From da7a27552a5215b075ba0a600961c81a79bee7c0 Mon Sep 17 00:00:00 2001
From: Simon Cruanes <simon.cruanes.2007@m4x.org>
Date: Thu, 18 Jan 2024 21:11:58 -0500
Subject: [PATCH] wip: tests for prometheus

---
 tests/prometheus/dune            |  4 ++++
 tests/prometheus/t_prom.expected | 22 ++++++++++++++++++++++
 tests/prometheus/t_prom.ml       | 23 +++++++++++++++++++++++
 3 files changed, 49 insertions(+)
 create mode 100644 tests/prometheus/dune
 create mode 100644 tests/prometheus/t_prom.expected
 create mode 100644 tests/prometheus/t_prom.ml

diff --git a/tests/prometheus/dune b/tests/prometheus/dune
new file mode 100644
index 00000000..da921019
--- /dev/null
+++ b/tests/prometheus/dune
@@ -0,0 +1,4 @@
+
+(test
+  (name t_prom)
+  (libraries tiny_httpd.prometheus))
diff --git a/tests/prometheus/t_prom.expected b/tests/prometheus/t_prom.expected
new file mode 100644
index 00000000..590b6c82
--- /dev/null
+++ b/tests/prometheus/t_prom.expected
@@ -0,0 +1,22 @@
+==== first try ====
+```
+# TYPE yolo_gauge gauge
+yolo_gauge{level="max"} 2525
+# HELP t_c2 more awesome than c1
+# TYPE t_c2 counter
+t_c2 1
+# TYPE t_c1 counter
+t_c1 42
+
+```
+==== second try====
+```
+# TYPE yolo_gauge gauge
+yolo_gauge{level="max"} 42000
+# HELP t_c2 more awesome than c1
+# TYPE t_c2 counter
+t_c2 2
+# TYPE t_c1 counter
+t_c1 53
+
+```
diff --git a/tests/prometheus/t_prom.ml b/tests/prometheus/t_prom.ml
new file mode 100644
index 00000000..8e9fe8b5
--- /dev/null
+++ b/tests/prometheus/t_prom.ml
@@ -0,0 +1,23 @@
+module P = Tiny_httpd_prometheus
+
+let pf = Printf.printf
+let reg = P.Registry.create ()
+let c1 = P.Counter.create reg "t_c1"
+let c2 = P.Counter.create reg "t_c2" ~descr:"more awesome than c1"
+let g1 = P.Gauge.create reg ~tags:[ "level", "max" ] "yolo_gauge"
+
+let () =
+  print_endline "==== first try ====";
+  P.Counter.inc_by c1 42;
+  P.Counter.inc c2;
+  P.Gauge.set g1 2525;
+
+  pf "```\n%s\n```\n" @@ P.Registry.emit_str reg
+
+let () =
+  print_endline "==== second try====";
+  P.Counter.inc_by c1 11;
+  P.Counter.inc c2;
+  P.Gauge.set g1 42_000;
+
+  pf "```\n%s\n```\n" @@ P.Registry.emit_str reg