feat:Add HTTP support for TxSubmission protocol (#67) (#70)

* Add TxSubmission.HTTP for stateless HTTP transaction operations
* Add HTTP convenience module methods for submit_tx and evaluate_tx
* Add comprehensive test suite with mocks and error handling
* Support transaction submission and evaluation via HTTP
* Include URL parsing and WebSocket-to-HTTP conversion
* Add error handling for CBOR validation, signatures, and UTxO references

* Fix test mock detection order for trigger keywords

Author: rohlacanna

config/test.exs

@@ -2,3 +2,4 @@ import Config
 
 config :xogmios, Xogmios.HealthCheck, http_client: Xogmios.HealthCheck.HTTPClientMock
 config :xogmios, Xogmios.StateQuery.HTTP, http_client: Xogmios.HTTP.ClientMock
+config :xogmios, Xogmios.TxSubmission.HTTP, http_client: Xogmios.HTTP.ClientMock

examples/http_client.ex

@@ -44,10 +44,24 @@ defmodule HTTPClient do
   end
 
   @doc """
-  Demo function showing all HTTP state query operations
+  Submit a transaction via HTTP (stateless)
+  """
+  def submit_transaction(cbor, base_url \\ "http://localhost:1337") do
+    HTTP.submit_tx(base_url, cbor)
+  end
+
+  @doc """
+  Evaluate transaction execution units via HTTP
+  """
+  def evaluate_transaction(cbor, base_url \\ "http://localhost:1337") do
+    HTTP.evaluate_tx(base_url, cbor)
+  end
+
+  @doc """
+  Demo function showing all HTTP operations
   """
   def demo(base_url \\ "http://localhost:1337") do
-    IO.puts("Testing Xogmios HTTP State Queries at #{base_url}")
+    IO.puts("Testing Xogmios HTTP API at #{base_url}")
     IO.puts("")
 
     IO.puts("State Queries:")
@@ -83,6 +97,27 @@ defmodule HTTPClient do
         IO.puts("Protocol parameters error: #{inspect(error)}")
     end
 
+    IO.puts("")
+    IO.puts("Transaction Operations:")
+
+    sample_cbor = "sample_cbor_data_for_demo"
+
+    case submit_transaction(sample_cbor, base_url) do
+      {:ok, %{"transaction" => %{"id" => tx_id}}} ->
+        IO.puts("Transaction submitted: #{tx_id}")
+
+      {:ok, result} ->
+        IO.puts("Transaction result: #{inspect(result)}")
+
+      {:error, error} ->
+        IO.puts("Submit error: #{inspect(error)}")
+    end
+
+    case evaluate_transaction(sample_cbor, base_url) do
+      {:ok, evaluation} -> IO.puts("Evaluation: #{inspect(evaluation)}")
+      {:error, error} -> IO.puts("Evaluation error: #{inspect(error)}")
+    end
+
     IO.puts("")
     IO.puts("Demo completed!")
   end

lib/xogmios/http.ex

@@ -5,7 +5,8 @@ defmodule Xogmios.HTTP do
   This module serves as a unified entry point for users who want to use
   Xogmios in a stateless manner via HTTP instead of WebSocket connections.
   """
-  alias Xogmios.StateQuery.HTTP
+  alias Xogmios.StateQuery
+  alias Xogmios.TxSubmission
 
   @doc """
   Sends a state query via HTTP.
@@ -22,6 +23,36 @@ defmodule Xogmios.HTTP do
   """
   @spec send_query(String.t(), String.t(), map()) :: {:ok, term()} | {:error, term()}
   def send_query(base_url, query, params \\ %{}) do
-    HTTP.send_query(base_url, query, params)
+    StateQuery.HTTP.send_query(base_url, query, params)
+  end
+
+  @doc """
+  Evaluates the execution units of scripts in a transaction via HTTP.
+
+  This function is stateless and doesn't require a running process.
+
+  ## Examples
+
+      iex> Xogmios.HTTP.evaluate_tx("http://localhost:1337", cbor_data)
+      {:ok, %{"evaluation" => %{"script1" => %{"memory" => 1000, "steps" => 500}}}}
+  """
+  @spec evaluate_tx(String.t(), String.t()) :: {:ok, any()} | {:error, any()}
+  def evaluate_tx(base_url, cbor) do
+    TxSubmission.HTTP.evaluate_tx(base_url, cbor)
+  end
+
+  @doc """
+  Submits a transaction via HTTP.
+
+  This function is stateless and doesn't require a running process.
+
+  ## Examples
+
+      iex> Xogmios.HTTP.submit_tx("http://localhost:1337", cbor_data)
+      {:ok, %{"transaction" => %{"id" => "abc123..."}}}
+  """
+  @spec submit_tx(String.t(), String.t()) :: {:ok, any()} | {:error, any()}
+  def submit_tx(base_url, cbor) do
+    TxSubmission.HTTP.submit_tx(base_url, cbor)
   end
 end

lib/xogmios/tx_submission/http.ex

@@ -0,0 +1,100 @@
+defmodule Xogmios.TxSubmission.HTTP do
+  @moduledoc """
+  Stateless HTTP client for Tx Submission protocol.
+
+  This module provides a simpler alternative to the WebSocket-based API
+  for one-off transaction submissions without maintaining persistent connections.
+  """
+
+  alias Xogmios.TxSubmission.Messages
+  alias Xogmios.TxSubmission.Response
+
+  @http_client :httpc
+  @request_timeout 30_000
+
+  @doc """
+  Submits a transaction via HTTP and returns a response including the transaction id.
+
+  This function is stateless and doesn't require a running process.
+  """
+  def submit_tx(base_url, cbor) do
+    url = parse_url(base_url)
+    message = Messages.submit_tx(cbor)
+
+    with {:ok, response_body} <- http_request(url, message),
+         {:ok, %Response{} = response} <- parse_response(response_body) do
+      {:ok, response.result}
+    end
+  end
+
+  @doc """
+  Evaluates the execution units of scripts present in a given transaction.
+
+  This function is stateless and doesn't require a running process.
+  """
+  def evaluate_tx(base_url, cbor) do
+    url = parse_url(base_url)
+    message = Messages.evaluate_tx(cbor)
+
+    with {:ok, response_body} <- http_request(url, message),
+         {:ok, %Response{} = response} <- parse_response(response_body) do
+      {:ok, response.result}
+    end
+  end
+
+  defp parse_url(url) do
+    url
+    |> String.trim_trailing("/")
+    |> replace_protocol()
+  end
+
+  defp replace_protocol(url) do
+    url
+    |> String.replace_prefix("ws://", "http://")
+    |> String.replace_prefix("wss://", "https://")
+  end
+
+  defp http_request(url, message) do
+    headers = [
+      {~c"Content-Type", ~c"application/json"},
+      {~c"Accept", ~c"application/json"}
+    ]
+
+    case client().request(
+           :post,
+           {String.to_charlist(url), headers, ~c"application/json", message},
+           [timeout: @request_timeout],
+           []
+         ) do
+      {:ok, {{_, 200, _}, _headers, body}} ->
+        {:ok, body}
+
+      {:ok, {{_, status_code, _}, _headers, body}} ->
+        {:error, {:http_error, status_code, body}}
+
+      {:error, reason} ->
+        {:error, {:request_failed, reason}}
+    end
+  end
+
+  defp parse_response(body) do
+    case Jason.decode(body) do
+      {:ok, %{"result" => result}} ->
+        {:ok, %Response{result: result}}
+
+      {:ok, %{"error" => error}} ->
+        {:error, error}
+
+      {:ok, unexpected} ->
+        {:error, {:unexpected_response, unexpected}}
+
+      {:error, reason} ->
+        {:error, {:decode_error, reason}}
+    end
+  end
+
+  defp client do
+    Application.get_env(:xogmios, __MODULE__, [])
+    |> Keyword.get(:http_client, @http_client)
+  end
+end