fix to support body nil for request with content-type json

lib/req_api_logger.ex

@@ -130,9 +130,11 @@ defmodule AntlUtilsElixir.ReqApiLogger do
   defp format_request_body(%Request{} = req, hide_list) do
     case Request.get_header(req, "content-type") do
       ["application/json" <> _] ->
-        req.body
-        |> Jason.decode!()
-        |> hide(hide_list)
+        with {:ok, decoded} <- Jason.decode("#{req.body}") do
+          hide(decoded, hide_list)
+        else
+          _ -> req.body
+        end
 
       ["application/x-www-form-urlencoded"] ->
         req.body

test/req_api_logger_test.exs

@@ -178,4 +178,32 @@ defmodule AntlUtilsElixir.ReqApiLoggerTest do
       Logger.configure(level: :debug)
     end
   end
+
+  defp req_get_with_json_header(body) do
+    Req.new(url: url(), headers: [{"content-type", "application/json"}], body: body)
+    |> ReqApiLogger.attach(api_name: :test)
+    |> Req.get()
+  end
+
+  describe "ReqApiLogger regression tests : don't crash on invalid JSON request" do
+    setup do
+      TestServer.add("/")
+      :ok
+    end
+
+    test "nil body" do
+      assert capture_log(fn -> req_get_with_json_header(nil) end) =~
+               ~r/body=nil/
+    end
+
+    test "empty body" do
+      assert capture_log(fn -> req_get_with_json_header("") end) =~
+               ~r/body=""/
+    end
+
+    test "malformed json" do
+      assert capture_log(fn -> req_get_with_json_header("{") end) =~
+               ~r/body="{"/
+    end
+  end
 end