From 942b2f937c275b5f3cf9589856e15c7f3875ec00 Mon Sep 17 00:00:00 2001
From: Andy Balaam <andy.balaam@matrix.org>
Date: Tue, 16 Jul 2024 13:30:10 +0100
Subject: [PATCH] logging: Extract debug log code into a separate function.

This reduces the work we do to calculate changed devices etc. when DEBUG
logging is not enabled, but more importantly (to me) it makes clear
that this code is only used for logging.
---
 .../src/identities/manager.rs                 | 76 +++++++++++--------
 1 file changed, 44 insertions(+), 32 deletions(-)

diff --git a/crates/matrix-sdk-crypto/src/identities/manager.rs b/crates/matrix-sdk-crypto/src/identities/manager.rs
index 7e84199d7..c43a856aa 100644
--- a/crates/matrix-sdk-crypto/src/identities/manager.rs
+++ b/crates/matrix-sdk-crypto/src/identities/manager.rs
@@ -27,7 +27,7 @@ use ruma::{
     OwnedServerName, OwnedTransactionId, OwnedUserId, ServerName, TransactionId, UserId,
 };
 use tokio::sync::Mutex;
-use tracing::{debug, info, instrument, trace, warn};
+use tracing::{debug, enabled, info, instrument, trace, warn, Level};
 
 use crate::{
     error::OlmResult,
@@ -182,37 +182,9 @@ impl IdentityManager {
                 .await?;
         }
 
-        #[allow(unknown_lints, clippy::unwrap_or_default)] // false positive
-        let changed_devices = devices.changed.iter().fold(BTreeMap::new(), |mut acc, d| {
-            acc.entry(d.user_id()).or_insert_with(BTreeSet::new).insert(d.device_id());
-            acc
-        });
-
-        #[allow(unknown_lints, clippy::unwrap_or_default)] // false positive
-        let new_devices = devices.new.iter().fold(BTreeMap::new(), |mut acc, d| {
-            acc.entry(d.user_id()).or_insert_with(BTreeSet::new).insert(d.device_id());
-            acc
-        });
-
-        #[allow(unknown_lints, clippy::unwrap_or_default)] // false positive
-        let deleted_devices = devices.deleted.iter().fold(BTreeMap::new(), |mut acc, d| {
-            acc.entry(d.user_id()).or_insert_with(BTreeSet::new).insert(d.device_id());
-            acc
-        });
-
-        let new_identities = identities.new.iter().map(|i| i.user_id()).collect::<BTreeSet<_>>();
-        let changed_identities =
-            identities.changed.iter().map(|i| i.user_id()).collect::<BTreeSet<_>>();
-
-        debug!(
-            ?request_id,
-            ?new_devices,
-            ?changed_devices,
-            ?deleted_devices,
-            ?new_identities,
-            ?changed_identities,
-            "Finished handling of the `/keys/query` response"
-        );
+        if enabled!(Level::DEBUG) {
+            debug_log_keys_query_response(&devices, &identities, request_id);
+        }
 
         Ok((devices, identities))
     }
@@ -1011,6 +983,46 @@ impl IdentityManager {
     }
 }
 
+/// Log information about what changed after processing a /keys/query response.
+/// Only does anything if the DEBUG log level is enabled.
+fn debug_log_keys_query_response(
+    devices: &DeviceChanges,
+    identities: &IdentityChanges,
+    request_id: &TransactionId,
+) {
+    #[allow(unknown_lints, clippy::unwrap_or_default)] // false positive
+    let changed_devices = devices.changed.iter().fold(BTreeMap::new(), |mut acc, d| {
+        acc.entry(d.user_id()).or_insert_with(BTreeSet::new).insert(d.device_id());
+        acc
+    });
+
+    #[allow(unknown_lints, clippy::unwrap_or_default)] // false positive
+    let new_devices = devices.new.iter().fold(BTreeMap::new(), |mut acc, d| {
+        acc.entry(d.user_id()).or_insert_with(BTreeSet::new).insert(d.device_id());
+        acc
+    });
+
+    #[allow(unknown_lints, clippy::unwrap_or_default)] // false positive
+    let deleted_devices = devices.deleted.iter().fold(BTreeMap::new(), |mut acc, d| {
+        acc.entry(d.user_id()).or_insert_with(BTreeSet::new).insert(d.device_id());
+        acc
+    });
+
+    let new_identities = identities.new.iter().map(|i| i.user_id()).collect::<BTreeSet<_>>();
+    let changed_identities =
+        identities.changed.iter().map(|i| i.user_id()).collect::<BTreeSet<_>>();
+
+    debug!(
+        ?request_id,
+        ?new_devices,
+        ?changed_devices,
+        ?deleted_devices,
+        ?new_identities,
+        ?changed_identities,
+        "Finished handling of the `/keys/query` response"
+    );
+}
+
 #[cfg(any(test, feature = "testing"))]
 #[allow(dead_code)]
 pub(crate) mod testing {