Simpler SeedFu::Writer with revised API and some tests to show it works

lib/seed-fu.rb

@@ -2,11 +2,12 @@
 require 'seed-fu/railtie' if defined?(Rails) && Rails.version >= "3"
 
 module SeedFu
+  autoload :VERSION,               'seed-fu/version'
   autoload :Seeder,                'seed-fu/seeder'
   autoload :ActiveRecordExtension, 'seed-fu/active_record_extension'
   autoload :BlockHash,             'seed-fu/block_hash'
-  autoload :VERSION,               'seed-fu/version'
   autoload :Runner,                'seed-fu/runner'
+  autoload :Writer,                'seed-fu/writer'
 
   # Turn off the output when seeding data
   mattr_accessor :quiet

lib/seed-fu/railtie.rb

@@ -0,0 +1,14 @@
+module SeedFu
+  class Railtie < Rails::Railtie
+    rake_tasks do
+      load "tasks/seed_fu.rake"
+    end
+
+    initializer 'seed_fu.set_fixture_paths' do
+      SeedFu.fixture_paths = [
+        Rails.root.join('db/fixtures').to_s,
+        Rails.root.join('db/fixtures/' + Rails.env).to_s
+      ]
+    end
+  end
+end

lib/seed-fu/writer.rb

@@ -1,3 +1,90 @@
-require File.join( File.dirname(__FILE__), 'writer', 'abstract' )
-require File.join( File.dirname(__FILE__), 'writer', 'seed' )
-require File.join( File.dirname(__FILE__), 'writer', 'seed_many' )
+module SeedFu
+  class Writer
+    def initialize(options = {})
+      @options = options
+      @options[:chunk_size]  ||= 100
+      @options[:constraints] ||= [:id]
+
+      raise ArgumentError, "missing option :class_name" unless @options[:class_name]
+    end
+
+    def self.write(io_or_filename, options = {}, &block)
+      new(options).write(io_or_filename, &block)
+    end
+
+    def write(io_or_filename, &block)
+      if io_or_filename.respond_to?(:write)
+        write_to_io(io_or_filename, &block)
+      else
+        File.open(io_or_filename, 'w') do |file|
+          write_to_io(file, &block)
+        end
+      end
+    end
+
+    def <<(seed)
+      raise "You must add seeds inside a SeedFu::Writer#write block" unless @io
+
+      buffer = ''
+
+      if chunk_this_seed?
+        buffer << seed_footer
+        buffer << "# BREAK EVAL\n"
+        buffer << seed_header
+      end
+
+      buffer << ",\n"
+      buffer << '  ' + seed.inspect
+
+      @io.write(buffer)
+
+      @count += 1
+    end
+    alias_method :add, :<<
+
+    private
+
+      def write_to_io(io)
+        @io, @count = io, 0
+        @io.write(file_header)
+        @io.write(seed_header)
+        yield(self)
+        @io.write(seed_footer)
+        @io.write(file_footer)
+      ensure
+        @io, @count = nil, nil
+      end
+
+      def file_header
+        <<-END
+# DO NOT MODIFY THIS FILE, it was auto-generated.
+#
+# Date: #{Time.now}
+# Seeding #{@options[:class_name]}
+# Written with the command:
+#
+#   #{$0} #{$*.join}
+#
+        END
+      end
+
+      def file_footer
+        <<-END
+# End auto-generated file.
+        END
+      end
+
+      def seed_header
+        constraints = @options[:constraints] && @options[:constraints].map(&:inspect).join(', ')
+        "#{@options[:class_name]}.seed(#{constraints}"
+      end
+
+      def seed_footer
+        "\n)\n"
+      end
+
+      def chunk_this_seed?
+        @count != 0 && (@count % @options[:chunk_size]) == 0
+      end
+  end
+end

spec/runner_spec.rb

@@ -0,0 +1,24 @@
+require 'spec_helper'
+
+describe SeedFu::Runner do
+  it "should seed data from Ruby and gzipped Ruby files in the given fixtures directory" do
+    SeedFu.seed(File.dirname(__FILE__) + '/fixtures')
+
+    SeededModel.find(1).title.should == "Foo"
+    SeededModel.find(2).title.should == "Bar"
+    SeededModel.find(3).title.should == "Baz"
+  end
+
+  it "should seed only the data which matches the filter, if one is given" do
+    SeedFu.seed(File.dirname(__FILE__) + '/fixtures', /_2/)
+
+    SeededModel.count.should == 1
+    SeededModel.find(2).title.should == "Bar"
+  end
+
+  it "should use the SpecFu.fixtures_path variable to determine where fixtures are" do
+    SeedFu.fixture_paths = [File.dirname(__FILE__) + '/fixtures']
+    SeedFu.seed
+    SeededModel.count.should == 3
+  end
+end

spec/seed_fu_spec.rb → spec/seeder_spec.rb

@@ -1,10 +1,6 @@
 require 'spec_helper'
 
 describe SeedFu::Seeder do
-  before do
-    SeededModel.delete_all
-  end
-
   it "should create a model if one doesn't exist" do
     SeededModel.seed(:id) do |s|
       s.id = 5
@@ -132,25 +128,4 @@
   it "should raise an error if validation fails" do
     lambda { SeededModel.seed(:id => 1) }.should raise_error(ActiveRecord::RecordInvalid)
   end
-
-  it "should seed data from Ruby and gzipped Ruby files in the given fixtures directory" do
-    SeedFu.seed(File.dirname(__FILE__) + '/fixtures')
-
-    SeededModel.find(1).title.should == "Foo"
-    SeededModel.find(2).title.should == "Bar"
-    SeededModel.find(3).title.should == "Baz"
-  end
-
-  it "should seed only the data which matches the filter, if one is given" do
-    SeedFu.seed(File.dirname(__FILE__) + '/fixtures', /_2/)
-
-    SeededModel.count.should == 1
-    SeededModel.find(2).title.should == "Bar"
-  end
-
-  it "should use the SpecFu.fixtures_path variable to determine where fixtures are" do
-    SeedFu.fixture_paths = [File.dirname(__FILE__) + '/fixtures']
-    SeedFu.seed
-    SeededModel.count.should == 3
-  end
 end

spec/spec_helper.rb

@@ -3,6 +3,12 @@
 require 'seed-fu'
 require 'logger'
 
+RSpec.configure do |config|
+  config.before do
+    SeededModel.delete_all
+  end
+end
+
 SeedFu.quiet = true
 
 ActiveRecord::Base.logger = Logger.new(File.dirname(__FILE__) + "/../debug.log")

spec/writer_spec.rb

@@ -0,0 +1,36 @@
+require 'spec_helper'
+
+describe SeedFu::Writer do
+  before do
+    @file_name = File.dirname(__FILE__) + '/seeded_models.rb'
+  end
+
+  after do
+    FileUtils.rm(@file_name)
+  end
+
+  it "should successfully write some seeds out to a file and then import them back in" do
+    SeedFu::Writer.write(@file_name, :class_name => 'SeededModel') do |writer|
+      writer << { :id => 1, :title => "Mr" }
+      writer << { :id => 2, :title => "Dr" }
+    end
+
+    load @file_name
+
+    SeededModel.find(1).title.should == "Mr"
+    SeededModel.find(2).title.should == "Dr"
+  end
+
+  it "should support chunking" do
+    SeedFu::Writer.write(@file_name, :class_name => 'SeededModel', :chunk_size => 2) do |writer|
+      writer << { :id => 1, :title => "Mr" }
+      writer << { :id => 2, :title => "Dr" }
+      writer << { :id => 3, :title => "Dr" }
+    end
+
+    load @file_name
+
+    SeededModel.count.should == 3
+    File.read(@file_name).should include("# BREAK EVAL\n")
+  end
+end