aboutsummaryrefslogtreecommitdiffstats
path: root/activerecord/lib/active_record/database_configurations.rb
blob: a94f46d07f5f027b8847d5485017177470d470de (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
# frozen_string_literal: true

require "active_record/database_configurations/database_config"
require "active_record/database_configurations/hash_config"
require "active_record/database_configurations/url_config"

module ActiveRecord
  # ActiveRecord::DatabaseConfigurations returns an array of DatabaseConfig
  # objects (either a HashConfig or UrlConfig) that are constructed from the
  # application's database configuration hash or url string.
  class DatabaseConfigurations
    attr_reader :configurations

    def initialize(configurations = {})
      @configurations = build_configs(configurations)
    end

    # Collects the configs for the environment and optionally the specification
    # name passed in. To include replica configurations pass `include_replicas: true`.
    #
    # If a spec name is provided a single DatabaseConfiguration object will be
    # returned, otherwise an array of DatabaseConfiguration objects will be
    # returned that corresponds with the environment and type requested.
    #
    # Options:
    #
    # <tt>env_name:</tt> The environment name. Defaults to nil which will collect
    # configs for all environments.
    # <tt>spec_name:</tt> The specification name (ie primary, animals, etc.). Defaults
    # to +nil+.
    # <tt>include_replicas:</tt> Determines whether to include replicas in the
    # the returned list. Most of the time we're only iterating over the write
    # connection (i.e. migrations don't need to run for the write and read connection).
    # Defaults to +false+.
    def configs_for(env_name: nil, spec_name: nil, include_replicas: false)
      configs = env_with_configs(env_name)

      unless include_replicas
        configs = configs.select do |db_config|
          !db_config.replica?
        end
      end

      if spec_name
        configs.find do |db_config|
          db_config.spec_name == spec_name
        end
      else
        configs
      end
    end

    # Returns the config hash that corresponds with the environment
    #
    # If the application has multiple databases `default_hash` will
    # the first config hash for the environment.
    #
    #   { database: "my_db", adapter: "mysql2" }
    def default_hash(env = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call.to_s)
      default = find_db_config(env)
      default.config if default
    end
    alias :[] :default_hash

    # Returns a single DatabaseConfig object based on the requested environment.
    #
    # If the application has multiple databases `select_db_config` will return
    # the first DatabaseConfig for the environment.
    def find_db_config(env)
      configurations.find do |db_config|
        db_config.env_name == env.to_s ||
          (db_config.for_current_env? && db_config.spec_name == env.to_s)
      end
    end

    # Returns the DatabaseConfig object as a Hash.
    def to_h
      configs = configurations.reverse.inject({}) do |memo, db_config|
        memo.merge(db_config.to_legacy_hash)
      end

      Hash[configs.to_a.reverse]
    end

    # Checks if the application's configurations are empty.
    #
    # Aliased to blank?
    def empty?
      configurations.empty?
    end
    alias :blank? :empty?

    private
      def env_with_configs(env = nil)
        if env
          configurations.select { |db_config| db_config.env_name == env }
        else
          configurations
        end
      end

      def build_configs(configs)
        return configs.configurations if configs.is_a?(DatabaseConfigurations)

        build_db_config = configs.each_pair.flat_map do |env_name, config|
          walk_configs(env_name, "primary", config)
        end.compact

        if url = ENV["DATABASE_URL"]
          build_url_config(url, build_db_config)
        else
          build_db_config
        end
      end

      def walk_configs(env_name, spec_name, config)
        case config
        when String
          build_db_config_from_string(env_name, spec_name, config)
        when Hash
          build_db_config_from_hash(env_name, spec_name, config)
        end
      end

      def build_db_config_from_string(env_name, spec_name, config)
        begin
          url = config
          uri = URI.parse(url)
          if uri.try(:scheme)
            ActiveRecord::DatabaseConfigurations::UrlConfig.new(env_name, spec_name, url)
          end
        rescue URI::InvalidURIError
          ActiveRecord::DatabaseConfigurations::HashConfig.new(env_name, spec_name, config)
        end
      end

      def build_db_config_from_hash(env_name, spec_name, config)
        if url = config["url"]
          config_without_url = config.dup
          config_without_url.delete "url"
          ActiveRecord::DatabaseConfigurations::UrlConfig.new(env_name, spec_name, url, config_without_url)
        elsif config["database"] || (config.size == 1 && config.values.all? { |v| v.is_a? String })
          ActiveRecord::DatabaseConfigurations::HashConfig.new(env_name, spec_name, config)
        else
          config.each_pair.map do |sub_spec_name, sub_config|
            walk_configs(env_name, sub_spec_name, sub_config)
          end
        end
      end

      def build_url_config(url, configs)
        env = ActiveRecord::ConnectionHandling::DEFAULT_ENV.call.to_s

        if original_config = configs.find(&:for_current_env?)
          if original_config.url_config?
            configs
          else
            configs.map do |config|
              ActiveRecord::DatabaseConfigurations::UrlConfig.new(env, config.spec_name, url, config.config)
            end
          end
        else
          configs + [ActiveRecord::DatabaseConfigurations::UrlConfig.new(env, "primary", url)]
        end
      end

      def method_missing(method, *args, &blk)
        if Hash.method_defined?(method)
          ActiveSupport::Deprecation.warn \
            "Returning a hash from ActiveRecord::Base.configurations is deprecated. Therefore calling `#{method}` on the hash is also deprecated. Please switch to using the `configs_for` method instead to collect and iterate over database configurations."
        end

        case method
        when :each, :first
          configurations.send(method, *args, &blk)
        when :fetch
          configs_for(env_name: args.first)
        when :values
          configurations.map(&:config)
        else
          super
        end
      end
  end
end