aboutsummaryrefslogtreecommitdiffstats
path: root/activerecord/lib/active_record/schema_dumper.rb
blob: 2bbfd016981e709634f56c35734ce56ed89206dd (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
require "stringio"

module ActiveRecord
  # = Active Record Schema Dumper
  #
  # This class is used to dump the database schema for some connection to some
  # output format (i.e., ActiveRecord::Schema).
  class SchemaDumper #:nodoc:
    private_class_method :new

    ##
    # :singleton-method:
    # A list of tables which should not be dumped to the schema.
    # Acceptable values are strings as well as regexp.
    # This setting is only used if ActiveRecord::Base.schema_format == :ruby
    cattr_accessor :ignore_tables
    @@ignore_tables = []

    class << self
      def dump(connection = ActiveRecord::Base.connection, stream = STDOUT, config = ActiveRecord::Base)
        new(connection, generate_options(config)).dump(stream)
        stream
      end

      private
        def generate_options(config)
          {
            table_name_prefix: config.table_name_prefix,
            table_name_suffix: config.table_name_suffix
          }
        end
    end

    def dump(stream)
      header(stream)
      extensions(stream)
      tables(stream)
      trailer(stream)
      stream
    end

    private

      def initialize(connection, options = {})
        @connection = connection
        @version = Migrator::current_version rescue nil
        @options = options
      end

      def header(stream)
        define_params = @version ? "version: #{@version}" : ""

        stream.puts <<HEADER
# This file is auto-generated from the current state of the database. Instead
# of editing this file, please use the migrations feature of Active Record to
# incrementally modify your database, and then regenerate this schema definition.
#
# Note that this schema.rb definition is the authoritative source for your
# database schema. If you need to create the application database on another
# system, you should be using db:schema:load, not running all the migrations
# from scratch. The latter is a flawed and unsustainable approach (the more migrations
# you'll amass, the slower it'll run and the greater likelihood for issues).
#
# It's strongly recommended that you check this file into your version control system.

ActiveRecord::Schema.define(#{define_params}) do

HEADER
      end

      def trailer(stream)
        stream.puts "end"
      end

      def extensions(stream)
        return unless @connection.supports_extensions?
        extensions = @connection.extensions
        if extensions.any?
          stream.puts "  # These are extensions that must be enabled in order to support this database"
          extensions.each do |extension|
            stream.puts "  enable_extension #{extension.inspect}"
          end
          stream.puts
        end
      end

      def tables(stream)
        sorted_tables = @connection.tables.sort

        sorted_tables.each do |table_name|
          table(table_name, stream) unless ignored?(table_name)
        end

        # dump foreign keys at the end to make sure all dependent tables exist.
        if @connection.supports_foreign_keys?
          sorted_tables.each do |tbl|
            foreign_keys(tbl, stream) unless ignored?(tbl)
          end
        end
      end

      def table(table, stream)
        columns = @connection.columns(table)
        begin
          tbl = StringIO.new

          # first dump primary key column
          pk = @connection.primary_key(table)

          tbl.print "  create_table #{remove_prefix_and_suffix(table).inspect}"

          case pk
          when String
            tbl.print ", primary_key: #{pk.inspect}" unless pk == "id"
            pkcol = columns.detect { |c| c.name == pk }
            pkcolspec = @connection.column_spec_for_primary_key(pkcol)
            if pkcolspec.present?
              tbl.print ", #{format_colspec(pkcolspec)}"
            end
          when Array
            tbl.print ", primary_key: #{pk.inspect}"
          else
            tbl.print ", id: false"
          end
          tbl.print ", force: :cascade"

          table_options = @connection.table_options(table)
          if table_options.present?
            tbl.print ", #{format_options(table_options)}"
          end

          tbl.puts " do |t|"

          # then dump all non-primary key columns
          columns.each do |column|
            raise StandardError, "Unknown type '#{column.sql_type}' for column '#{column.name}'" unless @connection.valid_type?(column.type)
            next if column.name == pk
            type, colspec = @connection.column_spec(column)
            tbl.print "    t.#{type} #{column.name.inspect}"
            tbl.print ", #{format_colspec(colspec)}" if colspec.present?
            tbl.puts
          end

          indexes_in_create(table, tbl)

          tbl.puts "  end"
          tbl.puts

          tbl.rewind
          stream.print tbl.read
        rescue => e
          stream.puts "# Could not dump table #{table.inspect} because of following #{e.class}"
          stream.puts "#   #{e.message}"
          stream.puts
        end

        stream
      end

      # Keep it for indexing materialized views
      def indexes(table, stream)
        if (indexes = @connection.indexes(table)).any?
          add_index_statements = indexes.map do |index|
            table_name = remove_prefix_and_suffix(index.table).inspect
            "  add_index #{([table_name] + index_parts(index)).join(', ')}"
          end

          stream.puts add_index_statements.sort.join("\n")
          stream.puts
        end
      end

      def indexes_in_create(table, stream)
        if (indexes = @connection.indexes(table)).any?
          index_statements = indexes.map do |index|
            "    t.index #{index_parts(index).join(', ')}"
          end
          stream.puts index_statements.sort.join("\n")
        end
      end

      def index_parts(index)
        index_parts = [
          index.columns.inspect,
          "name: #{index.name.inspect}",
        ]
        index_parts << "unique: true" if index.unique
        index_parts << "length: { #{format_options(index.lengths)} }" if index.lengths.present?
        index_parts << "order: { #{format_options(index.orders)} }" if index.orders.present?
        index_parts << "where: #{index.where.inspect}" if index.where
        index_parts << "using: #{index.using.inspect}" if !@connection.default_index_type?(index)
        index_parts << "type: #{index.type.inspect}" if index.type
        index_parts << "comment: #{index.comment.inspect}" if index.comment
        index_parts
      end

      def foreign_keys(table, stream)
        if (foreign_keys = @connection.foreign_keys(table)).any?
          add_foreign_key_statements = foreign_keys.map do |foreign_key|
            parts = [
              "add_foreign_key #{remove_prefix_and_suffix(foreign_key.from_table).inspect}",
              remove_prefix_and_suffix(foreign_key.to_table).inspect,
            ]

            if foreign_key.column != @connection.foreign_key_column_for(foreign_key.to_table)
              parts << "column: #{foreign_key.column.inspect}"
            end

            if foreign_key.custom_primary_key?
              parts << "primary_key: #{foreign_key.primary_key.inspect}"
            end

            if foreign_key.name !~ /^fk_rails_[0-9a-f]{10}$/
              parts << "name: #{foreign_key.name.inspect}"
            end

            parts << "on_update: #{foreign_key.on_update.inspect}" if foreign_key.on_update
            parts << "on_delete: #{foreign_key.on_delete.inspect}" if foreign_key.on_delete

            "  #{parts.join(', ')}"
          end

          stream.puts add_foreign_key_statements.sort.join("\n")
        end
      end

      def format_colspec(colspec)
        colspec.map { |key, value| "#{key}: #{value}" }.join(", ")
      end

      def format_options(options)
        options.map { |key, value| "#{key}: #{value.inspect}" }.join(", ")
      end

      def remove_prefix_and_suffix(table)
        table.gsub(/^(#{@options[:table_name_prefix]})(.+)(#{@options[:table_name_suffix]})$/,  "\\2")
      end

      def ignored?(table_name)
        [ActiveRecord::Base.schema_migrations_table_name, ActiveRecord::Base.internal_metadata_table_name, ignore_tables].flatten.any? do |ignored|
          ignored === remove_prefix_and_suffix(table_name)
        end
      end
  end
end