Do not error on empty string custom prop value

lib/plausible_web/controllers/api/external_controller.ex

@@ -200,23 +200,21 @@ defmodule PlausibleWeb.Api.ExternalController do
   defp parse_meta(params) do
     raw_meta = params["m"] || params["meta"] || params["p"] || params["props"]
 
-    with {:ok, parsed_json} <- decode_raw_props(raw_meta),
-         :ok <- validate_custom_props(parsed_json) do
-      parsed_json
-    else
-      _ -> %{}
+    case decode_raw_props(raw_meta) do
+      {:ok, parsed_json} ->
+        Enum.filter(parsed_json, fn
+          {_, ""} -> false
+          {_, val} when is_list(val) -> false
+          {_, val} when is_map(val) -> false
+          _ -> true
+        end)
+        |> Map.new()
+
+      _ ->
+        %{}
     end
   end
 
-  defp validate_custom_props(props) do
-    is_valid =
-      Enum.all?(props, fn {_key, val} ->
-        !is_list(val) && !is_map(val)
-      end)
-
-    if is_valid, do: :ok, else: :invalid_props
-  end
-
   defp decode_raw_props(props) when is_map(props), do: {:ok, props}
 
   defp decode_raw_props(raw_json) when is_binary(raw_json) do

test/plausible_web/controllers/api/external_controller_test.exs

@@ -509,7 +509,7 @@ defmodule PlausibleWeb.Api.ExternalControllerTest do
         name: "Signup",
         url: "http://gigride.live/",
         domain: "custom-prop-test-4.com",
-        props: Jason.encode!(%{wat: ["some-thing"]})
+        props: Jason.encode!(%{wat: ["some-thing"], other: "key"})
       }
 
       conn = post(conn, "/api/event", params)
@@ -518,8 +518,8 @@ defmodule PlausibleWeb.Api.ExternalControllerTest do
 
       event = get_event("custom-prop-test-4.com")
 
-      assert Map.get(event, :"meta.key") == []
-      assert Map.get(event, :"meta.value") == []
+      assert Map.get(event, :"meta.key") == ["other"]
+      assert Map.get(event, :"meta.value") == ["key"]
     end
 
     test "ignores custom prop with map value", %{conn: conn} do
@@ -527,7 +527,7 @@ defmodule PlausibleWeb.Api.ExternalControllerTest do
         name: "Signup",
         url: "http://gigride.live/",
         domain: "custom-prop-test-5.com",
-        props: Jason.encode!(%{foo: %{bar: "baz"}})
+        props: Jason.encode!(%{foo: %{bar: "baz"}, other_key: 1})
       }
 
       conn = post(conn, "/api/event", params)
@@ -536,8 +536,26 @@ defmodule PlausibleWeb.Api.ExternalControllerTest do
 
       event = get_event("custom-prop-test-5.com")
 
-      assert Map.get(event, :"meta.key") == []
-      assert Map.get(event, :"meta.value") == []
+      assert Map.get(event, :"meta.key") == ["other_key"]
+      assert Map.get(event, :"meta.value") == ["1"]
+    end
+
+    test "ignores custom prop with empty string value", %{conn: conn} do
+      params = %{
+        name: "Signup",
+        url: "http://gigride.live/",
+        domain: "custom-prop-test-empty-string-val.com",
+        props: Jason.encode!(%{foo: "", other_key: true})
+      }
+
+      conn = post(conn, "/api/event", params)
+
+      assert conn.status == 202
+
+      event = get_event("custom-prop-test-empty-string-val.com")
+
+      assert Map.get(event, :"meta.key") == ["other_key"]
+      assert Map.get(event, :"meta.value") == ["true"]
     end
 
     test "ignores a malformed referrer URL", %{conn: conn} do