Return 400 for UTF-8 encoding errors

This is usually an input error from the user and should return
a 400 error.

lib/phoenix_ecto/plug.ex

@@ -57,3 +57,14 @@ unless Phoenix.Ecto.StorageNotCreatedError in excluded_exceptions do
     def storage_up(repo), do: repo.__adapter__().storage_up(repo.config())
   end
 end
+
+if Code.ensure_loaded?(Postgrex.Error) do
+  unless Postgrex.Error in excluded_exceptions do
+    defimpl Plug.Exception, for: Postgrex.Error do
+      def status(%{postgres: %{code: :character_not_in_repertoire}}), do: 400
+      def status(_), do: 500
+
+      def actions(_), do: []
+    end
+  end
+end

mix.exs

@@ -54,6 +54,7 @@ defmodule PhoenixEcto.Mixfile do
       {:phoenix_html, "~> 2.14.2 or ~> 3.0 or ~> 4.1", optional: true},
       {:ecto, "~> 3.5"},
       {:plug, "~> 1.9"},
+      {:postgrex, "~> 0.17", optional: true},
       {:ex_doc, ">= 0.0.0", only: :docs}
     ]
   end

mix.lock

@@ -1,4 +1,5 @@
 %{
+  "db_connection": {:hex, :db_connection, "2.6.0", "77d835c472b5b67fc4f29556dee74bf511bbafecdcaf98c27d27fa5918152086", [:mix], [{:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "c2f992d15725e721ec7fbc1189d4ecdb8afef76648c746a8e1cad35e3b8a35f3"},
   "decimal": {:hex, :decimal, "2.1.1", "5611dca5d4b2c3dd497dec8f68751f1f1a54755e8ed2a966c2633cf885973ad6", [:mix], [], "hexpm", "53cfe5f497ed0e7771ae1a475575603d77425099ba5faef9394932b35020ffcc"},
   "earmark_parser": {:hex, :earmark_parser, "1.4.39", "424642f8335b05bb9eb611aa1564c148a8ee35c9c8a8bba6e129d51a3e3c6769", [:mix], [], "hexpm", "06553a88d1f1846da9ef066b87b57c6f605552cfbe40d20bd8d59cc6bde41944"},
   "ecto": {:hex, :ecto, "3.10.3", "eb2ae2eecd210b4eb8bece1217b297ad4ff824b4384c0e3fdd28aaf96edd6135", [:mix], [{:decimal, "~> 1.6 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "44bec74e2364d491d70f7e42cd0d690922659d329f6465e89feb8a34e8cd3433"},
@@ -11,5 +12,6 @@
   "phoenix_html": {:hex, :phoenix_html, "3.3.1", "4788757e804a30baac6b3fc9695bf5562465dd3f1da8eb8460ad5b404d9a2178", [:mix], [{:plug, "~> 1.5", [hex: :plug, repo: "hexpm", optional: true]}], "hexpm", "bed1906edd4906a15fd7b412b85b05e521e1f67c9a85418c55999277e553d0d3"},
   "plug": {:hex, :plug, "1.14.2", "cff7d4ec45b4ae176a227acd94a7ab536d9b37b942c8e8fa6dfc0fff98ff4d80", [:mix], [{:mime, "~> 1.0 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:plug_crypto, "~> 1.1.1 or ~> 1.2", [hex: :plug_crypto, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4.3 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "842fc50187e13cf4ac3b253d47d9474ed6c296a8732752835ce4a86acdf68d13"},
   "plug_crypto": {:hex, :plug_crypto, "1.2.5", "918772575e48e81e455818229bf719d4ab4181fcbf7f85b68a35620f78d89ced", [:mix], [], "hexpm", "26549a1d6345e2172eb1c233866756ae44a9609bd33ee6f99147ab3fd87fd842"},
+  "postgrex": {:hex, :postgrex, "0.17.5", "0483d054938a8dc069b21bdd636bf56c487404c241ce6c319c1f43588246b281", [:mix], [{:db_connection, "~> 2.1", [hex: :db_connection, repo: "hexpm", optional: false]}, {:decimal, "~> 1.5 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:table, "~> 0.1.0", [hex: :table, repo: "hexpm", optional: true]}], "hexpm", "50b8b11afbb2c4095a3ba675b4f055c416d0f3d7de6633a595fc131a828a67eb"},
   "telemetry": {:hex, :telemetry, "1.2.1", "68fdfe8d8f05a8428483a97d7aab2f268aaff24b49e0f599faa091f1d4e7f61c", [:rebar3], [], "hexpm", "dad9ce9d8effc621708f99eac538ef1cbe05d6a874dd741de2e689c47feafed5"},
 }