Add User.create_session/1 to generate a new access_token

Author: nitinstp23

config/config.exs

@@ -4,4 +4,8 @@ use Mix.Config
 
 config :kite_connect_ex,
   api_key: "api-key",
-  api_secret: "api-secret"
+  api_secret: "api-secret",
+  request_options: [
+    timeout: 5_000,
+    recv_timeout: 5_000
+  ]

lib/kite_connect_ex/response.ex

@@ -6,19 +6,35 @@ defmodule KiteConnectEx.Response do
   @success_status_codes [200, 201]
   @server_error_status_code 500
 
+  @success_status "success"
+
+  @doc false
   @spec parse_response(HTTPoison.Response.t()) :: success | error
   def parse_response(%HTTPoison.Response{} = response) do
     case response do
       %{body: body, status_code: status} when status in @success_status_codes ->
-        {:ok, Jason.decode!(body)}
+        parse_body(body)
 
       %{body: body, status_code: status} ->
         {:error, Jason.decode!(body), status}
     end
   end
 
+  @doc false
   @spec parse_error(HTTPoison.Error.t()) :: error
   def parse_error(%HTTPoison.Error{} = error) do
     {:error, "invalid response - " <> inspect(error), @server_error_status_code}
   end
+
+  defp parse_body(%{"status" => @success_status, "data" => data} = body) do
+    Jason.decode(data)
+    |> case do
+      {:ok, data} -> {:ok, data}
+      {:error, _error} -> {:error, body, @server_error_status_code}
+    end
+  end
+
+  defp parse_body(body) do
+    {:error, body, @server_error_status_code}
+  end
 end

lib/kite_connect_ex/user.ex

@@ -8,6 +8,49 @@ defmodule KiteConnectEx.User do
   alias KiteConnectEx.Request
 
   @login_url "https://kite.zerodha.com/connect/login"
+  @create_session_path "/session/token"
+
+  @keys [
+    access_token: nil,
+    api_key: nil,
+    avatar_url: nil,
+    broker: nil,
+    email: nil,
+    exchanges: nil,
+    login_time: nil,
+    meta: nil,
+    order_types: nil,
+    products: nil,
+    public_token: nil,
+    refresh_token: nil,
+    silo: nil,
+    user_id: nil,
+    user_name: nil,
+    user_shortname: nil,
+    user_type: nil
+  ]
+
+  @type t :: %__MODULE__{
+          access_token: String.t(),
+          api_key: String.t(),
+          avatar_url: String.t(),
+          broker: String.t(),
+          email: String.t(),
+          exchanges: List.t(),
+          login_time: String.t(),
+          meta: map(),
+          order_types: List.t(),
+          products: List.t(),
+          public_token: String.t(),
+          refresh_token: String.t(),
+          silo: String.t(),
+          user_id: String.t(),
+          user_name: String.t(),
+          user_shortname: String.t(),
+          user_type: String.t()
+        }
+
+  defstruct [:original_json | @keys]
 
   @doc """
   Get KiteConnect login endpoint
@@ -27,4 +70,70 @@ defmodule KiteConnectEx.User do
   defp api_key do
     Application.get_env(:kite_connect_ex, :api_key)
   end
+
+  @doc """
+  Generate `access_token` using the `request_token`
+
+  ## Example
+
+    {:ok, user_profile} = KiteConnectEx.User.create_session("request-token")
+  """
+  @spec create_session(String.t()) :: {:ok, %__MODULE__{}} | Response.error()
+  def create_session(request_token) when is_binary(request_token) do
+    params = %{
+      api_key: api_key(),
+      request_token: request_token,
+      checksum: generate_checksum(request_token)
+    }
+
+    Request.post(@create_session_path, params, [], request_options())
+    |> case do
+      {:ok, user_data} ->
+        user = %__MODULE__{new(user_data) | original_json: user_data}
+
+        {:ok, user}
+
+      {:error, error, status} ->
+        {:error, error, status}
+    end
+  end
+
+  defp generate_checksum(request_token) do
+    :crypto.hash(:sha256, api_key() <> request_token <> api_secret())
+    |> Base.encode16(case: :lower)
+  end
+
+  defp api_secret do
+    Application.get_env(:kite_connect_ex, :api_secret)
+  end
+
+  defp request_options do
+    Application.get_env(:kite_connect_ex, :request_options, [])
+  end
+
+  defp new(attributes) when is_map(attributes) do
+    struct(__MODULE__, %{
+      access_token: attributes["access_token"],
+      api_key: attributes["api_key"],
+      avatar_url: attributes["avatar_url"],
+      broker: attributes["broker"],
+      email: attributes["email"],
+      exchanges: attributes["exchanges"],
+      login_time: attributes["login_time"],
+      meta: attributes["meta"],
+      order_types: attributes["order_types"],
+      products: attributes["products"],
+      public_token: attributes["public_token"],
+      refresh_token: attributes["refresh_token"],
+      silo: attributes["silo"],
+      user_id: attributes["user_id"],
+      user_name: attributes["user_name"],
+      user_shortname: attributes["user_shortname"],
+      user_type: attributes["user_type"]
+    })
+  end
+
+  defp new(_) do
+    struct(__MODULE__, %{})
+  end
 end

mix.exs

@@ -26,7 +26,7 @@ defmodule KiteconnectEx.MixProject do
   defp deps do
     [
       {:httpoison, "~> 1.7"},
-      {:jason, "~> 1.2"}
+      {:jason, "~> 1.1"}
     ]
   end