Contents

# frozen_string_literal: true
module GraphQL
  class Query
    # Read-only access to query variables, applying default values if needed.
    class Variables
      extend Forwardable

      # @return [Array<GraphQL::Query::VariableValidationError>]  Any errors encountered when parsing the provided variables and literal values
      attr_reader :errors

      def initialize(schema, warden, ast_variables, provided_variables)
        @schema = schema
        @warden = warden
        @provided_variables = provided_variables
        @errors = []
        @storage = ast_variables.each_with_object({}) do |ast_variable, memo|
          # Find the right value for this variable:
          # - First, use the value provided at runtime
          # - Then, fall back to the default value from the query string
          # If it's still nil, raise an error if it's required.
          variable_type = @schema.type_from_ast(ast_variable.type)
          variable_name = ast_variable.name
          default_value = ast_variable.default_value
          provided_value = @provided_variables[variable_name]
          value_was_provided = @provided_variables.key?(variable_name)

          validation_result = variable_type.validate_input(provided_value, @warden)
          if !validation_result.valid?
            # This finds variables that were required but not provided
            @errors << GraphQL::Query::VariableValidationError.new(ast_variable, variable_type, provided_value, validation_result)
          elsif value_was_provided
            # Add the variable if a value was provided
            memo[variable_name] = variable_type.coerce_input(provided_value)
          elsif default_value
            # Add the variable if it wasn't provided but it has a default value (including `null`)
            memo[variable_name] = GraphQL::Query::LiteralInput.coerce(variable_type, default_value, {})
          end
        end
      end

      def_delegators :@storage, :length, :key?, :[], :fetch
    end
  end
end

Version data entries

6 entries across 6 versions & 1 rubygems

Version	Path
graphql-1.5.3	lib/graphql/query/variables.rb
graphql-1.4.5	lib/graphql/query/variables.rb
graphql-1.4.4	lib/graphql/query/variables.rb
graphql-1.4.3	lib/graphql/query/variables.rb
graphql-1.4.2	lib/graphql/query/variables.rb
graphql-1.4.1	lib/graphql/query/variables.rb