mnesia contrib

lib/prometheus.ex

@@ -101,6 +101,7 @@ defmodule Prometheus do
       require Prometheus.Buckets
       use Prometheus.Metric
       require Prometheus.Contrib.HTTP
+      require Prometheus.Contrib.Mnesia
     end
   end
 

lib/prometheus/contrib/mnesia.ex

@@ -0,0 +1,35 @@
+defmodule Prometheus.Contrib.Mnesia do
+  @moduledoc """
+  Mnesia instrumentation helpers.
+  """
+  use Prometheus.Erlang, :prometheus_mnesia
+
+  @doc """
+  Returns sum of all mnesia files for the given `table` in bytes.
+  Mnesia can create different files for each table:
+  - .DAT - DETS files
+  - .TMP - temp files
+  - .DMP - dumped ets tables
+  - .DCD - disc copies data
+  - .DCL - disc copies log
+  - .LOGTMP - disc copies log
+
+  More on Mnesia files can be found in
+  <a href="http://erlang.org/doc/apps/mnesia/Mnesia_chap7.html">
+  Mnesia System Information chapter
+  </a> of Mnesia User's Guide
+  """
+  defmacro table_disk_size(dir \\ quote do :mnesia.system_info(:directory) end, table) do
+    Erlang.call([dir, table])
+  end
+
+  @doc """
+  Returns {pcount, ccount} tuple, where
+  pcount is a number of participant transactions and
+  ccount is a number of coordinator transactions.
+  Can return {:undefined, :undefined} occasionally.
+  """
+  defmacro tm_info() do
+    Erlang.call()
+  end
+end

mix.exs

@@ -48,7 +48,7 @@ defmodule PrometheusEx.Mixfile do
   end
 
   defp deps do
-    [{:prometheus, "~> 3.0"},
+    [{:prometheus, "~> 3.1"},
      {:excoveralls, "~> 0.5.6", only: :test},
      {:ex_doc, "~> 0.11", only: :dev},
      {:earmark, ">= 0.0.0", only: :dev}]

mix.lock

@@ -1,12 +1,12 @@
 %{"certifi": {:hex, :certifi, "0.4.0", "a7966efb868b179023618d29a407548f70c52466bf1849b9e8ebd0e34b7ea11f", [:rebar3], []},
-  "earmark": {:hex, :earmark, "1.0.1", "2c2cd903bfdc3de3f189bd9a8d4569a075b88a8981ded9a0d95672f6e2b63141", [:mix], []},
-  "ex_doc": {:hex, :ex_doc, "0.13.1", "658dbfc8cc5b0fac192f0f3254efe66ee6294200804a291549e0aeb052053bba", [:mix], [{:earmark, "~> 1.0", [hex: :earmark, optional: false]}]},
-  "excoveralls": {:hex, :excoveralls, "0.5.6", "35a903f6f78619ee7f951448dddfbef094b3a0d8581657afaf66465bc930468e", [:mix], [{:exjsx, "~> 3.0", [hex: :exjsx, optional: false]}, {:hackney, ">= 0.12.0", [hex: :hackney, optional: false]}]},
-  "exjsx": {:hex, :exjsx, "3.2.0", "7136cc739ace295fc74c378f33699e5145bead4fdc1b4799822d0287489136fb", [:mix], [{:jsx, "~> 2.6.2", [hex: :jsx, optional: false]}]},
+  "earmark": {:hex, :earmark, "1.0.2", "a0b0904d74ecc14da8bd2e6e0248e1a409a2bc91aade75fcf428125603de3853", [:mix], []},
+  "ex_doc": {:hex, :ex_doc, "0.14.3", "e61cec6cf9731d7d23d254266ab06ac1decbb7651c3d1568402ec535d387b6f7", [:mix], [{:earmark, "~> 1.0", [hex: :earmark, optional: false]}]},
+  "excoveralls": {:hex, :excoveralls, "0.5.7", "5d26e4a7cdf08294217594a1b0643636accc2ad30e984d62f1d166f70629ff50", [:mix], [{:exjsx, "~> 3.0", [hex: :exjsx, optional: false]}, {:hackney, ">= 0.12.0", [hex: :hackney, optional: false]}]},
+  "exjsx": {:hex, :exjsx, "3.2.1", "1bc5bf1e4fd249104178f0885030bcd75a4526f4d2a1e976f4b428d347614f0f", [:mix], [{:jsx, "~> 2.8.0", [hex: :jsx, optional: false]}]},
   "hackney": {:hex, :hackney, "1.6.1", "ddd22d42db2b50e6a155439c8811b8f6df61a4395de10509714ad2751c6da817", [:rebar3], [{:certifi, "0.4.0", [hex: :certifi, optional: false]}, {:idna, "1.2.0", [hex: :idna, optional: false]}, {:metrics, "1.0.1", [hex: :metrics, optional: false]}, {:mimerl, "1.0.2", [hex: :mimerl, optional: false]}, {:ssl_verify_fun, "1.1.0", [hex: :ssl_verify_fun, optional: false]}]},
   "idna": {:hex, :idna, "1.2.0", "ac62ee99da068f43c50dc69acf700e03a62a348360126260e87f2b54eced86b2", [:rebar3], []},
-  "jsx": {:hex, :jsx, "2.6.2", "213721e058da0587a4bce3cc8a00ff6684ced229c8f9223245c6ff2c88fbaa5a", [:mix, :rebar], []},
+  "jsx": {:hex, :jsx, "2.8.0", "749bec6d205c694ae1786d62cea6cc45a390437e24835fd16d12d74f07097727", [:mix, :rebar], []},
   "metrics": {:hex, :metrics, "1.0.1", "25f094dea2cda98213cecc3aeff09e940299d950904393b2a29d191c346a8486", [:rebar3], []},
   "mimerl": {:hex, :mimerl, "1.0.2", "993f9b0e084083405ed8252b99460c4f0563e41729ab42d9074fd5e52439be88", [:rebar3], []},
-  "prometheus": {:hex, :prometheus, "3.0.0", "f868b68e9532e4bed456216e06b6c0f8527dfeca103544e7faabd33282b040ea", [:rebar3], []},
+  "prometheus": {:hex, :prometheus, "3.1.0", "32a148a6c906d8d31113cad5cb07d4b61dec3f77c6f6fe2ce837d1ff62e9a049", [:rebar3], []},
   "ssl_verify_fun": {:hex, :ssl_verify_fun, "1.1.0", "edee20847c42e379bf91261db474ffbe373f8acb56e9079acb6038d4e0bf414f", [:rebar, :make], []}}

test/contrib/mnesia_test.exs

@@ -0,0 +1,36 @@
+defmodule Prometheus.Contrib.MnesiaTest do
+  use ExUnit.Case
+
+  use Prometheus
+
+  test "table disk size" do
+    {:ok, root} = :file.get_cwd()
+    mnesia_dir = root ++ '/test/mnesia'
+    set_custom_mnesia_dir(mnesia_dir)
+
+    assert mnesia_dir == :mnesia.system_info(:directory)
+
+    assert 3 = Prometheus.Contrib.Mnesia.table_disk_size(mnesia_dir, :table)
+    assert 21 = Prometheus.Contrib.Mnesia.table_disk_size(:my_table)
+  end
+
+  test "tm info test" do
+    try do
+      :mnesia.start()
+      assert {_, _} = Prometheus.Contrib.Mnesia.tm_info()
+    after
+      :mnesia.stop()
+    end
+  end
+
+  defp set_custom_mnesia_dir(dir) do
+    try do
+      :ets.lookup_element(:mnesia_gvar, :dir, 2)
+      :ets.update_element(:mnesia_gvar, :dir, dir)
+    rescue
+      ArgumentError ->
+        :application.set_env(:mnesia, :dir, dir)
+    end
+  end
+
+end

test/mnesia/my_table.DAT

@@ -0,0 +1 @@
+111111

test/mnesia/my_table.DCD

@@ -0,0 +1 @@
+11111

test/mnesia/my_table.DCL

@@ -0,0 +1 @@
+1111

test/mnesia/my_table.DMP

@@ -0,0 +1 @@
+111

test/mnesia/my_table.LOGTMP

@@ -0,0 +1 @@
+11

test/mnesia/my_table.TMP

@@ -0,0 +1 @@
+1

test/mnesia/table.DCD

@@ -0,0 +1 @@
+11

test/mnesia/table.DCL

@@ -0,0 +1 @@
+1