Supports passing exchange pair's rate as string (#1000)

* Fix exchange pair not accepting rate as string

* Update OpenAPI specs

apps/admin_api/lib/admin_api/v1/controllers/exchange_pair_controller.ex

@@ -77,6 +77,9 @@ defmodule AdminAPI.V1.ExchangePairController do
 
       {:error, code} ->
         handle_error(conn, code)
+
+      {:error, code, description} ->
+        handle_error(conn, code, description)
     end
   end
 
@@ -98,6 +101,9 @@ defmodule AdminAPI.V1.ExchangePairController do
 
       {:error, code} ->
         handle_error(conn, code)
+
+      {:error, code, description} ->
+        handle_error(conn, code, description)
     end
   end
 

apps/admin_api/priv/spec.json

@@ -5621,7 +5621,14 @@
                     "type": "string"
                   },
                   "rate": {
-                    "type": "number"
+                    "oneOf": [
+                      {
+                        "type": "string"
+                      },
+                      {
+                        "type": "number"
+                      }
+                    ]
                   },
                   "sync_opposite": {
                     "type": "boolean"
@@ -6088,7 +6095,14 @@
                     "type": "string"
                   },
                   "rate": {
-                    "type": "number"
+                    "oneOf": [
+                      {
+                        "type": "string"
+                      },
+                      {
+                        "type": "number"
+                      }
+                    ]
                   }
                 },
                 "required": [

apps/admin_api/priv/spec.yaml

@@ -1438,7 +1438,9 @@ paths:
                 to_token_id:
                   type: string
                 rate:
-                  type: number
+                  oneOf:
+                    - type: string
+                    - type: number
                 sync_opposite:
                   type: boolean
               required:
@@ -1472,7 +1474,9 @@ paths:
                 id:
                   type: string
                 rate:
-                  type: number
+                  oneOf:
+                    - type: string
+                    - type: number
               required:
                 - id
               example:

apps/admin_api/priv/swagger/exchange_pair/request_bodies.yaml

@@ -23,7 +23,9 @@ ExchangePairCreateBody:
             to_token_id:
               type: string
             rate:
-              type: number
+              oneOf:
+                - type: string
+                - type: number
             sync_opposite:
               type: boolean
           required:
@@ -45,7 +47,9 @@ ExchangePairUpdateBody:
             id:
               type: string
             rate:
-              type: number
+              oneOf:
+                - type: string
+                - type: number
           required:
             - id
           example:

apps/admin_api/test/admin_api/v1/controllers/exchange_pair_controller_test.exs

@@ -200,6 +200,21 @@ defmodule AdminAPI.V1.ExchangePairControllerTest do
       assert opposite["opposite_exchange_pair"]["id"] == pair["id"]
     end
 
+    test_with_auths "accepts the rate attribute as string" do
+      request_data = %{sync_opposite: true} |> insert_params() |> Map.put(:rate, "3.14159")
+      response = request("/exchange_pair.create", request_data)
+
+      assert response["success"] == true
+      assert response["data"]["object"] == "list"
+
+      pair = Enum.at(response["data"]["data"], 0)
+
+      assert pair["object"] == "exchange_pair"
+      assert pair["from_token_id"] == request_data.from_token_id
+      assert pair["to_token_id"] == request_data.to_token_id
+      assert pair["rate"] == 3.14159
+    end
+
     test_with_auths "returns client:invalid_parameter error if given an exchange rate of 0" do
       request_data = insert_params(%{rate: 0})
       response = request("/exchange_pair.create", request_data)
@@ -236,6 +251,18 @@ defmodule AdminAPI.V1.ExchangePairControllerTest do
                "Invalid parameter provided. `rate` can't be blank."
     end
 
+    test_with_auths "returns client:invalid_parameter error if rate is not parsable" do
+      request_data = insert_params(%{rate: "1.2345rate"})
+      response = request("/exchange_pair.create", request_data)
+
+      assert response["success"] == false
+      assert response["data"]["object"] == "error"
+      assert response["data"]["code"] == "client:invalid_parameter"
+
+      assert response["data"]["description"] ==
+               "Invalid parameter provided. `rate` cannot be parsed. Got: \"1.2345rate\""
+    end
+
     test_with_auths "returns client:invalid_parameter error if from_token_id is not provided" do
       request_data = insert_params(%{from_token_id: nil})
       response = request("/exchange_pair.create", request_data)
@@ -397,6 +424,23 @@ defmodule AdminAPI.V1.ExchangePairControllerTest do
       assert opposite["opposite_exchange_pair"]["id"] == pair["id"]
     end
 
+    test_with_auths "accepts the rate attribute as string" do
+      exchange_pair = :exchange_pair |> insert() |> Repo.preload([:from_token, :to_token])
+
+      assert exchange_pair.rate != "999.99"
+
+      # Prepare the update data while keeping only id the same
+      request_data = %{
+        id: exchange_pair.id,
+        rate: "999.99"
+      }
+
+      response = request("/exchange_pair.update", request_data)
+
+      assert response["success"] == true
+      hd(response["data"]["data"])["rate"] == 999.99
+    end
+
     test_with_auths "reverts and returns error if sync_opposite: true but opposite pair is not found" do
       exchange_pair =
         :exchange_pair
@@ -463,6 +507,18 @@ defmodule AdminAPI.V1.ExchangePairControllerTest do
                "Invalid parameter provided. `rate` must be greater than 0."
     end
 
+    test_with_auths "returns client:invalid_parameter error if rate is not parsable" do
+      pair = :exchange_pair |> insert() |> Repo.preload([:from_token, :to_token])
+      response = request("/exchange_pair.update", %{id: pair.id, rate: "3.14159pi"})
+
+      assert response["success"] == false
+      assert response["data"]["object"] == "error"
+      assert response["data"]["code"] == "client:invalid_parameter"
+
+      assert response["data"]["description"] ==
+               "Invalid parameter provided. `rate` cannot be parsed. Got: \"3.14159pi\""
+    end
+
     defp assert_update_logs(logs, originator, target) do
       assert Enum.count(logs) == 1
 

apps/ewallet/lib/ewallet/gates/exchange_pair_gate.ex

@@ -23,7 +23,17 @@ defmodule EWallet.ExchangePairGate do
   @doc """
   Inserts an exchange pair.
   """
-  @spec insert(map()) :: {:ok, [%ExchangePair{}]} | {:error, atom() | Ecto.Changeset.t()}
+  @spec insert(map()) ::
+          {:ok, [%ExchangePair{}]}
+          | {:error, atom() | Ecto.Changeset.t()}
+          | {:error, atom(), String.t()}
+  def insert(%{"rate" => rate} = attrs) when is_binary(rate) do
+    case cast_rate(attrs) do
+      {:ok, casted} -> insert(casted)
+      error -> error
+    end
+  end
+
   def insert(attrs) do
     Repo.transaction(fn ->
       with {:ok, direct} <- insert(:direct, attrs),
@@ -68,7 +78,16 @@ defmodule EWallet.ExchangePairGate do
   Updates an exchange pair.
   """
   @spec update(String.t(), map()) ::
-          {:ok, [%ExchangePair{}]} | {:error, atom() | Ecto.Changeset.t()}
+          {:ok, [%ExchangePair{}]}
+          | {:error, atom() | Ecto.Changeset.t()}
+          | {:error, atom(), String.t()}
+  def update(id, %{"rate" => rate} = attrs) when is_binary(rate) do
+    case cast_rate(attrs) do
+      {:ok, casted} -> update(id, casted)
+      error -> error
+    end
+  end
+
   def update(id, attrs) do
     Repo.transaction(fn ->
       with {:ok, direct} <- update(:direct, id, attrs),
@@ -119,6 +138,18 @@ defmodule EWallet.ExchangePairGate do
 
   defp update(:opposite, _, _), do: {:ok, nil}
 
+  defp cast_rate(%{"rate" => rate} = attrs) do
+    case Float.parse(rate) do
+      # Only a succesful parsing without any binary remainder shall proceed
+      {parsed, ""} ->
+        {:ok, Map.put(attrs, "rate", parsed)}
+
+      _ ->
+        {:error, :invalid_parameter,
+         "Invalid parameter provided. `rate` cannot be parsed. Got: #{inspect(rate)}"}
+    end
+  end
+
   @doc """
   Deletes an exchange pair.
   """

apps/ewallet/test/ewallet/gates/exchange_pair_gate_test.exs

@@ -69,6 +69,43 @@ defmodule EWallet.ExchangePairGateTest do
       assert Enum.at(pairs, 1).rate == 1 / 2.0
     end
 
+    test "accepts the rate as string" do
+      eth = insert(:token)
+      omg = insert(:token)
+
+      {res, pairs} =
+        ExchangePairGate.insert(%{
+          "rate" => "3.14159",
+          "from_token_id" => eth.id,
+          "to_token_id" => omg.id,
+          "sync_opposite" => true,
+          "originator" => %System{}
+        })
+
+      assert res == :ok
+      assert hd(pairs).rate == 3.14159
+    end
+
+    test "returns error if the string rate cannot be parsed" do
+      eth = insert(:token)
+      omg = insert(:token)
+
+      {res, error, description} =
+        ExchangePairGate.insert(%{
+          "rate" => "not a rate",
+          "from_token_id" => eth.id,
+          "to_token_id" => omg.id,
+          "sync_opposite" => true,
+          "originator" => %System{}
+        })
+
+      assert res == :error
+      assert error == :invalid_parameter
+
+      assert description ==
+               "Invalid parameter provided. `rate` cannot be parsed. Got: \"not a rate\""
+    end
+
     test "rollbacks if an error occurred along the way" do
       eth = insert(:token)
       omg = insert(:token)