log "Custom/smtp_connection_time" metric in newrelic

app/config.py

@@ -7,6 +7,7 @@ from ast import literal_eval
 from typing import Callable
 from urllib.parse import urlparse
 
+import newrelic.agent
 from dotenv import load_dotenv
 
 SHA1 = subprocess.getoutput("git rev-parse HEAD")
@@ -402,6 +403,12 @@ except Exception:
 HIBP_API_KEYS = sl_getenv("HIBP_API_KEYS", list) or []
 
 NEWRELIC_CONFIG_PATH = os.environ.get("NEWRELIC_CONFIG_PATH")
+newrelic_app = None
+if NEWRELIC_CONFIG_PATH:
+    newrelic.agent.initialize(NEWRELIC_CONFIG_PATH)
+
+    newrelic_app = newrelic.agent.register_application()
+
 
 POSTMASTER = os.environ.get("POSTMASTER")
 

app/email_utils.py

@@ -17,6 +17,7 @@ from typing import Tuple, List, Optional, Union
 
 import arrow
 import dkim
+import newrelic.agent
 import re2 as re
 import spf
 from cachetools import cached, TTLCache
@@ -53,6 +54,7 @@ from app.config import (
     TEMP_DIR,
     ALIAS_AUTOMATIC_DISABLE,
     RSPAMD_SIGN_DKIM,
+    newrelic_app,
 )
 from app.db import Session
 from app.dns_utils import get_mx_domains
@@ -1307,7 +1309,11 @@ def sl_sendmail(
             if POSTFIX_SUBMISSION_TLS:
                 smtp.starttls()
 
-            LOG.d("getting a smtp connection takes seconds %s", time.time() - start)
+            elapsed = time.time() - start
+            LOG.d("getting a smtp connection takes seconds %s", elapsed)
+            newrelic.agent.record_custom_metric(
+                "Custom/smtp_connection_time", elapsed, newrelic_app
+            )
 
             # smtp.send_message has UnicodeEncodeError
             # encode message raw directly instead

email_handler.py

@@ -78,13 +78,13 @@ from app.config import (
     TRANSACTIONAL_BOUNCE_SUFFIX,
     ENABLE_SPAM_ASSASSIN,
     BOUNCE_PREFIX_FOR_REPLY_PHASE,
-    NEWRELIC_CONFIG_PATH,
     POSTMASTER,
     ALERT_HOTMAIL_COMPLAINT,
     ALERT_YAHOO_COMPLAINT,
     ALERT_HOTMAIL_COMPLAINT_TRANSACTIONAL,
     ALERT_HOTMAIL_COMPLAINT_REPLY_PHASE,
     OLD_UNSUBSCRIBER,
+    newrelic_app,
 )
 from app.db import Session
 from app.email import status, headers
@@ -145,12 +145,6 @@ from app.utils import sanitize_email
 from init_app import load_pgp_public_keys
 from server import create_light_app
 
-newrelic_app = None
-if NEWRELIC_CONFIG_PATH:
-    newrelic.agent.initialize(NEWRELIC_CONFIG_PATH)
-
-    newrelic_app = newrelic.agent.register_application()
-
 
 def get_or_create_contact(from_header: str, mail_from: str, alias: Alias) -> Contact:
     """