aboutsummaryrefslogtreecommitdiffstats
path: root/activerecord/lib/active_record/sanitization.rb
blob: 32f42299773e19976099d4967a04c6f64636c7a1 (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
module ActiveRecord
  module Sanitization
    extend ActiveSupport::Concern

    module ClassMethods
      # Used to sanitize objects before they're used in an SQL SELECT statement. Delegates to <tt>connection.quote</tt>.
      def sanitize(object) #:nodoc:
        connection.quote(object)
      end
      alias_method :quote_value, :sanitize

      protected

      # Accepts an array or string of SQL conditions and sanitizes
      # them into a valid SQL fragment for a WHERE clause.
      #   ["name='%s' and group_id='%s'", "foo'bar", 4]  returns  "name='foo''bar' and group_id='4'"
      #   "name='foo''bar' and group_id='4'" returns "name='foo''bar' and group_id='4'"
      def sanitize_sql_for_conditions(condition)
        return nil if condition.blank?

        case condition
        when Array; sanitize_sql_array(condition)
        else        condition
        end
      end
      alias_method :sanitize_sql, :sanitize_sql_for_conditions
      alias_method :sanitize_conditions, :sanitize_sql

      # Accepts an array, hash, or string of SQL conditions and sanitizes
      # them into a valid SQL fragment for a SET clause.
      #   { name: nil, group_id: 4 }  returns "name = NULL , group_id='4'"
      def sanitize_sql_for_assignment(assignments, default_table_name = self.table_name)
        case assignments
        when Array; sanitize_sql_array(assignments)
        when Hash;  sanitize_sql_hash_for_assignment(assignments, default_table_name)
        else        assignments
        end
      end

      # Accepts a hash of SQL conditions and replaces those attributes
      # that correspond to a +composed_of+ relationship with their expanded
      # aggregate attribute values.
      # Given:
      #     class Person < ActiveRecord::Base
      #       composed_of :address, class_name: "Address",
      #         mapping: [%w(address_street street), %w(address_city city)]
      #     end
      # Then:
      #     { address: Address.new("813 abc st.", "chicago") }
      #       # => { address_street: "813 abc st.", address_city: "chicago" }
      def expand_hash_conditions_for_aggregates(attrs)
        expanded_attrs = {}
        attrs.each do |attr, value|
          if aggregation = reflect_on_aggregation(attr.to_sym)
            mapping = aggregation.mapping
            mapping.each do |field_attr, aggregate_attr|
              if mapping.size == 1 && !value.respond_to?(aggregate_attr)
                expanded_attrs[field_attr] = value
              else
                expanded_attrs[field_attr] = value.send(aggregate_attr)
              end
            end
          else
            expanded_attrs[attr] = value
          end
        end
        expanded_attrs
      end

      # Sanitizes a hash of attribute/value pairs into SQL conditions for a SET clause.
      #   { status: nil, group_id: 1 }
      #     # => "status = NULL , group_id = 1"
      def sanitize_sql_hash_for_assignment(attrs, table)
        c = connection
        attrs.map do |attr, value|
          value = type_for_attribute(attr.to_s).serialize(value)
          "#{c.quote_table_name_for_assignment(table, attr)} = #{c.quote(value)}"
        end.join(', ')
      end

      # Sanitizes a +string+ so that it is safe to use within an SQL
      # LIKE statement. This method uses +escape_character+ to escape all occurrences of "\", "_" and "%"
      def sanitize_sql_like(string, escape_character = "\\")
        pattern = Regexp.union(escape_character, "%", "_")
        string.gsub(pattern) { |x| [escape_character, x].join }
      end

      # Accepts an array of conditions. The array has each value
      # sanitized and interpolated into the SQL statement.
      #   ["name='%s' and group_id='%s'", "foo'bar", 4]  returns  "name='foo''bar' and group_id='4'"
      def sanitize_sql_array(ary)
        statement, *values = ary
        if values.first.is_a?(Hash) && statement =~ /:\w+/
          replace_named_bind_variables(statement, values.first)
        elsif statement.include?('?')
          replace_bind_variables(statement, values)
        elsif statement.blank?
          statement
        else
          statement % values.collect { |value| connection.quote_string(value.to_s) }
        end
      end

      def replace_bind_variables(statement, values) #:nodoc:
        raise_if_bind_arity_mismatch(statement, statement.count('?'), values.size)
        bound = values.dup
        c = connection
        statement.gsub(/\?/) do
          replace_bind_variable(bound.shift, c)
        end
      end

      def replace_bind_variable(value, c = connection) #:nodoc:
        if ActiveRecord::Relation === value
          value.to_sql
        else
          quote_bound_value(value, c)
        end
      end

      def replace_named_bind_variables(statement, bind_vars) #:nodoc:
        statement.gsub(/(:?):([a-zA-Z]\w*)/) do |match|
          if $1 == ':' # skip postgresql casts
            match # return the whole match
          elsif bind_vars.include?(match = $2.to_sym)
            replace_bind_variable(bind_vars[match])
          else
            raise PreparedStatementInvalid, "missing value for :#{match} in #{statement}"
          end
        end
      end

      def quote_bound_value(value, c = connection) #:nodoc:
        if value.respond_to?(:map) && !value.acts_like?(:string)
          if value.respond_to?(:empty?) && value.empty?
            c.quote(nil)
          else
            value.map { |v| c.quote(v) }.join(',')
          end
        else
          c.quote(value)
        end
      end

      def raise_if_bind_arity_mismatch(statement, expected, provided) #:nodoc:
        unless expected == provided
          raise PreparedStatementInvalid, "wrong number of bind variables (#{provided} for #{expected}) in: #{statement}"
        end
      end
    end

    # TODO: Deprecate this
    def quoted_id
      self.class.quote_value(@attributes[self.class.primary_key].value_for_database)
    end
  end
end