tests: do secondary download in live migration test

test_runner/fixtures/pageserver/http.py

@@ -326,6 +326,10 @@ class PageserverHttpClient(requests.Session):
         res = self.post(f"http://localhost:{self.port}/v1/tenant/{tenant_id}/heatmap_upload")
         self.verbose_error(res)
 
+    def tenant_secondary_download(self, tenant_id: TenantId):
+        res = self.post(f"http://localhost:{self.port}/v1/tenant/{tenant_id}/secondary/download")
+        self.verbose_error(res)
+
     def set_tenant_config(self, tenant_id: TenantId, config: dict[str, Any]):
         assert "tenant_id" not in config.keys()
         res = self.put(

test_runner/regress/test_pageserver_secondary.py

@@ -255,6 +255,9 @@ def test_live_migration(neon_env_builder: NeonEnvBuilder):
         flush_ms=5000,
     )
 
+    # Encourage the new location to download while still in secondary mode
+    pageserver_b.http_client().tenant_secondary_download(tenant_id)
+
     migrated_generation = env.attachment_service.attach_hook_issue(tenant_id, pageserver_b.id)
     log.info(f"Acquired generation {migrated_generation} for destination pageserver")
     assert migrated_generation == initial_generation + 1
@@ -262,8 +265,6 @@ def test_live_migration(neon_env_builder: NeonEnvBuilder):
     # Writes and reads still work in AttachedStale.
     workload.validate(pageserver_a.id)
 
-    # TODO: call into secondary mode API hooks to do an upload/download sync
-
     # Generate some more dirty writes: we expect the origin to ingest WAL in
     # in AttachedStale
     workload.churn_rows(64, pageserver_a.id, upload=False)