Log GraphQL-Ruby arguments in their GraphQL format

argument_log.rb

require "bundler/inline"

gemfile do
  gem "graphql", "2.5.6"
  gem "uri"
end

class MySchema < GraphQL::Schema
  class Uri < GraphQL::Schema::Scalar
    def self.coerce_input(value, ctx)
      URI.parse(value)
    end
  end

  class ComplexInput < GraphQL::Schema::InputObject
    argument :id, ID
    argument :float, Float
    argument :uniform_resource_locator, Uri
  end
  class Query < GraphQL::Schema::Object
    field :get_stuff, String, extras: [:ast_node] do
      argument :strs, [String]
      argument :obj, ComplexInput
    end

    def get_stuff(strs:, obj:, ast_node:)
      log_arguments(context, ast_node)
      "OK"
    end
  end

  query(Query)
end

def log_arguments(context, ast_node)
  formatted_args = {}
  ast_node.arguments.each do |argument_node|
    formatted_args[argument_node.name] = format_argument(context, argument_node.value)
  end
  puts "ARGUMENTS:"
  pp formatted_args
end

def format_argument(context, argument_value)
  case argument_value
  when String, Numeric
    argument_value
  when Array
    argument_value.map { |v| format_argument(context, v) }
  when GraphQL::Language::Nodes::InputObject
    args = {}
    argument_value.arguments.each do |arg_node|
      args[arg_node.name] = format_argument(context, arg_node.value)
    end
    args
  when GraphQL::Language::Nodes::VariableIdentifier
    var_value = context.query.variables[argument_value.name]
    formatted = format_argument(context, var_value)
    # You could return one of these or both, depending on your needs:
    {
      variable: "$" + argument_value.name,
      runtime_value: formatted,
    }
  else
    raise ArgumentError, "Unsupported argument value, implement a `when` clause for it: #{argument_value.class} (#{argument_value.class})"
  end
end

pp MySchema.execute(<<~GRAPHQL, variables: { f: 5.67 }).to_h
query ArgTest($world: String = "World", $f: Float!) {
  getStuff(
    strs: ["Hello", $world],
    obj: { id: 123, float: $f, uniformResourceLocator: \"https://graphql-ruby.org\"}
  )
}
GRAPHQL

# ARGUMENTS:
# {"strs" => ["Hello", {variable: "$world", runtime_value: "World"}],
#  "obj" =>
#   {"id" => 123,
#    "float" => {variable: "$f", runtime_value: 5.67},
#    "uniformResourceLocator" => "https://graphql-ruby.org"}}
#
# {"data" => {"getStuff" => "OK"}}