Add generic request method

CHANGELOG.md

@@ -0,0 +1,5 @@
+# 0.1.2
+* Added generic request method
+
+# 0.1.1
+* Added necessary JSON header for parity

README.md

@@ -8,7 +8,7 @@ Add Ethereumex to your `mix.exs` dependencies:
 1. Add `ethereumex` to your list of dependencies in `mix.exs`:
 ```elixir
 def deps do
-  [{:ethereumex, "~> 0.1.0"}]
+  [{:ethereumex, "~> 0.1.2"}]
 end
 ```
 
@@ -33,9 +33,6 @@ config :ethereumex,
 
 ## Usage
 
-### Note
-Currently only official [DApp APIs](https://github.com/ethereum/wiki/wiki/JSON-RPC) are implemented. More features (new api methods, smart contract creation) will be added soon.
-
 ### Available methods:
 
 * web3_clientVersion
@@ -119,6 +116,19 @@ iex> Ethereumex.HttpClient.eth_get_balance(["0x407d73d8a49eeb85d32cf465507dd71d5
 ```
 Note that all method names are snakecases, so, for example, shh_getMessages method has corresponding Ethereumex.HttpClient.shh_get_messages/1 method
 
+### Custom requests
+Many Ethereum protocol implementations support additional JSON-RPC API methods. To use them, you should call Ethereumex.HttpClient.send_request/2 method.
+
+For example, let's call geth's rpc_modules method.
+
+```elixir
+iex> Ethereumex.HttpClient.send_request("rpc_modules")
+{:ok,
+ %{"id" => 5, "jsonrpc" => "2.0",
+   "result" => %{"eth" => "1.0", "net" => "1.0", "rpc" => "1.0",
+     "web3" => "1.0"}}}
+```
+
 ## Contributing
 
 1. [Fork it!](http://github.com/ayrat555/ethereumex/fork)

fixture/vcr_cassettes/http_client_custom_request.json

@@ -0,0 +1,22 @@
+[
+  {
+    "request": {
+      "body": "{\"params\":[],\"method\":\"rpc_modules\",\"jsonrpc\":\"2.0\",\"id\":3}",
+      "headers": [],
+      "method": "post",
+      "options": [],
+      "request_body": "",
+      "url": "http://localhost:8545"
+    },
+    "response": {
+      "body": "{\"jsonrpc\":\"2.0\",\"id\":3,\"result\":{\"eth\":\"1.0\",\"net\":\"1.0\",\"rpc\":\"1.0\",\"web3\":\"1.0\"}}\n",
+      "headers": {
+        "Content-Type": "application/json",
+        "Date": "Sun, 24 Sep 2017 15:55:06 GMT",
+        "Content-Length": "85"
+      },
+      "status_code": 200,
+      "type": "ok"
+    }
+  }
+]

lib/ethereumex/client.ex

@@ -1,5 +1,5 @@
 defmodule Ethereumex.Client do
-  @callback request(payload :: map) :: tuple
+  @callback request(map()) :: any()
   @moduledoc false
 
   alias Ethereumex.Client.Utils
@@ -34,16 +34,22 @@ defmodule Ethereumex.Client do
       methods
       |> Enum.each(fn({original_name, formatted_name}) ->
         def unquote(formatted_name)(params \\ []) when is_list(params) do
-          params = params |> add_method_info(unquote(original_name))
-
-          GenServer.call __MODULE__, {:request, params}
+          send_request(unquote(original_name), params)
         end
       end)
 
-      def request(_) do
+      @spec send_request(binary(), [binary()] | [map()]) :: any()
+      def send_request(method_name, params \\ []) when is_list(params) do
+        params = params |> add_method_info(method_name)
+
+        GenServer.call __MODULE__, {:request, params}
+      end
+
+      @spec request(map()) :: any()
+      def request(_payload) do
       end
 
-      @spec add_method_info([binary] | [map], binary()) :: map()
+      @spec add_method_info([binary()] | [map()], binary()) :: map()
       defp add_method_info(params, method_name) do
         %{}
         |> Map.put("method", method_name)

lib/ethereumex/http_client.ex

@@ -3,13 +3,14 @@ defmodule Ethereumex.HttpClient do
   import Ethereumex.Config
   @moduledoc false
 
-  @spec post_request(map()) :: {:ok | :error, any()}
+  @spec request(map()) :: {:ok | :error, any()}
   def request(payload) do
     payload
     |> encode_payload
     |> post_request
   end
 
+  @spec encode_payload(map()) :: binary()
   defp encode_payload(payload) do
     payload |> Poison.encode!
   end

mix.exs

@@ -3,7 +3,7 @@ defmodule Ethereumex.Mixfile do
 
   def project do
     [app: :ethereumex,
-     version: "0.1.0",
+     version: "0.1.2",
      elixir: "~> 1.4",
      description: "Elixir JSON-RPC client for the Ethereum blockchain",
      package: [

test/ethereum/http_client_test.exs

@@ -58,4 +58,23 @@ defmodule Ethereumex.HttpClientTest do
       } = result
     end
   end
+
+  test "sends custom geth request" do
+    use_cassette "http_client_custom_request" do
+      result = HttpClient.send_request("rpc_modules")
+
+      {:ok,
+       %{"id" => 3,
+	 "jsonrpc" => "2.0",
+	 "result" =>
+	   %{
+	     "eth" => "1.0",
+	     "net" => "1.0",
+	     "rpc" => "1.0",
+	     "web3" => "1.0"
+	   }
+       }
+      } = result
+    end
+  end
 end