lib/nullalign.rb in nullalign-0.0.2 vs lib/nullalign.rb in nullalign-0.0.3

@@ -1,9 +1,10 @@
 require 'nullalign/models'
 require 'nullalign/introspectors/table_data'
 require 'nullalign/introspectors/validates_presence_of'
 require 'nullalign/reporter'
+require 'nullalign/railtie'
 
 module Nullalign
   def self.run
     models = Nullalign::Models.new($LOAD_PATH)
     models.preload_all
@@ -13,16 +14,47 @@
     introspector = Nullalign::Introspectors::ValidatesPresenceOf.new
     problems = problems(models.all, introspector)
     reporter.report_validates_presence_problems(problems)
     problems.empty?
   end
-  
+
+  def self.generate_migration
+    models = Nullalign::Models.new($LOAD_PATH)
+    models.preload_all
+
+    reporter = Nullalign::Reporter.new
+
+    introspector = Nullalign::Introspectors::ValidatesPresenceOf.new
+    problems = problems(models.all, introspector)
+    if problems.empty?
+      puts "Hooray! All presence validators are backed by a non-null constraint."
+    else
+      str = "class AddMissingNonnullConstraints < ActiveRecord::Migration[5.1]\n"
+      str << "  def change\n"
+      null_constraints_by_table_name = problems.map do |model, columns|
+        [model.name, model, columns]
+      end.sort_by(&:first)
+      counter = 0
+      null_constraints_by_table_name.each do |table_name, model, columns|
+        columns.each do |constraint|
+          counter += 1
+          str << "    change_column_null :#{model.table_name}, :#{constraint.column}, false\n"
+        end
+      end
+      str << "  end\n"
+      str << "end\n"
+      filename = "db/migrate/#{Time.now.utc.strftime("%Y%m%d%H%M%S")}_add_missing_nonnull_constraints.rb"
+      puts "Adding migration #{File.basename(filename)} containing #{counter} change_column_null entries"
+      File.open(filename, "w") {|f| f.syswrite(str)}
+    end
+  end
+
   private
-  
+
   def self.problems(models, introspector)
     models.map do |m|
       [m, introspector.missing_nonnull_constraints(m)]
     end.reject do |m, columns|
       columns.empty?
     end
   end
-end
\ No newline at end of file
+end