From d6d6d06179a2460eadec7b93fb0422fe90985285 Mon Sep 17 00:00:00 2001
From: Daisuke Taniwaki <daisuketaniwaki@gmail.com>
Date: Wed, 22 Apr 2026 12:41:21 +0900
Subject: [PATCH 1/2] perf: cache parsed manifest in APIDbtRunner

Reuse the parsed manifest across sequential dbt run-operation calls
instead of re-parsing it on every invocation. This reduces edr report
overhead from ~18 manifest parses down to 1.
---
 elementary/clients/dbt/api_dbt_runner.py | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/elementary/clients/dbt/api_dbt_runner.py b/elementary/clients/dbt/api_dbt_runner.py
index 7dcf729ae..1235f557c 100644
--- a/elementary/clients/dbt/api_dbt_runner.py
+++ b/elementary/clients/dbt/api_dbt_runner.py
@@ -24,6 +24,10 @@ class APIDbtCommandResult(DbtCommandResult):
 
 
 class APIDbtRunner(CommandLineDbtRunner):
+    def __init__(self, *args, **kwargs):
+        self._manifest = None
+        super().__init__(*args, **kwargs)
+
     def _inner_run_command(
         self,
         dbt_command_args: List[str],
@@ -45,9 +49,11 @@ def collect_dbt_command_logs(event):
                 dbt_logs.append(event_dump)
 
         with env_vars_context(self.env_vars):
-            dbt = dbtRunner(callbacks=[collect_dbt_command_logs])
+            dbt = dbtRunner(manifest=self._manifest, callbacks=[collect_dbt_command_logs])
             with with_chdir(self.project_dir):
                 res: dbtRunnerResult = dbt.invoke(dbt_command_args)
+        if self._manifest is None and res.success:
+            self._manifest = dbt.manifest
         output = "\n".join(dbt_logs) or None
         # Surface the exception text so that transient-error detection in
         # _inner_run_command_with_retries can match against it.  The dbt

From ccb3fe8b68dd8e95ace594e916e8ccccc0d7ac2a Mon Sep 17 00:00:00 2001
From: Daisuke Taniwaki <daisuketaniwaki@gmail.com>
Date: Wed, 22 Apr 2026 13:12:22 +0900
Subject: [PATCH 2/2] test: add unit tests for APIDbtRunner manifest caching

Cover three scenarios:
- manifest is cached after the first successful invocation
- manifest is not cached when invocation fails
- cached manifest is reused on subsequent calls
---
 .../clients/dbt_runner/test_api_dbt_runner.py | 89 +++++++++++++++++++
 1 file changed, 89 insertions(+)
 create mode 100644 tests/unit/clients/dbt_runner/test_api_dbt_runner.py

diff --git a/tests/unit/clients/dbt_runner/test_api_dbt_runner.py b/tests/unit/clients/dbt_runner/test_api_dbt_runner.py
new file mode 100644
index 000000000..5a825ef76
--- /dev/null
+++ b/tests/unit/clients/dbt_runner/test_api_dbt_runner.py
@@ -0,0 +1,89 @@
+from contextlib import contextmanager
+from unittest import mock
+
+from dbt.cli.main import dbtRunnerResult
+
+from elementary.clients.dbt.api_dbt_runner import APIDbtRunner
+
+
+def _make_result(success=True, exception=None):
+    return dbtRunnerResult(
+        success=success,
+        result=None,
+        exception=exception,
+    )
+
+
+def _make_runner():
+    runner = APIDbtRunner.__new__(APIDbtRunner)
+    runner._manifest = None
+    runner.project_dir = "/tmp/fake"
+    runner.env_vars = None
+    runner.raise_on_failure = False
+    return runner
+
+
+@contextmanager
+def _noop_context(*args, **kwargs):
+    yield
+
+
+_PATCH_CHDIR = mock.patch("elementary.clients.dbt.api_dbt_runner.with_chdir", _noop_context)
+_PATCH_ENV = mock.patch("elementary.clients.dbt.api_dbt_runner.env_vars_context", _noop_context)
+
+
+@_PATCH_ENV
+@_PATCH_CHDIR
+@mock.patch("elementary.clients.dbt.api_dbt_runner.dbtRunner")
+def test_manifest_cached_after_first_success(mock_dbt_runner_cls):
+    fake_manifest = object()
+    mock_instance = mock.MagicMock()
+    mock_instance.invoke.return_value = _make_result(success=True)
+    mock_instance.manifest = fake_manifest
+    mock_dbt_runner_cls.return_value = mock_instance
+
+    runner = _make_runner()
+    runner._inner_run_command(["run-operation", "foo"], quiet=True, log_output=False, log_format="json")
+
+    assert runner._manifest is fake_manifest
+    mock_dbt_runner_cls.assert_called_once_with(manifest=None, callbacks=mock.ANY)
+
+
+@_PATCH_ENV
+@_PATCH_CHDIR
+@mock.patch("elementary.clients.dbt.api_dbt_runner.dbtRunner")
+def test_manifest_not_cached_on_failure(mock_dbt_runner_cls):
+    mock_instance = mock.MagicMock()
+    mock_instance.invoke.return_value = _make_result(success=False)
+    mock_instance.manifest = object()
+    mock_dbt_runner_cls.return_value = mock_instance
+
+    runner = _make_runner()
+    runner._inner_run_command(["run-operation", "foo"], quiet=True, log_output=False, log_format="json")
+
+    assert runner._manifest is None
+
+
+@_PATCH_ENV
+@_PATCH_CHDIR
+@mock.patch("elementary.clients.dbt.api_dbt_runner.dbtRunner")
+def test_cached_manifest_reused_on_subsequent_calls(mock_dbt_runner_cls):
+    fake_manifest = object()
+    mock_instance = mock.MagicMock()
+    mock_instance.invoke.return_value = _make_result(success=True)
+    mock_instance.manifest = fake_manifest
+    mock_dbt_runner_cls.return_value = mock_instance
+
+    runner = _make_runner()
+
+    runner._inner_run_command(["run-operation", "foo"], quiet=True, log_output=False, log_format="json")
+    assert runner._manifest is fake_manifest
+
+    new_manifest = object()
+    mock_instance.manifest = new_manifest
+    mock_dbt_runner_cls.reset_mock()
+
+    runner._inner_run_command(["run-operation", "bar"], quiet=True, log_output=False, log_format="json")
+
+    mock_dbt_runner_cls.assert_called_once_with(manifest=fake_manifest, callbacks=mock.ANY)
+    assert runner._manifest is fake_manifest