added Sequel support

Author: sferik

lib/abstract_model.rb

@@ -24,6 +24,15 @@ def self.all
           @models << new(model) if model
         end
         @models.sort!{|a, b| a.model.to_s <=> b.model.to_s}
+      when :sequel
+        Dir.glob(Merb.dir_for(:model) / Merb.glob_for(:model)).each do |filename|
+          # FIXME: This heuristic for finding Sequel models could be too strict
+          File.read(filename).scan(/^class ([\w\d_\-:]+) < Sequel::Model$/).flatten.each do |m|
+            model = lookup(m.to_s.to_sym)
+            @models << new(model) if model
+          end
+        end
+        @models.sort!{|a, b| a.model.to_s <=> b.model.to_s}
       else
         raise "MerbAdmin does not support the #{Merb.orm} ORM"
       end
@@ -42,6 +51,8 @@ def self.lookup(model_name)
         return model if model.superclass == ActiveRecord::Base
       when :datamapper
         return model if model.include?(DataMapper::Resource)
+      when :sequel
+        return model if model.superclass == Sequel::Model
       end
       nil
     end
@@ -59,6 +70,9 @@ def initialize(model)
       when :datamapper
         require 'datamapper_support'
         self.extend(DatamapperSupport)
+      when :sequel
+        require 'sequel_support'
+        self.extend(SequelSupport)
       else
         raise "MerbAdmin does not support the #{Merb.orm} ORM"
       end

lib/merb-admin/slicetasks.rb

@@ -51,6 +51,27 @@
       end
     end
 
+    desc "Copies sample models, copies and runs sample migrations, and loads sample data"
+    task :sequel => ["sequel:copy_sample_models", "sequel:copy_sample_migrations", "sequel:migrate", "load_sample_data"]
+    namespace :sequel do
+      desc "Copies sample models into your app"
+      task :copy_sample_models do
+        copy_models(:sequel)
+      end
+
+      desc "Copies sample migrations into your app"
+      task :copy_sample_migrations do
+        copy_migrations(:sequel)
+      end
+
+      desc "Perform migration using migrations in schema/migrations"
+      task :migrate do
+        require 'sequel/extensions/migration'
+        Rake::Task["sequel:db:migrate"].reenable
+        Rake::Task["sequel:db:migrate"].invoke
+      end
+    end
+
     desc "Loads sample data into your app"
     task :load_sample_data do
       load_data
@@ -63,13 +84,13 @@
 
 def load_data
   begin
-    require "mlb"    
+    require "mlb"
   rescue LoadError => e
     puts "LoadError: #{e}"
     puts "gem install mlb -s http://gemcutter.org"
     return
   end
-  
+
   puts "Loading current MLB leagues, divisions, teams, and players"
   MLB.teams.each do |mlb_team|
     unless league = MerbAdmin::AbstractModel.new("League").first(:conditions => ["name = ?", mlb_team.league])

lib/sequel_support.rb

@@ -0,0 +1,309 @@
+require 'sequel'
+require 'sequel/extensions/pagination'
+
+class Sequel::Model
+=begin
+  # Intialize each column to the default value for new model objects
+  def after_initialize
+    super
+    model.columns.each do |x|
+      if !@values.include?(x) && db_schema[x][:allow_null]
+        send("#{x}=", db_schema[x][:ruby_default])
+      end
+    end
+  end
+=end
+
+  # Return an empty array for *_to_many association methods for new model objects
+  def _load_associated_objects(opts)
+    opts.returns_array? && new? ? [] : super
+  end
+end
+
+module MerbAdmin
+  class AbstractModel
+    module SequelSupport
+      def get(id)
+        model.first(:id => id).extend(InstanceMethods)
+      end
+
+      def count(options = {})
+        if options[:conditions] && !options[:conditions].empty?
+          # If options[:conditions] isn't cloned, Sequel eats the first condition!
+          model.where(options[:conditions].clone).count
+        else
+          model.count
+        end
+      end
+
+      def first(options = {})
+        sort = options.delete(:sort) || :id
+        sort_order = options.delete(:sort_reverse) ? :desc : :asc
+
+        if options[:conditions] && !options[:conditions].empty?
+          # If options[:conditions] isn't cloned, Sequel eats the first condition!
+          model.order(sort.to_sym.send(sort_order)).first(options[:conditions].clone).extend(InstanceMethods)
+        else
+          model.order(sort.to_sym.send(sort_order)).first.extend(InstanceMethods)
+        end
+      end
+
+      def all(options = {})
+        offset = options.delete(:offset)
+        limit = options.delete(:limit)
+
+        sort = options.delete(:sort) || :id
+        sort_order = options.delete(:sort_reverse) ? :desc : :asc
+
+        if options[:conditions] && !options[:conditions].empty?
+          # If options[:conditions] isn't cloned, Sequel eats the first condition!
+          model.where(options[:conditions].clone).order(sort.to_sym.send(sort_order))
+        else
+          model.order(sort.to_sym.send(sort_order))
+        end
+      end
+
+      def paginated(options = {})
+        page = options.delete(:page) || 1
+        per_page = options.delete(:per_page) || MerbAdmin[:per_page]
+        page_count = (count(options).to_f / per_page).ceil
+
+        sort = options.delete(:sort) || :id
+        sort_order = options.delete(:sort_reverse) ? :desc : :asc
+
+        if options[:conditions] && !options[:conditions].empty?
+          # If options[:conditions] isn't cloned, Sequel eats the first condition!
+          [page_count, model.paginate(page.to_i, per_page).where(options[:conditions].clone).order(sort.to_sym.send(sort_order))]
+        else
+          [page_count, model.paginate(page.to_i, per_page).order(sort.to_sym.send(sort_order))]
+        end
+      end
+
+      def create(params = {})
+        model.create(params)
+      end
+
+      def new(params = {})
+        model.new(params).extend(InstanceMethods)
+      end
+
+      def destroy_all!
+        model.all.each do |object|
+          object.destroy
+        end
+      end
+
+      def has_many_associations
+        associations.select do |association|
+          association[:type] == :has_many
+        end
+      end
+
+      def has_one_associations
+        associations.select do |association|
+          association[:type] == :has_one
+        end
+      end
+
+      def belongs_to_associations
+        associations.select do |association|
+          association[:type] == :belongs_to
+        end
+      end
+
+      def associations
+        model.all_association_reflections.map do |association|
+          {
+            :name => association_name_lookup(association),
+            :pretty_name => association_pretty_name_lookup(association),
+            :type => association_type_lookup(association),
+            :parent_model => association_parent_model_lookup(association),
+            :parent_key => association_parent_key_lookup(association),
+            :child_model => association_child_model_lookup(association),
+            :child_key => association_child_key_lookup(association),
+          }
+        end
+      end
+
+      def properties
+        model.columns.map do |property|
+          {
+            :name => property,
+            :pretty_name => property.to_s.gsub(/_id$/, "").gsub("_", " ").capitalize,
+            :type => property_type_lookup(property),
+            :length => property_length_lookup(property),
+            :nullable? => model.db_schema[property][:allow_null],
+            :serial? => model.db_schema[property][:primary_key],
+          }
+        end
+      end
+
+      private
+
+      def property_type_lookup(property)
+        case model.db_schema[property][:db_type]
+        when /\A(?:medium|small)?int(?:eger)?(?:\((?:\d+)\))?\z/io
+          :integer
+        when /\Atinyint(?:\((\d+)\))?\z/io
+          :boolean
+        when /\Abigint(?:\((?:\d+)\))?\z/io
+          :integer
+        when /\A(?:real|float|double(?: precision)?)\z/io
+          :float
+        when 'boolean'
+          :boolean
+        when /\A(?:(?:tiny|medium|long|n)?text|clob)\z/io
+          :text
+        when 'date'
+          :date
+        when /\A(?:small)?datetime\z/io
+          :datetime
+        when /\Atimestamp(?: with(?:out)? time zone)?\z/io
+          :datetime
+        when /\Atime(?: with(?:out)? time zone)?\z/io
+          :time
+        when /\An?char(?:acter)?(?:\((\d+)\))?\z/io
+          :string
+        when /\A(?:n?varchar|character varying|bpchar|string)(?:\((\d+)\))?\z/io
+          :string
+        when /\A(?:small)?money\z/io
+          :big_decimal
+        when /\A(?:decimal|numeric|number)(?:\((\d+)(?:,\s*(\d+))?\))?\z/io
+          :big_decimal
+        when 'year'
+          :integer
+        else
+          :string
+        end
+      end
+
+      def property_length_lookup(property)
+        case model.db_schema[property][:db_type]
+        when /\An?char(?:acter)?(?:\((\d+)\))?\z/io
+          $1 ? $1.to_i : 255
+        when /\A(?:n?varchar|character varying|bpchar|string)(?:\((\d+)\))?\z/io
+          $1 ? $1.to_i : 255
+        else
+          nil
+        end
+      end
+
+      def association_name_lookup(association)
+        case association[:type]
+        when :one_to_many
+          if association[:one_to_one]
+            association[:name].to_s.singularize.to_sym
+          else
+            association[:name]
+          end
+        when :many_to_one
+            association[:name]
+        else
+          raise "Unknown association type"
+        end
+      end
+
+      def association_pretty_name_lookup(association)
+        case association[:type]
+        when :one_to_many
+          if association[:one_to_one]
+            association[:name].to_s.singularize.gsub('_', ' ').capitalize
+          else
+            association[:name].to_s.gsub('_', ' ').capitalize
+          end
+        when :many_to_one
+          association[:name].to_s.gsub('_', ' ').capitalize
+        else
+          raise "Unknown association type"
+        end
+      end
+
+      def association_type_lookup(association)
+        case association[:type]
+        when :one_to_many
+          if association[:one_to_one]
+            :has_one
+          else
+            :has_many
+          end
+        when :many_to_one
+          :belongs_to
+        else
+          raise "Unknown association type"
+        end
+      end
+
+      def association_parent_model_lookup(association)
+        case association[:type]
+        when :one_to_many
+          association[:model]
+        when :many_to_one
+          Object.const_get(association[:class_name])
+        else
+          raise "Unknown association type"
+        end
+      end
+
+      def association_parent_key_lookup(association)
+        [:id]
+      end
+
+      def association_child_model_lookup(association)
+        case association[:type]
+        when :one_to_many
+          Object.const_get(association[:class_name])
+        when :many_to_one
+          association[:model]
+        else
+          raise "Unknown association type"
+        end
+      end
+
+      def association_child_key_lookup(association)
+        case association[:type]
+        when :one_to_many
+          association[:keys]
+        when :many_to_one
+          ["#{association[:class_name].snake_case}_id".to_sym]
+        else
+          raise "Unknown association type"
+        end
+      end
+
+      module InstanceMethods
+        def id
+          super
+        end
+
+        def save
+          super
+        end
+
+        def destroy
+          super
+        end
+
+        def update_attributes(attributes)
+          # NOTE: Not sure why calling update(attributes) raises
+          # Argument Error: wrong number of arguments (1 for 0)
+          # but this seems to work:
+          set(attributes)
+          save
+        end
+
+        def errors
+          super
+        end
+
+        def clear_association(association)
+          association.clear # FIXME!
+        end
+
+        def reset
+          super
+        end
+      end
+
+    end
+  end
+end