Param and session filtering (#27)

* Use Span.to_map to test Plug.set_conn_data/2

The current Elixir integration version automatically handles the skip
parameter and skip session data options, meaning that logic can be
removed from the Plug integration. To make sure everything keeps
working, this patch adds two tests that ensure the params and session
data is properly set right now, and after the removal.

* Remove config checks for params and session data

Since appsignal 2.2.13 (which includes
appsignal/appsignal-elixir#771 and
appsignal/appsignal-elixir#772), the app's
configuration is checked whenever parameters or session data is added to
the current span.

This patch updates the appsignal version dependency to 2.2.13 or higher,
and removes the duplicate checks from Appsignal.Plug.

Author: jeffkreeftmeijer

.changesets/remove-duplicate-session-and-param-filter-checks.md

@@ -0,0 +1,6 @@
+---
+bump: "patch"
+type: "remove"
+---
+
+Remove duplicate session and param filter checks

lib/appsignal_plug.ex

@@ -166,33 +166,21 @@ defmodule Appsignal.Plug do
   end
 
   defp set_params(span, conn) do
-    set_params(span, Application.get_env(:appsignal, :config), conn)
-  end
-
-  defp set_params(span, %{send_params: true}, conn) do
     %Plug.Conn{params: params} = Plug.Conn.fetch_query_params(conn)
     @span.set_sample_data(span, "params", params)
   end
 
-  defp set_params(span, _config, _conn) do
-    span
-  end
-
   defp set_sample_data(span, conn) do
     @span.set_sample_data(span, "environment", Appsignal.Metadata.metadata(conn))
   end
 
-  defp set_session_data(span, conn) do
-    set_session_data(span, Application.get_env(:appsignal, :config), conn)
-  end
-
-  defp set_session_data(span, %{send_session_data: true}, %Plug.Conn{
+  defp set_session_data(span, %Plug.Conn{
          private: %{plug_session: session, plug_session_fetch: :done}
        }) do
     @span.set_sample_data(span, "session_data", session)
   end
 
-  defp set_session_data(span, _config, _conn) do
+  defp set_session_data(span, _conn) do
     span
   end
 end

mix.exs

@@ -45,7 +45,7 @@ defmodule Appsignal.Plug.MixProject do
 
     [
       {:plug, ">= 1.1.0"},
-      {:appsignal, ">= 2.2.10 and < 3.0.0"},
+      {:appsignal, ">= 2.2.13 and < 3.0.0"},
       {:credo, "~> 1.2", only: [:dev, :test], runtime: false},
       {:dialyxir, "~> 1.0", only: [:dev, :test], runtime: false},
       {:ex_doc, "~> 0.21", only: :dev, runtime: false}

test/appsignal_plug_test.exs

@@ -459,7 +459,7 @@ defmodule Appsignal.PlugTest do
       assert Appsignal.Plug.set_conn_data(span, %Plug.Conn{method: "GET", params: %{"id" => "4"}}) ==
                span
 
-      assert sample_data("params", %{"id" => "4"})
+      assert %{"sample_data" => %{"params" => ~s({"id":"4"})}} = Appsignal.Span.to_map(span)
     end
 
     test "does not set params when send_params is set to false", %{span: span} do
@@ -472,7 +472,8 @@ defmodule Appsignal.PlugTest do
         Application.put_env(:appsignal, :config, config)
       end
 
-      refute sample_data("params", %{"id" => "4"})
+      %{"sample_data" => sample_data} = Appsignal.Span.to_map(span)
+      refute Map.has_key?(sample_data, "params")
     end
 
     test "sets the span's session data", %{span: span} do
@@ -485,12 +486,15 @@ defmodule Appsignal.PlugTest do
                }
              }) == span
 
-      assert sample_data("session_data", %{key: "value"})
+      %{"sample_data" => sample_data} = Appsignal.Span.to_map(span)
+      assert ~s({"key":"value"}) == sample_data["session_data"]
     end
 
     test "does not set unfetched session data", %{span: span} do
       assert Appsignal.Plug.set_conn_data(span, %Plug.Conn{}) == span
-      refute sample_data("session_data", %{key: "value"})
+
+      %{"sample_data" => sample_data} = Appsignal.Span.to_map(span)
+      refute Map.has_key?(sample_data, "session_data")
     end
 
     test "does not set session data when send_session_data is set to false", %{span: span} do
@@ -510,7 +514,8 @@ defmodule Appsignal.PlugTest do
         Application.put_env(:appsignal, :config, config)
       end
 
-      refute sample_data("session_data", %{key: "value"})
+      %{"sample_data" => sample_data} = Appsignal.Span.to_map(span)
+      refute Map.has_key?(sample_data, "session_data")
     end
   end