chore: catch the encoder exception to avoid crashing the connection process

Author: zookzook

lib/bson.ex

@@ -12,8 +12,11 @@ defmodule BSON do
   @spec encode(document) :: iodata
   def encode(map) when is_map(map) do
     case Map.has_key?(map, :__struct__) do
-      true -> BSON.Encoder.encode(Map.to_list(map))
-      false -> BSON.Encoder.encode(map)
+      true ->
+        BSON.Encoder.encode(Map.to_list(map))
+
+      false ->
+        BSON.Encoder.encode(map)
     end
   end
 
@@ -26,7 +29,8 @@ defmodule BSON do
   """
   @spec decode(iodata) :: document
   def decode(iodata) do
-    IO.iodata_to_binary(iodata)
+    iodata
+    |> IO.iodata_to_binary()
     |> BSON.Decoder.decode()
   end
 end

lib/bson/encoder.ex

@@ -64,7 +64,8 @@ defmodule BSON.Encoder do
   end
 
   def encode(value) when is_list(value) do
-    array(value, 0)
+    value
+    |> array(0)
     |> document
   end
 
@@ -95,6 +96,10 @@ defmodule BSON.Encoder do
   def encode(value) when is_int64(value),
     do: <<value::int64>>
 
+  def encode(value) do
+    raise Mongo.Error.exception("invalid document: #{inspect(value)}")
+  end
+
   def document(doc) do
     {_, iodata} =
       Enum.reduce(doc, {:unknown, ""}, fn
@@ -141,8 +146,7 @@ defmodule BSON.Encoder do
     do: [{Integer.to_string(ix), hd} | array(tl, ix + 1)]
 
   defp invalid_doc(doc) do
-    message = "invalid document containing atom and string keys: #{inspect(doc)}"
-    raise ArgumentError, message
+    raise Mongo.Error.exception("invalid document containing atom and string keys: #{inspect(doc)}")
   end
 
   defp type(%BSON.Binary{}), do: @type_binary

lib/mongo_db_connection/utils.ex

@@ -21,6 +21,10 @@ defmodule Mongo.MongoDBConnection.Utils do
          {:ok, ^id, response} <- recv_data(nil, "", state) do
       get_doc(response)
     end
+  rescue
+    error ->
+      Logger.error("Unable to send request to database because of #{inspect(error)}")
+      {:error, error, state}
   end
 
   @doc """

test/bson/encoder_test.exs

@@ -0,0 +1,7 @@
+defmodule BSON.EncoderTest do
+  use ExUnit.Case, async: true
+
+  test "return error in the case of encoder issues" do
+    assert_raise Mongo.Error, fn -> %{message: "invalid document: {:error, \"some error\"}"} = BSON.encode(%{"field" => {:error, "some error"}}) end
+  end
+end

test/bson_test.exs

@@ -204,11 +204,11 @@ defmodule BSONTest do
 
   test "mixing atoms with binaries" do
     document = 1..33 |> Enum.reduce(%{}, fn x, acc -> Map.put(acc, to_string(x), x) end) |> Map.put(:a, 10)
-    assert_raise ArgumentError, fn -> encode(document) end
+    assert_raise Mongo.Error, fn -> encode(document) end
     document = %{:key => "value", "id" => 10}
-    assert_raise ArgumentError, fn -> encode(document) end
+    assert_raise Mongo.Error, fn -> encode(document) end
     document = 1..33 |> Enum.reduce(%{}, fn x, acc -> Map.put(acc, to_string(x), x) end) |> Map.put(:__struct__, TestUser)
-    assert_raise ArgumentError, fn -> encode(document) end
+    assert_raise Mongo.Error, fn -> encode(document) end
   end
 
   defp encode(value) do

test/mongo/encoder_test.exs

@@ -37,6 +37,11 @@ defmodule Mongo.EncoderTest do
     end
   end
 
+  test "invalid document test", c do
+    coll = unique_collection()
+    assert {:error, %Mongo.Error{message: "invalid document: {:error, \"some error\"}"}} = Mongo.insert_one(c.pid, coll, %{"field" => {:error, "some error"}})
+  end
+
   test "insert encoded date with protocol", c do
     coll = unique_collection()