* to_excel 1.0

lib/to_excel.rb

@@ -0,0 +1,40 @@
+class Array
+  def to_excel(options = {})
+    output = '<?xml version="1.0" encoding="UTF-8"?><Workbook xmlns:x="urn:schemas-microsoft-com:office:excel" xmlns:ss="urn:schemas-microsoft-com:office:spreadsheet" xmlns:html="http://www.w3.org/TR/REC-html40" xmlns="urn:schemas-microsoft-com:office:spreadsheet" xmlns:o="urn:schemas-microsoft-com:office:office"><Worksheet ss:Name="Sheet1"><Table>'
+
+    if self.first.is_a?(Array) && self.first.any?
+      unless options[:headers] == false
+        output << "<Row>"
+
+        if options[:headers].is_a? Array
+          options[:headers].each do |title|
+            output << "<Cell><Data ss:Type=\"String\">#{title}</Data></Cell>"
+          end  
+        else  
+          klasses = self.map(&:first).map(&:class)
+          klasses.each do |klass|
+            options[:map][klass].each do |attribute|
+             output << "<Cell><Data ss:Type=\"String\">#{klass.human_attribute_name(attribute)}</Data></Cell>"
+            end 
+          end
+        end
+
+        output << "</Row>"
+      end
+
+      (0..self.map(&:length).max - 1).each do |n|
+        items = self.map {|collection| collection[n] || collection.first.class.new}
+        output << "<Row>"
+        items.each do |item|
+          options[:map][item.class].each do |column|
+            value = column.is_a?(Array) ? column.inject(item){|result,column| result.send(column) if result} : item.send(column)
+            output << "<Cell><Data ss:Type=\"#{value.is_a?(Integer) ? 'Number' : 'String'}\">#{value}</Data></Cell>"
+          end
+        end
+        output << "</Row>"
+      end
+   end
+
+   output << '</Table></Worksheet></Workbook>'
+  end
+end

test/to_excel_helper.rb

@@ -0,0 +1,49 @@
+begin
+  require 'rubygems'
+  require 'test/unit'
+  require 'active_support'
+  require 'to_excel'
+end
+
+class User
+  COLUMNS = %w(id name age)
+
+  attr_accessor *COLUMNS
+
+  def self.human_attribute_name(attribute)
+    attribute.to_s.humanize
+  end
+
+  def initialize(params={})
+    params.each { |key, value| self.send("#{key}=", value); }
+    self
+  end
+
+  def attributes
+    COLUMNS.inject({}) { |attributes, attribute| attributes.merge(attribute => send(attribute)) }
+  end
+
+  def is_old?
+    age > 40
+  end
+end
+
+class Computer
+  COLUMNS = %w(id brand portable user)
+
+  attr_accessor *COLUMNS
+
+  def self.human_attribute_name(attribute)
+    attribute.to_s.humanize
+  end
+
+  def initialize(params={})
+    params.each { |key, value| self.send("#{key}=", value); }
+    self
+  end
+
+  def attributes
+    COLUMNS.inject({}) { |attributes, attribute| attributes.merge(attribute => send(attribute)) }
+  end
+
+end

test/to_excel_test.rb

@@ -0,0 +1,104 @@
+require  'to_excel_helper'
+
+class ToExcelTest < Test::Unit::TestCase
+
+  def setup
+    @users = [
+      User.new(:id => 1, :name => 'Dupont', :age => 25),
+      User.new(:id => 2, :name => 'Martin', :age => 22)
+    ]
+    @computers =[
+      Computer.new(:id => 1, :brand => 'Apple', :portable => true, :user => @users.first),
+      Computer.new(:id => 2, :brand => 'Dell', :portable => false, :user => @users[1])
+    ]
+  end
+
+  def test_should_be_array_of_arrays_not_empty
+    assert_equal build_document(nil), [].to_excel
+    assert_equal build_document(nil), [[]].to_excel
+    assert_equal build_document(nil), @users.to_excel
+  end
+
+  def test_with_no_headers
+    document = build_document(
+      row(cell('Number', '25'), cell('Number', '1'), cell('String', 'Dupont')),
+      row(cell('Number', '22'), cell('Number', '2'), cell('String', 'Martin'))
+    )
+    assert_equal document, [@users].to_excel(:headers => false, :map => {User => [:age, :id, :name]})
+  end
+
+  def test_with_methods
+    document = build_document(
+      row(cell('String', 'Age'), cell('String', 'Id'), cell('String', 'Name'), cell('String', 'Is old?')),
+      row(cell('Number', '25'),  cell('Number', '1'),  cell('String', 'Dupont'),  cell('String', 'false')),
+      row(cell('Number', '22'),  cell('Number', '2'),  cell('String', 'Martin'), cell('String', 'false'))
+    )
+    assert_equal document, [@users].to_excel(:map => { User => [:age, :id, :name, :is_old?]})
+  end
+
+  def test_with_nested_attribute
+    document = build_document(
+      row(cell('String', 'Id'), cell('String', 'Username')),
+      row(cell('Number', '1'),  cell('String', 'Dupont')),
+      row(cell('Number', '2'),  cell('String', 'Martin'))
+    )
+    assert_equal document, [@computers].to_excel(:map => { Computer => [:id, [:user, :name]]})
+  end
+
+  def test_with_two_collections
+    document = build_document(
+      row(cell('String', 'Id'), cell('String', 'Name'), cell('String', 'Id'), cell('String', 'Brand')),
+      row(cell('Number', '1'),  cell('String', 'Dupont'),  cell('Number', '1'),  cell('String', 'Apple')),
+      row(cell('Number', '2'),  cell('String', 'Martin'),  cell('Number', '2'),  cell('String', 'Dell'))
+    )
+    assert_equal document, [@users, @computers].to_excel(:map => { User => [:id,:name], Computer => [:id,:brand]})
+  end
+
+  def test_with_one_collection
+    document = build_document(
+      row(cell('String', 'Id'), cell('String', 'Username')),
+      row(cell('Number', '1'),  cell('String', 'Dupont')),
+      row(cell('Number', '2'),  cell('String', 'Martin'))
+    )
+    assert_equal document, [@computers].to_excel(:map => {Computer => [:id,[:user, :name]]})
+  end
+
+  def test_should_render_empty_cells_unless_collections_of_same_size
+    @users << User.new(:id => 3, :name => 'Durand', :age => 23)
+    document = build_document(
+      row(cell('String', 'Id'), cell('String', 'Name'), cell('String', 'Id'), cell('String', 'Brand')),
+      row(cell('Number', '1'),  cell('String', 'Dupont'),  cell('Number', '1'),  cell('String', 'Apple')),
+      row(cell('Number', '2'),  cell('String', 'Martin'),  cell('Number', '2'),  cell('String', 'Dell')),
+      row(cell('Number', '3'),  cell('String', 'Durand'),  cell('String', ''),  cell('String', ''))
+    )
+    assert_equal document, [@users, @computers].to_excel(:map => { User => [:id,:name], Computer => [:id,:brand]})
+  end
+
+  def test_with_own_header
+    document = build_document(
+      row(cell('String', 'User Id'), cell('String', 'Nom'), cell('String', 'Computer Id'), cell('String', 'Marque')),
+      row(cell('Number', '1'),  cell('String', 'Dupont'),  cell('Number', '1'),  cell('String', 'Apple')),
+      row(cell('Number', '2'),  cell('String', 'Martin'),  cell('Number', '2'),  cell('String', 'Dell'))
+    )
+    header = ['User Id', 'Nom', 'Computer Id', 'Marque']
+    assert_equal document, [@users, @computers].to_excel(:map => { User => [:id,:name], Computer => [:id,:brand]}, :headers => header)    
+  end
+  #TODO generate default map from class columns if no map option passed
+  def test_with_no_map_option
+
+  end
+
+private
+
+  def build_document(*rows)
+    "<?xml version=\"1.0\" encoding=\"UTF-8\"?><Workbook xmlns:x=\"urn:schemas-microsoft-com:office:excel\" xmlns:ss=\"urn:schemas-microsoft-com:office:spreadsheet\" xmlns:html=\"http://www.w3.org/TR/REC-html40\" xmlns=\"urn:schemas-microsoft-com:office:spreadsheet\" xmlns:o=\"urn:schemas-microsoft-com:office:office\"><Worksheet ss:Name=\"Sheet1\"><Table>#{rows}</Table></Worksheet></Workbook>"
+  end
+
+  def row(*cells)
+    "<Row>#{cells}</Row>"
+  end
+
+  def cell(type, content)
+    "<Cell><Data ss:Type=\"#{type}\">#{content}</Data></Cell>"
+  end
+end