csv exporter class almost done

app/objects/service/belboon_article_exporter.rb

@@ -1,14 +1,8 @@
-require 'exporter'
-
 class BelboonArticleExporter
-  include CSVExporter
-
-  def initialize &block
-    super
-  end
+  @@csv_options = { col_sep: ';',  encoding: 'utf-8' }
 
-  export_mapping do
-    field 'Merchant_ProductNumber' => 'slug',
+  EXPORT_MAPPING = {
+    'Merchant_ProductNumber' => 'slug',
     'EAN_Code' => 'gtin',
     'Product_Title' => 'title',
     'Manufacturer' => nil,
@@ -38,20 +32,39 @@ def initialize &block
     'Optional_3' => nil,
     'Optional_4' => nil,
     'Optional_5' => nil
-  end
+  }
 
-  export_header %w(
-    Merchant_ProductNumber EAN_Code Product_Title Manufacturer Brand
-    Price Price_old Currency Valid_From Valid_To DeepLink_URL
-    Into_Basket_URL Image_Small_URL Image_Small_HEIGHT Image_Small_WIDTH
-    Image_Large_URL Image_Large_HEIGHT Image_Large_WIDTH Merchant_Product_Category
-    Keywords Product_Description_Short Product_Description_Long Last_Update
-    Shipping Availability Optional_1 Optional_2 Optional_3 Optional_4 Optional_5
-  )
+  EXPORT_HEADER = %w(Merchant_ProductNumber EAN_Code Product_Title Manufacturer Brand Price Price_old Currency Valid_From Valid_To DeepLink_URL Into_Basket_URL Image_Small_URL Image_Small_HEIGHT Image_Small_WIDTH Image_Large_URL Image_Large_HEIGHT Image_Large_WIDTH Merchant_Product_Category Keywords Product_Description_Short Product_Description_Long Last_Update Shipping Availability Optional_1 Optional_2 Optional_3 Optional_4 Optional_5)
 
-  def file_name
-    Rails.env == 'development' ?
+  FILE_NAME = Rails.env == 'development' ?
     "#{ Rails.root }/public/fairmondo_articles.csv" :
     '/var/www/fairnopoly/shared/public/system/fairmondo_articles.csv'
+
+  class << self
+    def export(user)
+      CSV.open(FILE_NAME, 'wb', @@csv_options) do |line|
+        line << EXPORT_HEADER
+
+        exportable_articles_for(user).find_each do |article|
+          line << line_for(article)
+        end
+      end
+    end
+
+    def line_for article
+      attrs = []
+      EXPORT_HEADER.each do |attr|
+        begin
+          attrs << "'#{ article.instance_eval(EXPORT_MAPPING[attr]) }'"
+        rescue
+          attrs << "'#{ EXPORT_MAPPING[attr] }'"
+        end
+      end
+      attrs
+    end
+
+    def exportable_articles_for user
+      user.articles.belboon_trackable.includes(:images)
+    end
   end
 end

app/objects/service/exporter.rb

@@ -1,18 +1,19 @@
-module CSVExporter
-  attr_accessor :export_mapping, :export_header
-
+class Exporter
   def initialize &block
-    instance_eval &block if block
+    @export_mapping = {}
+    @file_name = ''
+    @csv_options ||= { col_sep: ';',  encoding: 'utf-8' }
+
+    instance_eval(&block) if block_given?
   end
 
-  def self.included base
-    base.extend ClassMethods
+  def build &block
+    initialize(&block)
   end
 
   def export &block
-    CSV.open(file_name, 'wb', csv_options) do |line|
-      binding.pry
-      line << export_header
+    CSV.open(@file_name, 'wb', @csv_options) do |line|
+      line << @export_mapping.keys
 
       yield.find_each do |item|
         line << generate_line_for(item)
@@ -22,45 +23,42 @@ def export &block
 
   private
 
-  def csv_options
-    { col_sep: ';',  encoding: 'utf-8' }
-  end
-
   def generate_line_for item
     attrs = []
-    @export_header.each do |attr|
-      begin
-        attrs << "'#{ item.instance_eval(export_mapping[attr]) }'"
-      rescue
-        attrs << "'#{ export_mapping[attr] }'"
+    @export_mapping.each do |_key, value|
+      case
+      when empty_or_nil_in?(value)
+        attrs << value
+      when string_or_symbol_in?(value)
+        attrs << item.instance_eval(value.to_s)
+      when value.is_a?(Proc)
+        attrs << item.instance_exec(&(value)) if proc_in?(value)
       end
     end
     attrs
   end
 
-  module ClassMethods
-    def export_mapping
-      @export_mapping ||= {}
-    end
+  def empty_or_nil_in? value
+    value == nil || value == ''
+  end
 
-    def export_header
-      @export_header ||= []
-    end
+  def string_or_symbol_in? value
+    value.is_a?(String) || value.is_a?(Symbol)
+  end
 
-    def mapping &block
-      yield
-    end
+  def mapping &block
+    yield
+  end
 
-    def field hash = {}
-      export_mapping.merge! hash
-    end
+  def field hash
+    @export_mapping.merge! hash
+  end
 
-    def header
-      yield
-    end
+  def file_path string
+    @file_name = string
+  end
 
-    def name value
-      export_header << value
-    end
+  def options hash
+    @csv_options = hash
   end
 end

app/objects/service/line_item_group_exporter.rb

@@ -1,26 +1,32 @@
 require 'exporter'
 
 class LineItemGroupExporter
-  include CSVExporter
+  attr_reader :user, :exporter
 
-  def initialize &block
-    super
+  def initialize user
+    @user = user
   end
 
-  mapping do
-    field 'id' => 'id'
-    field 'article_title' => 'self.articles.last.title'
-  end
+  @exporter = Exporter.new do
+    mapping do
+      field id: 'id'
+      field sold_at: :sold_at
+      field article_title: 'self.articles.last.title'
+      field created_at: ->{ created_at }
+      field hallo: nil
+      field foobar: ''
+      field 'hallo' => 'updated_at'
+    end
 
-  header do
-    name %w(id article_title)
+    file_path "#{ Rails.root }/public/fairmondo_articles.csv"
   end
 
-  def file_name
-    "#{ Rails.root }/public/fairmondo_articles.csv"
+  def export &block
+    @exporter.export(block)
   end
 end
 
+# export { @user.seller_line_item_groups.includes(:business_transactions, :articles, :buyer) }
 
 #  @@csv_options = { col_sep: ";",  encoding: 'utf-8'}
 #