Fix microbatch dbt list --output JSON

Currently, running this command on a project containing a microbatch
model results in an error, as microbatch models require a datetime
value in their config which cannot be serialized by the default JSON
serializer.

There already exists a custom JSON serializer within the dbt-core
project that converts datetime to ISO string format. This change uses
the above serializer to resolve the error.

.changes/unreleased/Fixes-20250107-105738.yaml

@@ -0,0 +1,6 @@
+kind: Fixes
+body: Fix microbatch dbt list --output json
+time: 2025-01-07T10:57:38.985761+01:00
+custom:
+    Author: internetcoffeephone
+    Issue: "11098"

core/dbt/task/list.py

@@ -17,6 +17,7 @@
 from dbt.node_types import NodeType
 from dbt.task.base import resource_types_from_args
 from dbt.task.runnable import GraphRunnableTask
+from dbt.utils import JSONEncoder
 from dbt_common.events.contextvars import task_contextvars
 from dbt_common.events.functions import fire_event, warn_or_error
 from dbt_common.events.types import PrintEvent
@@ -142,7 +143,8 @@ def generate_json(self):
                         if self.args.output_keys
                         else k in self.ALLOWED_KEYS
                     )
-                }
+                },
+                cls=JSONEncoder,
             )
 
     def generate_paths(self) -> Iterator[str]:

tests/functional/microbatch/test_microbatch.py

@@ -1,3 +1,4 @@
+import json
 from unittest import mock
 
 import pytest
@@ -15,6 +16,7 @@
     MicrobatchMacroOutsideOfBatchesDeprecation,
     MicrobatchModelNoEventTimeInputs,
 )
+from dbt.tests.fixtures.project import TestProjInfo
 from dbt.tests.util import (
     get_artifact,
     patch_microbatch_end_time,
@@ -328,6 +330,17 @@ def test_run_with_event_time(self, project):
         )
         self.assert_row_count(project, "microbatch_model", 1)
 
+    def test_list_output_json(self, project: TestProjInfo):
+        """Test whether the command `dbt list --output json` works"""
+        model_catcher = EventCatcher(event_to_catch=LogModelResult)
+        batch_catcher = EventCatcher(event_to_catch=LogBatchResult)
+
+        _, microbatch_json = run_dbt(
+            ["list", "--output", "json"], callbacks=[model_catcher.catch, batch_catcher.catch]
+        )
+        microbatch_dict = json.loads(microbatch_json)
+        assert microbatch_dict["config"]["begin"] == "2020-01-01T00:00:00"
+
 
 class TestMicrobatchCLIBuild(TestMicrobatchCLI):
     CLI_COMMAND_NAME = "build"