Drive-by flaky test fix

test/statix/config_test.exs

@@ -1,10 +1,11 @@
 defmodule Statix.ConfigTest do
-  use Statix.TestCase, async: false
+  use Statix.TestCase, async: false, auto_connect: false
 
   use Statix, runtime_config: true
 
   test "connect/1" do
-    connect(tags: ["tag:test"], prefix: "foo")
+    port = Statix.TestServer.get_port(__MODULE__.Server)
+    connect(port: port, tags: ["tag:test"], prefix: "foo")
 
     increment("sample", 2)
     assert_receive {:test_server, _, "foo.sample:2|c|#tag:test"}
@@ -13,7 +14,8 @@ defmodule Statix.ConfigTest do
   test "global tags when present" do
     Application.put_env(:statix, :tags, ["tag:test"])
 
-    connect()
+    port = Statix.TestServer.get_port(__MODULE__.Server)
+    connect(port: port)
 
     increment("sample", 3)
     assert_receive {:test_server, _, "sample:3|c|#tag:test"}
@@ -27,7 +29,8 @@ defmodule Statix.ConfigTest do
   test "global connection-specific tags" do
     Application.put_env(:statix, __MODULE__, tags: ["tag:test"])
 
-    connect()
+    port = Statix.TestServer.get_port(__MODULE__.Server)
+    connect(port: port)
 
     set("sample", 4)
     assert_receive {:test_server, _, "sample:4|s|#tag:test"}

test/statix/overriding_test.exs

@@ -35,9 +35,6 @@ defmodule Statix.OverridingTest do
     super([key, "-overridden"], value, options)
   end
 
-  setup do
-    connect()
-  end
 
   test "increment/3" do
     increment("sample", 3, tags: ["foo"])

test/statix/pool_test.exs

@@ -6,7 +6,8 @@ defmodule Statix.PoolingTest do
   @pool_size 3
 
   setup do
-    connect(pool_size: @pool_size)
+    port = Statix.TestServer.get_port(__MODULE__.Server)
+    connect(port: port, pool_size: @pool_size)
   end
 
   test "starts :pool_size number of ports and randomly picks one" do

test/statix_test.exs

@@ -16,9 +16,6 @@ defmodule StatixTest do
     end)
   end
 
-  setup do
-    connect()
-  end
 
   test "increment/1,2,3" do
     __MODULE__.increment("sample")
@@ -160,22 +157,22 @@ defmodule StatixTest do
 
     assert capture_log(fn ->
              assert {:error, :port_closed} == increment("sample")
-           end) =~ "counter metric \"sample\" lost value 1 error=:port_closed\n\e[0m"
+           end) =~ "counter metric \"sample\" lost value 1 error=:port_closed"
 
     assert capture_log(fn ->
              assert {:error, :port_closed} == decrement("sample")
-           end) =~ "counter metric \"sample\" lost value -1 error=:port_closed\n\e[0m"
+           end) =~ "counter metric \"sample\" lost value -1 error=:port_closed"
 
     assert capture_log(fn ->
              assert {:error, :port_closed} == gauge("sample", 2)
-           end) =~ "gauge metric \"sample\" lost value 2 error=:port_closed\n\e[0m"
+           end) =~ "gauge metric \"sample\" lost value 2 error=:port_closed"
 
     assert capture_log(fn ->
              assert {:error, :port_closed} == histogram("sample", 3)
-           end) =~ "histogram metric \"sample\" lost value 3 error=:port_closed\n\e[0m"
+           end) =~ "histogram metric \"sample\" lost value 3 error=:port_closed"
 
     assert capture_log(fn ->
              assert {:error, :port_closed} == timing("sample", 2.5)
-           end) =~ "timing metric \"sample\" lost value 2.5 error=:port_closed\n\e[0m"
+           end) =~ "timing metric \"sample\" lost value 2.5 error=:port_closed"
   end
 end

test/support/test_server.exs

@@ -2,16 +2,26 @@ defmodule Statix.TestServer do
   use GenServer
 
   def start_link(port, test_module) do
-    GenServer.start_link(__MODULE__, port, name: test_module)
+    GenServer.start_link(__MODULE__, {port, test_module}, name: test_module)
+  end
+
+  def get_port(test_module) do
+    GenServer.call(test_module, :get_port)
   end
 
   @impl true
-  def init(port) do
+  def init({port, _test_module}) do
     {:ok, socket} = :gen_udp.open(port, [:binary, active: true])
     Process.flag(:trap_exit, true)
     {:ok, %{socket: socket, test: nil}}
   end
 
+  @impl true
+  def handle_call(:get_port, _from, %{socket: socket} = state) do
+    {:ok, port} = :inet.port(socket)
+    {:reply, port, state}
+  end
+
   @impl true
   def handle_call({:set_current_test, current_test}, _from, %{test: test} = state) do
     if is_nil(test) or is_nil(current_test) do

test/test_helper.exs

@@ -6,7 +6,9 @@ defmodule Statix.TestCase do
   use ExUnit.CaseTemplate
 
   using options do
-    port = Keyword.get(options, :port, 8125)
+    # Use random high port to avoid collisions with typical infra (statsd/dogstatsd)
+    port = Keyword.get(options, :port, 8125 + :rand.uniform(10000))
+    auto_connect = Keyword.get(options, :auto_connect, true)
 
     quote do
       setup_all do
@@ -16,6 +18,13 @@ defmodule Statix.TestCase do
 
       setup do
         Statix.TestServer.setup(__MODULE__.Server)
+
+        if unquote(auto_connect) do
+          port = Statix.TestServer.get_port(__MODULE__.Server)
+          connect(port: port)
+        end
+
+        :ok
       end
     end
   end