zf

zenflows testing
git clone https://s.sonu.ch/~srfsh/zf.git
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dataloader.ex (1533B)

      1 if Code.ensure_loaded?(Dataloader) do
      2   defmodule Absinthe.Middleware.Dataloader do
      3     @behaviour Absinthe.Middleware
      4     @behaviour Absinthe.Plugin
      5 
      6     @impl Absinthe.Plugin
      7     def before_resolution(%{context: context} = exec) do
      8       context =
      9         with %{loader: loader} <- context do
     10           %{context | loader: Dataloader.run(loader)}
     11         end
     12 
     13       %{exec | context: context}
     14     end
     15 
     16     @impl Absinthe.Middleware
     17     def call(%{state: :unresolved} = resolution, {loader, callback}) do
     18       if !Dataloader.pending_batches?(loader) do
     19         resolution.context.loader
     20         |> put_in(loader)
     21         |> get_result(callback)
     22       else
     23         %{
     24           resolution
     25           | context: Map.put(resolution.context, :loader, loader),
     26             state: :suspended,
     27             middleware: [{__MODULE__, callback} | resolution.middleware]
     28         }
     29       end
     30     end
     31 
     32     def call(%{state: :suspended} = resolution, callback) do
     33       get_result(resolution, callback)
     34     end
     35 
     36     defp get_result(resolution, callback) do
     37       value = callback.(resolution.context.loader)
     38       Absinthe.Resolution.put_result(resolution, value)
     39     end
     40 
     41     @impl Absinthe.Plugin
     42     def after_resolution(exec) do
     43       exec
     44     end
     45 
     46     @impl Absinthe.Plugin
     47     def pipeline(pipeline, exec) do
     48       with %{loader: loader} <- exec.context,
     49            true <- Dataloader.pending_batches?(loader) do
     50         [Absinthe.Phase.Document.Execution.Resolution | pipeline]
     51       else
     52         _ -> pipeline
     53       end
     54     end
     55   end
     56 end