blueprint inside telemetry events comes out as Inspect.Error when in IEx

[MikaAK]

Environment

• Elixir version (elixir -v): 1.13.3
• Absinthe version (mix deps | grep absinthe): 1.7
• Client Framework and version (Relay, Apollo, etc): GraphiQL Interface

Expected behavior

We get the blueprint struct instead of an Inspect.Error

Actual behavior

Inspect.Error on the blueprint field in the [:execute, :operation, :stop] event when using fragments or subscriptions

Relevant Schema/Middleware Code

In an iex shell when printing it out you get

%Inspect.Error{
    message: "got MatchError with message \"no match of right hand side value: %Absinthe.Blueprint{adapter: Absinthe.Adapter.LanguageConventions, directives: [], errors: [], execution: %Absinthe.Blueprint.Execution{...}...
  },

[maartenvanvliet]

I could not reproduce this. Do you have a step by step guide on getting this error?

[kdawgwilk]

This is likely related to another bug but we will need to see a more concrete schema example that reproduces this to narrow it down a bit more

[MikaAK]

I can send a example schema since it happens on any request in our app, just OOO this week but I'll be back in Monday

[aseigo]

Using Elixir 1.15.7 (compiled with Erlang/OTP 26), various errors occur with any schema. For instance, this simple toy schema:

defmodule FSGraphQL.GraphQL.Schema do
  use Absinthe.Schema
  @schema_provider Absinthe.Schema.PersistentTerm
  import_types(Absinthe.Type.Custom)

  def list_features(_, _, _), do: {:ok, []}

  @desc "Metric source types"
  enum :source_type do
    value(:space_area, as: :spacearea, description: "Area")
    value(:metric, as: "Metric", description: "Calculated metric")
  end

  object :branches do
    field :global_id, :string
    field :description, :string
    field :source, :source_type
  end

  input_object :global_id_filter do
    field :global_id, :string
  end

  query do
    field :all_branches, list_of(:branches) do
      arg(:filter, :global_id_filter)
      resolve(&list_features/3)
    end
  end
end

Then inspecting FSGraphQL.GraphQL.Schema.__absinthe_blueprint__ with or without pretty: false results in:

#Inspect.Error<
  got RuntimeError with message:

      """
      Unexpected nil
      """

  while inspecting:
[... schema struct ...]

  Stacktrace:

    (absinthe 1.7.6) lib/absinthe/schema/notation/sdl_render.ex:246: Absinthe.Schema.Notation.SDL.Render.render/2
    (elixir 1.15.7) lib/enum.ex:1693: Enum."-map/2-lists^map/1-1-"/2
    (absinthe 1.7.6) lib/absinthe/schema/notation/sdl_render.ex:51: Absinthe.Schema.Notation.SDL.Render.render/2
    (absinthe 1.7.6) lib/absinthe/schema/notation/sdl_render.ex:12: Absinthe.Schema.Notation.SDL.Render.inspect/2
    (elixir 1.15.7) lib/inspect/algebra.ex:348: Inspect.Algebra.to_doc/2
    (elixir 1.15.7) lib/kernel.ex:2366: Kernel.inspect/2
    (iex 1.15.7) lib/iex/evaluator.ex:375: IEx.Evaluator.io_inspect/1
    (iex 1.15.7) lib/iex/evaluator.ex:334: IEx.Evaluator.eval_and_inspect/3
    (iex 1.15.7) lib/iex/evaluator.ex:305: IEx.Evaluator.eval_and_inspect_parsed/3
    (iex 1.15.7) lib/iex/evaluator.ex:294: IEx.Evaluator.parse_eval_inspect/4
    (iex 1.15.7) lib/iex/evaluator.ex:187: IEx.Evaluator.loop/1
    (iex 1.15.7) lib/iex/evaluator.ex:32: IEx.Evaluator.init/5
    (stdlib 5.1.1) proc_lib.erl:241: :proc_lib.init_p_do_apply/3

Making a Blueprint "by hand" does not render either:

%Absinthe.Blueprint{}

%Absinthe.Blueprint{name: "My Model", schema: FSGraphQL.GraphQL.Schema, schema_definitions: [%Absinthe.Blueprint.Schema.SchemaDefinition{schema_declaration: "MyModel"}]} 

%Absinthe.Blueprint{name: "Urban Model", schema: FSGraphQL.GraphQL.Schema, schema_definitions: [%Absinthe.Blueprint.Schema.SchemaDefinition{schema_declaration: "UrbanModel"}]}

These kick up various errors, including:

#Inspect.Error<
  got MatchError with message:

      """
      no match of right hand side value: %Absinthe.Blueprint{operations: [], directives: [], fragments: [], name: nil, schema_definitions: [], schema: nil, prototype_schema: nil, adapter: nil, initial_phases: [], telemetry: %{}, flags: %{}, errors: [], input: nil, source: nil, execution: %Absinthe.Blueprint.Execution{adapter: nil, schema: nil, fragments: %{}, fields_cache: %{}, validation_errors: [], result: nil, acc: %{}, context: %{}, root_value: %{}}, result: %{}}
      """
>

#Inspect.Error<
  got FunctionClauseError with message:

      """
      no function clause matching in Absinthe.Schema.Notation.SDL.Render.render/2
      """
>

I'm not sure what the expectations are for completeness / setup of these structs, but the renderer seems to fail with default constructions, bare bones manual constructions, and schemas generated from modules. This is true whether or not pretty: true is passed to IO.inspect.

The only reliable way I can see any useful output is to run the struct through Map.from_struct first to bypass the inspect code in Absinthe itself. Annoyingly, doing this on the __asinthe_blueprint__ from a schema module only helps with the top-level Blueprint struct, and the intereior Schema.SchemaDefinition struct will against error out in e.g. SchemaDefition.type_definitions.