chore: removes a not so necessary function

Author: Adriano Santos

examples/helloworld_streams/lib/helloworld_streams/server.ex

@@ -22,12 +22,8 @@ defmodule HelloworldStreams.Server do
 
   @spec say_server_hello(HelloRequest.t(), GRPC.Server.Stream.t()) :: any()
   def say_server_hello(request, materializer) do
-    GRPCStream.unary(request, propagate_context: true, materializer: materializer)
-    # Create new output stream from the request and drop the input
-    |> GRPCStream.via(fn _metadata, %HelloRequest{} = msg ->
-      create_output_stream(msg)
-      |> GRPCStream.from()
-    end)
+    create_output_stream(request)
+    |> GRPCStream.from()
     |> GRPCStream.run_with(materializer)
   end
 

lib/grpc/stream.ex

@@ -233,42 +233,6 @@ defmodule GRPC.Stream do
   @spec ask!(t(), pid | atom, non_neg_integer) :: t()
   defdelegate ask!(stream, target, timeout \\ 5000), to: Operators
 
-  @doc """
-  Replaces the current stream with a new one generated by the given factory function.
-  The factory function receives the metadata and the current item as arguments.
-  The factory function returns a new `GRPC.Stream` struct.
-
-  ## Behavior
-  Materializes the left stream by passing the first element to the right stream. Useful when used with single/2 to dynamically create a new output stream.
-
-  ## Caution
-
-  This function materializes the current stream and replaces it with a new one.
-  This can lead to performance issues if used excessively. In fact, it is more commonly used
-  in following the `single/2` function. 
-
-  ## Parameters
-
-    - `stream`: The current `GRPC.Stream`.
-    - `factory`: A function that takes metadata and the current item, returning a new `GRPC.Stream`.
-
-  ## Returns
-    - A new `GRPC.Stream` struct with the replaced flow.
-
-  ## Example
-
-    GRPC.Stream.single(request)
-    # Create new output stream from the request and drop the input
-    |> GRPC.Stream.via(fn _metadata, msg ->
-      create_output_stream(msg) # returns some Enumerable
-      |> GRPC.Stream.from()
-    end)
-    |> GRPC.Stream.run_with(materializer)
-    
-  """
-  @spec via(t(), (map(), term -> term)) :: t()
-  defdelegate via(stream, factory), to: Operators
-
   @doc """
   Filters the stream using the given predicate function.
 

lib/grpc/stream/operators.ex

@@ -51,25 +51,6 @@ defmodule GRPC.Stream.Operators do
     end
   end
 
-  @spec via(GRPCStream.t(), (map(), term -> term)) :: GRPCStream.t()
-  def via(%GRPCStream{flow: flow, metadata: metadata} = _stream, factory)
-      when is_function(factory, 2) do
-    new =
-      Flow.map(flow, fn item ->
-        case factory.(metadata, item) do
-          %GRPCStream{} = stream ->
-            %GRPCStream{stream | metadata: metadata}
-
-          _ ->
-            raise ArgumentError, "Expected factory to return a GRPC.Stream"
-        end
-      end)
-      |> Enum.to_list()
-      |> Enum.at(0)
-
-    %GRPCStream{new | flow: new.flow, metadata: new.metadata, options: new.options}
-  end
-
   @spec filter(GRPCStream.t(), (term -> term)) :: GRPCStream.t()
   def filter(%GRPCStream{flow: flow} = stream, filter) do
     %GRPCStream{stream | flow: Flow.filter(flow, filter)}