Add Prometheus metrics support to APRS application

- Add telemetry_metrics_prometheus dependency
- Configure Prometheus exporter in telemetry module
- Add metrics endpoint to application endpoint
- Expose /metrics for Prometheus scraping

This enables the application to be monitored by the Prometheus stack.

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

lib/aprsme_web/endpoint.ex

@@ -52,5 +52,12 @@ defmodule AprsmeWeb.Endpoint do
   plug Plug.MethodOverride
   plug Plug.Head
   plug Plug.Session, @session_options
+
+  # Health check endpoint
+  plug AprsmeWeb.Plugs.HealthCheck
+
+  # Prometheus metrics endpoint
+  plug TelemetryMetricsPrometheus
+
   plug AprsmeWeb.Router
 end

lib/aprsme_web/telemetry.ex

@@ -13,9 +13,10 @@ defmodule AprsmeWeb.Telemetry do
     children = [
       # Telemetry poller will execute the given period measurements
       # every 10_000ms. Learn more here: https://hexdocs.pm/telemetry_metrics
-      {:telemetry_poller, measurements: periodic_measurements(), period: 10_000}
+      {:telemetry_poller, measurements: periodic_measurements(), period: 10_000},
       # Add reporters as children of your supervision tree.
       # {Telemetry.Metrics.ConsoleReporter, metrics: metrics()}
+      {TelemetryMetricsPrometheus, [metrics: metrics()]}
     ]
 
     Supervisor.init(children, strategy: :one_for_one)

mix.exs

@@ -83,6 +83,7 @@ defmodule Aprsme.MixProject do
       {:resend, "~> 0.4.1"},
       {:telemetry_metrics, "~> 1.0"},
       {:telemetry_poller, "~> 1.0"},
+      {:telemetry_metrics_prometheus, "~> 1.1"},
       aprs_dep(),
       {:esbuild, "~> 0.9", runtime: Mix.env() == :dev},
       {:tailwind, "~> 0.3", runtime: Mix.env() == :dev},

mix.lock

@@ -6,6 +6,9 @@
   "cachex": {:hex, :cachex, "4.1.1", "574c5cd28473db313a0a76aac8c945fe44191659538ca6a1e8946ec300b1a19f", [:mix], [{:eternal, "~> 1.2", [hex: :eternal, repo: "hexpm", optional: false]}, {:ex_hash_ring, "~> 6.0", [hex: :ex_hash_ring, repo: "hexpm", optional: false]}, {:jumper, "~> 1.0", [hex: :jumper, repo: "hexpm", optional: false]}, {:sleeplocks, "~> 1.1", [hex: :sleeplocks, repo: "hexpm", optional: false]}, {:unsafe, "~> 1.0", [hex: :unsafe, repo: "hexpm", optional: false]}], "hexpm", "d6b7449ff98d6bb92dda58bd4fc3189cae9f99e7042054d669596f56dc503cd8"},
   "certifi": {:hex, :certifi, "2.15.0", "0e6e882fcdaaa0a5a9f2b3db55b1394dba07e8d6d9bcad08318fb604c6839712", [:rebar3], [], "hexpm", "b147ed22ce71d72eafdad94f055165c1c182f61a2ff49df28bcc71d1d5b94a60"},
   "comeonin": {:hex, :comeonin, "5.5.1", "5113e5f3800799787de08a6e0db307133850e635d34e9fab23c70b6501669510", [:mix], [], "hexpm", "65aac8f19938145377cee73973f192c5645873dcf550a8a6b18187d17c13ccdb"},
+  "cowboy": {:hex, :cowboy, "2.13.0", "09d770dd5f6a22cc60c071f432cd7cb87776164527f205c5a6b0f24ff6b38990", [:make, :rebar3], [{:cowlib, ">= 2.14.0 and < 3.0.0", [hex: :cowlib, repo: "hexpm", optional: false]}, {:ranch, ">= 1.8.0 and < 3.0.0", [hex: :ranch, repo: "hexpm", optional: false]}], "hexpm", "e724d3a70995025d654c1992c7b11dbfea95205c047d86ff9bf1cda92ddc5614"},
+  "cowboy_telemetry": {:hex, :cowboy_telemetry, "0.4.0", "f239f68b588efa7707abce16a84d0d2acf3a0f50571f8bb7f56a15865aae820c", [:rebar3], [{:cowboy, "~> 2.7", [hex: :cowboy, repo: "hexpm", optional: false]}, {:telemetry, "~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "7d98bac1ee4565d31b62d59f8823dfd8356a169e7fcbb83831b8a5397404c9de"},
+  "cowlib": {:hex, :cowlib, "2.15.0", "3c97a318a933962d1c12b96ab7c1d728267d2c523c25a5b57b0f93392b6e9e25", [:make, :rebar3], [], "hexpm", "4f00c879a64b4fe7c8fcb42a4281925e9ffdb928820b03c3ad325a617e857532"},
   "credo": {:hex, :credo, "1.7.12", "9e3c20463de4b5f3f23721527fcaf16722ec815e70ff6c60b86412c695d426c1", [:mix], [{:bunt, "~> 0.2.1 or ~> 1.0", [hex: :bunt, repo: "hexpm", optional: false]}, {:file_system, "~> 0.2 or ~> 1.0", [hex: :file_system, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "8493d45c656c5427d9c729235b99d498bd133421f3e0a683e5c1b561471291e5"},
   "db_connection": {:hex, :db_connection, "2.8.0", "64fd82cfa6d8e25ec6660cea73e92a4cbc6a18b31343910427b702838c4b33b2", [:mix], [{:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "008399dae5eee1bf5caa6e86d204dcb44242c82b1ed5e22c881f2c34da201b15"},
   "decimal": {:hex, :decimal, "2.3.0", "3ad6255aa77b4a3c4f818171b12d237500e63525c2fd056699967a3e7ea20f62", [:mix], [], "hexpm", "a4d66355cb29cb47c3cf30e71329e58361cfcb37c34235ef3bf1d7bf3773aeac"},
@@ -70,9 +73,11 @@
   "phoenix_pubsub_redis": {:hex, :phoenix_pubsub_redis, "3.0.1", "d4d856b1e57a21358e448543e1d091e07e83403dde4383b8be04ed9d2c201cbc", [:mix], [{:phoenix_pubsub, "~> 2.0", [hex: :phoenix_pubsub, repo: "hexpm", optional: false]}, {:poolboy, "~> 1.5.1 or ~> 1.6", [hex: :poolboy, repo: "hexpm", optional: false]}, {:redix, "~> 0.10.0 or ~> 1.0", [hex: :redix, repo: "hexpm", optional: false]}], "hexpm", "0b36a17ff6e9a56159f8df8933d62b5c1f0695eae995a02e0c86c035ace6a309"},
   "phoenix_template": {:hex, :phoenix_template, "1.0.4", "e2092c132f3b5e5b2d49c96695342eb36d0ed514c5b252a77048d5969330d639", [:mix], [{:phoenix_html, "~> 2.14.2 or ~> 3.0 or ~> 4.0", [hex: :phoenix_html, repo: "hexpm", optional: true]}], "hexpm", "2c0c81f0e5c6753faf5cca2f229c9709919aba34fab866d3bc05060c9c444206"},
   "plug": {:hex, :plug, "1.18.1", "5067f26f7745b7e31bc3368bc1a2b818b9779faa959b49c934c17730efc911cf", [:mix], [{:mime, "~> 1.0 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:plug_crypto, "~> 1.1.1 or ~> 1.2 or ~> 2.0", [hex: :plug_crypto, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4.3 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "57a57db70df2b422b564437d2d33cf8d33cd16339c1edb190cd11b1a3a546cc2"},
+  "plug_cowboy": {:hex, :plug_cowboy, "2.7.4", "729c752d17cf364e2b8da5bdb34fb5804f56251e88bb602aff48ae0bd8673d11", [:mix], [{:cowboy, "~> 2.7", [hex: :cowboy, repo: "hexpm", optional: false]}, {:cowboy_telemetry, "~> 0.3", [hex: :cowboy_telemetry, repo: "hexpm", optional: false]}, {:plug, "~> 1.14", [hex: :plug, repo: "hexpm", optional: false]}], "hexpm", "9b85632bd7012615bae0a5d70084deb1b25d2bcbb32cab82d1e9a1e023168aa3"},
   "plug_crypto": {:hex, :plug_crypto, "2.1.1", "19bda8184399cb24afa10be734f84a16ea0a2bc65054e23a62bb10f06bc89491", [:mix], [], "hexpm", "6470bce6ffe41c8bd497612ffde1a7e4af67f36a15eea5f921af71cf3e11247c"},
   "poolboy": {:hex, :poolboy, "1.5.2", "392b007a1693a64540cead79830443abf5762f5d30cf50bc95cb2c1aaafa006b", [:rebar3], [], "hexpm", "dad79704ce5440f3d5a3681c8590b9dc25d1a561e8f5a9c995281012860901e3"},
   "postgrex": {:hex, :postgrex, "0.20.0", "363ed03ab4757f6bc47942eff7720640795eb557e1935951c1626f0d303a3aed", [:mix], [{:db_connection, "~> 2.1", [hex: :db_connection, repo: "hexpm", optional: false]}, {:decimal, "~> 1.5 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: true]}, {:table, "~> 0.1.0", [hex: :table, repo: "hexpm", optional: true]}], "hexpm", "d36ef8b36f323d29505314f704e21a1a038e2dc387c6409ee0cd24144e187c0f"},
+  "ranch": {:hex, :ranch, "2.2.0", "25528f82bc8d7c6152c57666ca99ec716510fe0925cb188172f41ce93117b1b0", [:make, :rebar3], [], "hexpm", "fa0b99a1780c80218a4197a59ea8d3bdae32fbff7e88527d7d8a4787eff4f8e7"},
   "redix": {:hex, :redix, "1.5.2", "ab854435a663f01ce7b7847f42f5da067eea7a3a10c0a9d560fa52038fd7ab48", [:mix], [{:castore, "~> 0.1.0 or ~> 1.0", [hex: :castore, repo: "hexpm", optional: true]}, {:nimble_options, "~> 0.5.0 or ~> 1.0", [hex: :nimble_options, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4.0 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "78538d184231a5d6912f20567d76a49d1be7d3fca0e1aaaa20f4df8e1142dcb8"},
   "req": {:hex, :req, "0.5.15", "662020efb6ea60b9f0e0fac9be88cd7558b53fe51155a2d9899de594f9906ba9", [:mix], [{:brotli, "~> 0.3.1", [hex: :brotli, repo: "hexpm", optional: true]}, {:ezstd, "~> 1.0", [hex: :ezstd, repo: "hexpm", optional: true]}, {:finch, "~> 0.17", [hex: :finch, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}, {:mime, "~> 2.0.6 or ~> 2.1", [hex: :mime, repo: "hexpm", optional: false]}, {:nimble_csv, "~> 1.0", [hex: :nimble_csv, repo: "hexpm", optional: true]}, {:plug, "~> 1.0", [hex: :plug, repo: "hexpm", optional: true]}], "hexpm", "a6513a35fad65467893ced9785457e91693352c70b58bbc045b47e5eb2ef0c53"},
   "resend": {:hex, :resend, "0.4.4", "f80c6efb6f5d1043f57a1ae1e02cd366a562cac6338097aca38675c7ebe94156", [:mix], [{:hackney, "~> 1.9", [hex: :hackney, repo: "hexpm", optional: false]}, {:swoosh, "~> 1.3", [hex: :swoosh, repo: "hexpm", optional: false]}, {:tesla, "~> 1.5", [hex: :tesla, repo: "hexpm", optional: false]}], "hexpm", "7dab4e8ae395e8ea984e4402988cc9e02b13739707deef127d8f14d181cb88ed"},
@@ -90,6 +95,8 @@
   "tailwind": {:hex, :tailwind, "0.3.1", "a89d2835c580748c7a975ad7dd3f2ea5e63216dc16d44f9df492fbd12c094bed", [:mix], [], "hexpm", "98a45febdf4a87bc26682e1171acdedd6317d0919953c353fcd1b4f9f4b676a2"},
   "telemetry": {:hex, :telemetry, "1.3.0", "fedebbae410d715cf8e7062c96a1ef32ec22e764197f70cda73d82778d61e7a2", [:rebar3], [], "hexpm", "7015fc8919dbe63764f4b4b87a95b7c0996bd539e0d499be6ec9d7f3875b79e6"},
   "telemetry_metrics": {:hex, :telemetry_metrics, "1.1.0", "5bd5f3b5637e0abea0426b947e3ce5dd304f8b3bc6617039e2b5a008adc02f8f", [:mix], [{:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "e7b79e8ddfde70adb6db8a6623d1778ec66401f366e9a8f5dd0955c56bc8ce67"},
+  "telemetry_metrics_prometheus": {:hex, :telemetry_metrics_prometheus, "1.1.0", "1cc23e932c1ef9aa3b91db257ead31ea58d53229d407e059b29bb962c1505a13", [:mix], [{:plug_cowboy, "~> 2.1", [hex: :plug_cowboy, repo: "hexpm", optional: false]}, {:telemetry_metrics_prometheus_core, "~> 1.0", [hex: :telemetry_metrics_prometheus_core, repo: "hexpm", optional: false]}], "hexpm", "d43b3659b3244da44fe0275b717701542365d4519b79d9ce895b9719c1ce4d26"},
+  "telemetry_metrics_prometheus_core": {:hex, :telemetry_metrics_prometheus_core, "1.2.1", "c9755987d7b959b557084e6990990cb96a50d6482c683fb9622a63837f3cd3d8", [:mix], [{:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}, {:telemetry_metrics, "~> 0.6 or ~> 1.0", [hex: :telemetry_metrics, repo: "hexpm", optional: false]}], "hexpm", "5e2c599da4983c4f88a33e9571f1458bf98b0cf6ba930f1dc3a6e8cf45d5afb6"},
   "telemetry_poller": {:hex, :telemetry_poller, "1.3.0", "d5c46420126b5ac2d72bc6580fb4f537d35e851cc0f8dbd571acf6d6e10f5ec7", [:rebar3], [{:telemetry, "~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "51f18bed7128544a50f75897db9974436ea9bfba560420b646af27a9a9b35211"},
   "tesla": {:hex, :tesla, "1.14.3", "b27ba2814cc08b5c4eb5f0245120198542cd023f575c490fa14447ae6763ea8d", [:mix], [{:castore, "~> 0.1 or ~> 1.0", [hex: :castore, repo: "hexpm", optional: true]}, {:exjsx, ">= 3.0.0", [hex: :exjsx, repo: "hexpm", optional: true]}, {:finch, "~> 0.13", [hex: :finch, repo: "hexpm", optional: true]}, {:fuse, "~> 2.4", [hex: :fuse, repo: "hexpm", optional: true]}, {:gun, ">= 1.0.0", [hex: :gun, repo: "hexpm", optional: true]}, {:hackney, "~> 1.21", [hex: :hackney, repo: "hexpm", optional: true]}, {:ibrowse, "4.4.2", [hex: :ibrowse, repo: "hexpm", optional: true]}, {:jason, ">= 1.0.0", [hex: :jason, repo: "hexpm", optional: true]}, {:mime, "~> 1.0 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:mint, "~> 1.0", [hex: :mint, repo: "hexpm", optional: true]}, {:mox, "~> 1.0", [hex: :mox, repo: "hexpm", optional: true]}, {:msgpax, "~> 2.3", [hex: :msgpax, repo: "hexpm", optional: true]}, {:poison, ">= 1.0.0", [hex: :poison, repo: "hexpm", optional: true]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: true]}], "hexpm", "4f419aa2ab908cff43a117d3b5de99edad8fd54690211cbbdc7d2941c03a1458"},
   "text_diff": {:hex, :text_diff, "0.1.0", "1caf3175e11a53a9a139bc9339bd607c47b9e376b073d4571c031913317fecaa", [:mix], [], "hexpm", "d1ffaaecab338e49357b6daa82e435f877e0649041ace7755583a0ea3362dbd7"},