From 6686367452e1321472990cc974a52fad9a2e3eb7 Mon Sep 17 00:00:00 2001
From: John Spray <john@neon.tech>
Date: Wed, 28 Feb 2024 14:22:01 +0000
Subject: [PATCH] wip

---
 control_plane/attachment_service/src/service.rs | 4 ++++
 libs/pageserver_api/src/models.rs               | 8 ++++++++
 test_runner/regress/test_sharding_service.py    | 2 +-
 3 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/control_plane/attachment_service/src/service.rs b/control_plane/attachment_service/src/service.rs
index 14cf3c8a56..3bdc387e13 100644
--- a/control_plane/attachment_service/src/service.rs
+++ b/control_plane/attachment_service/src/service.rs
@@ -1273,6 +1273,10 @@ impl Service {
                     }
                 }
 
+                // TODO: we need to recognize that this is an update, issue a DB
+                // transaction to update the shards, and _then_ apply in memory.  Need
+                // the tenant equivalent of node_configure()
+
                 shard.config = req.config.tenant_conf.clone();
                 shard.schedule(scheduler)?;
 
diff --git a/libs/pageserver_api/src/models.rs b/libs/pageserver_api/src/models.rs
index aa1a8ae487..a780c80357 100644
--- a/libs/pageserver_api/src/models.rs
+++ b/libs/pageserver_api/src/models.rs
@@ -289,6 +289,14 @@ pub struct TenantConfig {
     pub timeline_get_throttle: Option<ThrottleConfig>,
 }
 
+impl TenantConfig {
+    pub fn merge(&mut self, other: &TenantConfig) {
+        if let Some(max_lsn_wal_lag) = &other.max_lsn_wal_lag {
+            self.max_lsn_wal_lag = Some(*max_lsn_wal_lag);
+        }
+    }
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
 #[serde(tag = "kind")]
 pub enum EvictionPolicy {
diff --git a/test_runner/regress/test_sharding_service.py b/test_runner/regress/test_sharding_service.py
index 1e8a0417de..1ef5836e8b 100644
--- a/test_runner/regress/test_sharding_service.py
+++ b/test_runner/regress/test_sharding_service.py
@@ -385,7 +385,7 @@ def test_sharding_service_onboarding(
         dest_tenant_after_conf_change["generation"] == dest_tenant_before_conf_change["generation"]
     )
     dest_tenant_conf_after = dest_ps.http_client().tenant_config(tenant_id)
-    assert dest_tenant_conf_after == TenantConfig.from_json(modified_tenant_conf)
+    assert dest_tenant_conf_after.tenant_specific_overrides == modified_tenant_conf
 
     env.attachment_service.consistency_check()