Add nonci_accounts metric

Calculating this with PromQL is not easy
due to interpolation.

Also add HELP and TYPE metadata for each metric.

CHANGELOG.md

@@ -40,6 +40,9 @@
 - DKIM-sign Content-Type and oversign all signed headers
   ([#296](https://github.com/deltachat/chatmail/pull/296))
 
+- Add nonci_accounts metric
+  ([#347](https://github.com/deltachat/chatmail/pull/347))
+
 ## 1.3.0 - 2024-06-06
 
 - don't check necessary DNS records on cmdeploy init anymore

chatmaild/src/chatmaild/metrics.py

@@ -1,6 +1,5 @@
 #!/usr/bin/env python3
 import sys
-import time
 from pathlib import Path
 
 
@@ -16,9 +15,15 @@ def main(vmail_dir=None):
         if path.name[:3] in ("ci-", "ac_"):
             ci_accounts += 1
 
-    timestamp = int(time.time() * 1000)
+    print("# HELP total number of accounts")
-    print(f"accounts {accounts} {timestamp}")
+    print("# TYPE accounts gauge")
-    print(f"ci_accounts {ci_accounts} {timestamp}")
+    print(f"accounts {accounts}")
+    print("# HELP number of CI accounts")
+    print("# TYPE ci_accounts gauge")
+    print(f"ci_accounts {ci_accounts}")
+    print("# HELP number of non-CI accounts")
+    print("# TYPE nonci_accounts gauge")
+    print(f"nonci_accounts {accounts - ci_accounts}")
 
 
 if __name__ == "__main__":

chatmaild/src/chatmaild/tests/test_metrics.py

@@ -8,9 +8,10 @@ def test_main(tmp_path, capsys):
     out, _ = capsys.readouterr()
     d = {}
     for line in out.split("\n"):
-        if line.strip():
+        if line.strip() and not line.startswith("#"):
-            name, num, _ = line.split()
+            name, num = line.split()
             d[name] = int(num)
 
     assert d["accounts"] == 4
     assert d["ci_accounts"] == 3
+    assert d["nonci_accounts"] == 1