Add Erlang/OTP 27 Process label support (#446)

Author: KernelMadness

.github/workflows/ci.yml

@@ -39,6 +39,9 @@ jobs:
           - pair:
               elixir: 1.15.6
               otp: 26.0.2
+          - pair:
+              elixir: 1.17.2
+              otp: 27.0.1
             lint: lint
     steps:
       - uses: actions/checkout@v2

lib/phoenix/live_dashboard/system_info.ex

@@ -801,7 +801,12 @@ defmodule Phoenix.LiveDashboard.SystemInfo do
       case Process.info(pid, [:initial_call, :dictionary, :registered_name]) do
         [{:initial_call, initial_call}, {:dictionary, dictionary}, {:registered_name, name}] ->
           initial_call = Keyword.get(dictionary, :"$initial_call", initial_call)
-          name = if is_atom(name), do: inspect(name), else: format_initial_call(initial_call)
+
+          name =
+            format_process_label(Keyword.get(dictionary, :"$process_label")) ||
+              format_registered_name(name) ||
+              format_initial_call(initial_call)
+
           {name, initial_call}
 
         _ ->
@@ -820,6 +825,13 @@ defmodule Phoenix.LiveDashboard.SystemInfo do
     |> to_process_details()
   end
 
+  defp format_process_label(nil), do: nil
+  defp format_process_label(label) when is_binary(label), do: label
+  defp format_process_label(label), do: inspect(label)
+
+  defp format_registered_name([]), do: nil
+  defp format_registered_name(name), do: inspect(name)
+
   defp format_initial_call({:supervisor, mod, arity}), do: Exception.format_mfa(mod, :init, arity)
   defp format_initial_call({m, f, a}), do: Exception.format_mfa(m, f, a)
   defp format_initial_call(nil), do: nil

test/phoenix/live_dashboard/system_info_test.exs

@@ -38,14 +38,29 @@ defmodule Phoenix.LiveDashboard.SystemInfoTest do
     end
 
     test "all with search" do
-      process = if System.otp_release() == "26", do: :user_drv_writer, else: :user
+      process =
+        if System.otp_release() |> String.to_integer() >= 26, do: :user_drv_writer, else: :user
+
       {pids, _count, _} = SystemInfo.fetch_processes(node(), inspect(process), :memory, :asc, 100)
 
       assert [[pid, name | _]] = pids
       assert pid == {:pid, Process.whereis(process)}
       assert name == {:name_or_initial_call, inspect(process)}
     end
 
+    if System.otp_release() |> String.to_integer() >= 27 do
+      test "all with search by label" do
+        {:ok, agent_pid} = Agent.start_link(fn -> Process.set_label("test label") end)
+
+        {pids, _count, _} =
+          SystemInfo.fetch_processes(node(), "test label", :memory, :asc, 100)
+
+        assert [[pid, name | _]] = pids
+        assert pid == {:pid, agent_pid}
+        assert name == {:name_or_initial_call, "test label"}
+      end
+    end
+
     test "allows previous reductions param" do
       {_pids, _count, state} =
         SystemInfo.fetch_processes(node(), ":user", :reductions_diff, :asc, 100)
@@ -60,7 +75,7 @@ defmodule Phoenix.LiveDashboard.SystemInfoTest do
       assert is_integer(info[:message_queue_len])
 
       expected =
-        if System.otp_release() == "26",
+        if System.otp_release() |> String.to_integer() >= 26,
           do: {:group, :server, 4},
           else: {:erlang, :apply, 2}