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module ActiveRecord::Sanitization::ClassMethods

Public instance methods

sanitize_sql(condition)

Alias for: sanitize_sql_for_conditions.

sanitize_sql_array(ary)

Accepts an array of conditions. The array has each value sanitized and interpolated into the SQL statement. If using named bind variables in SQL statements where a colon is required verbatim use a backslash to escape.

sanitize_sql_array(["name=? and group_id=?", "foo'bar", 4])
# => "name='foo''bar' and group_id=4"

sanitize_sql_array(["name=:name and group_id=:group_id", name: "foo'bar", group_id: 4])
# => "name='foo''bar' and group_id=4"

sanitize_sql_array(["TO_TIMESTAMP(:date, 'YYYY/MM/DD HH12\\:MI\\:SS')", date: "foo"])
# => "TO_TIMESTAMP('foo', 'YYYY/MM/DD HH12:MI:SS')"

sanitize_sql_array(["name='%s' and group_id='%s'", "foo'bar", 4])
# => "name='foo''bar' and group_id='4'"

Note that this sanitization method is not schema-aware, hence won’t do any type casting and will directly use the database adapter’s quote method. For MySQL specifically this means that numeric parameters will be quoted as strings to prevent query manipulation attacks.

sanitize_sql_array(["role = ?", 0])
# => "role = '0'"

Before using this method, please consider if Arel.sql would be better for your use-case
Source code GitHub 
# File activerecord/lib/active_record/sanitization.rb, line 166
def sanitize_sql_array(ary)
  statement, *values = ary
  if values.first.is_a?(Hash) && /:\w+/.match?(statement)
    with_connection do |c|
      replace_named_bind_variables(c, statement, values.first)
    end
  elsif statement.include?("?")
    with_connection do |c|
      replace_bind_variables(c, statement, values)
    end
  elsif statement.blank?
    statement
  else
    with_connection do |c|
      statement % values.collect { |value| c.quote_string(value.to_s) }
    end
  end
end

sanitize_sql_for_assignment(assignments, default_table_name = table_name)

Accepts an array or hash of SQL conditions and sanitizes them into a valid SQL fragment for a SET clause.

sanitize_sql_for_assignment(["name=? and group_id=?", nil, 4])
# => "name=NULL and group_id=4"

sanitize_sql_for_assignment(["name=:name and group_id=:group_id", name: nil, group_id: 4])
# => "name=NULL and group_id=4"

Post.sanitize_sql_for_assignment({ name: nil, group_id: 4 })
# => "`posts`.`name` = NULL, `posts`.`group_id` = 4"

This method will NOT sanitize an SQL string since it won’t contain any conditions in it and will return the string as is.

sanitize_sql_for_assignment("name=NULL and group_id='4'")
# => "name=NULL and group_id='4'"

Note that this sanitization method is not schema-aware, hence won’t do any type casting and will directly use the database adapter’s quote method. For MySQL specifically this means that numeric parameters will be quoted as strings to prevent query manipulation attacks.

sanitize_sql_for_assignment(["role = ?", 0])
# => "role = '0'"
Source code GitHub 
# File activerecord/lib/active_record/sanitization.rb, line 68
def sanitize_sql_for_assignment(assignments, default_table_name = 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

sanitize_sql_for_conditions(condition)

Also aliased as: sanitize_sql.

Accepts an array of SQL conditions and sanitizes them into a valid SQL fragment for a WHERE clause.

sanitize_sql_for_conditions(["name=? and group_id=?", "foo'bar", 4])
# => "name='foo''bar' and group_id=4"

sanitize_sql_for_conditions(["name=:name and group_id=:group_id", name: "foo'bar", group_id: 4])
# => "name='foo''bar' and group_id='4'"

sanitize_sql_for_conditions(["name='%s' and group_id='%s'", "foo'bar", 4])
# => "name='foo''bar' and group_id='4'"

This method will NOT sanitize an SQL string since it won’t contain any conditions in it and will return the string as is.

sanitize_sql_for_conditions("name='foo''bar' and group_id='4'")
# => "name='foo''bar' and group_id='4'"

Note that this sanitization method is not schema-aware, hence won’t do any type casting and will directly use the database adapter’s quote method. For MySQL specifically this means that numeric parameters will be quoted as strings to prevent query manipulation attacks.

sanitize_sql_for_conditions(["role = ?", 0])
# => "role = '0'"
Source code GitHub 
# File activerecord/lib/active_record/sanitization.rb, line 33
def sanitize_sql_for_conditions(condition)
  return nil if condition.blank?

  case condition
  when Array; sanitize_sql_array(condition)
  else        condition
  end
end

sanitize_sql_for_order(condition)

Accepts an array, or string of SQL conditions and sanitizes them into a valid SQL fragment for an ORDER clause.

sanitize_sql_for_order([Arel.sql("field(id, ?)"), [1,3,2]])
# => "field(id, 1,3,2)"

sanitize_sql_for_order("id ASC")
# => "id ASC"
Source code GitHub 
# File activerecord/lib/active_record/sanitization.rb, line 84
def sanitize_sql_for_order(condition)
  if condition.is_a?(Array) && condition.first.to_s.include?("?")
    disallow_raw_sql!(
      [condition.first],
      permit: adapter_class.column_name_with_order_matcher
    )

    # Ensure we aren't dealing with a subclass of String that might
    # override methods we use (e.g. Arel::Nodes::SqlLiteral).
    if condition.first.kind_of?(String) && !condition.first.instance_of?(String)
      condition = [String.new(condition.first), *condition[1..-1]]
    end

    Arel.sql(sanitize_sql_array(condition))
  else
    condition
  end
end

sanitize_sql_hash_for_assignment(attrs, table)

Sanitizes a hash of attribute/value pairs into SQL conditions for a SET clause.

sanitize_sql_hash_for_assignment({ status: nil, group_id: 1 }, "posts")
# => "`posts`.`status` = NULL, `posts`.`group_id` = 1"
Source code GitHub 
# File activerecord/lib/active_record/sanitization.rb, line 107
def sanitize_sql_hash_for_assignment(attrs, table)
  with_connection do |c|
    attrs.map do |attr, value|
      type = type_for_attribute(attr)
      value = type.serialize(type.cast(value))
      "#{c.quote_table_name_for_assignment(table, attr)} = #{c.quote(value)}"
    end.join(", ")
  end
end

sanitize_sql_like(string, escape_character = "\\")

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 itself, “_” and “%”.

sanitize_sql_like("100% true!")
# => "100\\% true!"

sanitize_sql_like("snake_cased_string")
# => "snake\\_cased\\_string"

sanitize_sql_like("100% true!", "!")
# => "100!% true!!"

sanitize_sql_like("snake_cased_string", "!")
# => "snake!_cased!_string"
Source code GitHub 
# File activerecord/lib/active_record/sanitization.rb, line 132
def sanitize_sql_like(string, escape_character = "\\")
  if string.include?(escape_character) && escape_character != "%" && escape_character != "_"
    string = string.gsub(escape_character, '\0\0')
  end

  string.gsub(/(?=[%_])/, escape_character)
end

Definition files