization on a per-request basis for everything

Basic Implementation

The web framework controllers call AutoForme.for to create AutoForme::Framework instances, which contain and set default values for AutoForme::Model instances.

When a request comes in from the web framework, the AutoForme::Framework instance wraps request-level data in a AutoForme::Request. Then it creates an AutoForme::Action to handle this request. The AutoForme::Action either returns a string that the web framework then renders, or it redirects to another page.

Advanced Configuration

AutoForme doesn’t have all that many features compared to other admin frameworks, but the features it does have are extremely flexible.

Most of the configuration you’ll do in AutoForme is at the model level (in the context of an AutoForme::Model instance), so we’ll start looking at the customization options there. The most common options are probably:

columns

This is an array of column/association name symbols to use for the model.

column_options

This is a hash of column options for the model, keyed by column symbol, with values that are hashes of column options.

order

This is an expression or an array of expressions by which to order returned rows.

Note that for each of the customization options, you can do per-request customization by using a proc which is called with the type symbol and request (AutoForme::Request instance), which should return an appropriate object.

columns

Proc called with type symbol and request, should return array of column/association symbols

column_options

Proc called with column/association symbol, type symbol and request, should return hash of column options.

order

Proc called with type symbol and request, should return expression or array of expressions by which to order returned rows.

Below is brief description of other available options. Note that just like the above options you can use Procs with most of these options to do customization on a per-request basis.

association_links

Array of association symbols for associations to display on the show/edit pages, can also be set to :all for all associations or :all_except_mtm for all associations except many to many associations.

autocomplete_options

Enable autocompletion for this model, with the given options. The following keys are respected:

:callback

Proc called with dataset and options hash containing :type, :request, and :query

:display

A SQL expression to search on and display in the result

:limit

The number of results to return

:filter

Similar to callback, but overriding the default filter (a case insensitive substring search on display)

eager

Array of associations to eagerly load in separate queries

eager_graph

Array of associations to eager load in the same query (necessary if order or filter refers to them)

filter

A Proc called with a dataset, type symbol, and request that can be used to filter the available rows. Can be used to implement access control.

redirect

A Proc called with an object, type symbol, and request that can be used to override the default redirecting after form submittal.

inline_mtm_associations

Array of many to many association symbols to allow editing on the edit page

lazy_load_association_links

Whether to show the association links directly on the show/edit pages, or to load them via ajax on request

mtm_associations

Array of many to many association symbols to support editing on a separate page

per_page

Number of records to show per page on the browse and search pages

session_value

Sets up a filter and before_create hook that makes it so access is limited to objects where the object’s column value is the same as the session value with the same name.

supported_actions

Array of action symbols to support for the model, should be a subset of

:browse, :new, :show, :edit, :delete, :search, :mtm_edit

These options are related to displayed output:

form_attributes

Hash of attributes to use for any form tags

form_options

Hash of Forme::Form options to pass for any forms created

class_display_name

The string to use on pages when referring to the model class. This defaults to the full class name.

display_name

The string to use when referring to a model instance. Can either be a symbol representing an instance method call, or a Proc called with the model object, the model object and type symbol, or the model object, type symbol, and request, depending on the arity of the Proc.

link_name

The string to use in links for the class. This defaults to class_display_name.

edit_html

The html to use for a particular object edit field. Should be a proc that takes the model object, column symbol, type symbol, and request and returns the html to use.

page_footer

Override the default footer used for pages

page_header

Override the default header used for pages

show_html

The html to use for displaying the value for an object field. Should be a proc that takes the model object, column symbol, type symbol, and request and returns the html to use.

table_class

The html class string to use for the browse and search tables

view_options

Hash with options passed when rendering the view (how these options are used varies in each of the supported web frameworks), e.g. view_options: {:layout => :formelayout}

These hook options should be callable objects that are called with the model object and the request.

after_create

Called after creating the object

after_destroy

Called after destroying the object

after_update

Called after updating the object

before_create

Called before creating the object

before_destroy

Called before destroy the object

before_edit

Called before displaying object on edit page

before_new

Called before displaying object on new page

before_update

Called before updating the object

There’s also an addition before_action hook that is called with the type symbol of the request, and the request before every page.

In addition to being specified at the model level, almost all of these options can be specified at the framework level, where they operate as default values for models that don’t specify the options. Just like the model level, the framework level also allows customization on a per request basis, though framework-level Procs generally take the model class as an initial argument (in addition to the type symbol and request).

Additionally, AutoForme.for accepts a :prefix option that controls where the forms are mounted:

AutoForme.for(:sinatra, self, :prefix=>'/path/to') do
  model Artist
end

Means you can go to /path/to/Artist/browse to browse the artists.

Javascript

By default, AutoForme requires no javascript. The only optional part of AutoForme that requires javascript is the autocompleting. AutoForme also has javascript support for the progressive enhancement of the following:

  • Loading association links via ajax if lazy_load_association_links is true.

  • Adding and removing many-to-many associated objects via ajax for inline_mtm_associations

AutoForme’s javascript support is contained in the autoforme.js file in the root of the repository. AutoForme’s autocompleting support also requires github.com/Pixabay/JavaScript-autoComplete

Make sure to load the autoforme.js file after the DOM content has been loaded, such as at the end of the body.

Reloading Code

By default, AutoForme stores classes by reference. This can cause issues when using code reloading in development environments. You can call register_by_name to set Autoforme to store classes by name, so that if a class is removed and reloaded (giving a new class reference), it will use the new class instead of the reference to the old class. Example:

class App < Sinatra::Base
  AutoForme.for(:sinatra, self) do
    register_by_name
    model Artist
  end
end

Rails

Because Rails separates routing from request handling, it can be little awkward to use AutoForme in Rails development mode. The best way to handle it is to call AutoForme.for in the related controller file, and have an initializer reference the controller class, causing the controller file to be loaded.

Roda

Because Roda uses a routing tree, unlike Rails and Sinatra, with Roda you need to dispatch to the autoforme routes at the point in the routing tree where you want to mount them. Additionally, the Roda support offers a Roda plugin for easier configuration.

To mount the autoforme routes in the root of the application, you could do:

class App < Roda
  plugin :autoforme do
    model Artist
  end

  route do
    # rest of routing tree
    autoforme
  end
end

To mount the routes in a subpath:

class App < Roda
  plugin :autoforme do
    model Artist
  end

  route do
    r.on "admin" do
      autoforme
    end

    # rest of routing tree
  end
end

To handle multiple autoforme configurations, mounted at different subpaths:

class App < Roda
  plugin :autoforme

  autoforme(name: 'artists') do
    model Artist
  end
  autoforme(name: 'albums') do
    model Album
  end

  route do
    r.on "artists" do
      autoforme('artists')
    end
    r.on "albums" do
      autoforme('albums')
    end

    # rest of routing tree
  end
end

TODO

  • capybara-webkit tests for ajax behavior

  • read_only fields for edit page

  • one_to_many/many_to_many associations in columns

  • configurable searching

  • nested form objects

License

MIT

Author

Jeremy Evans <code@jeremyevans.net>