conditionally import deepdiff (#164)

only import deepdiff when needed

dbt_common/record.py

@@ -10,7 +10,6 @@
 import json
 import os
 
-from deepdiff import DeepDiff  # type: ignore
 from enum import Enum
 from typing import Any, Callable, Dict, List, Mapping, Optional, Type
 
@@ -52,6 +51,11 @@ def from_dict(cls, dct: Mapping) -> "Record":
 
 class Diff:
     def __init__(self, current_recording_path: str, previous_recording_path: str) -> None:
+        # deepdiff is expensive to import, so we only do it here when we need it
+        from deepdiff import DeepDiff  # type: ignore
+
+        self.diff = DeepDiff
+
         self.current_recording_path = current_recording_path
         self.previous_recording_path = previous_recording_path
 
@@ -67,7 +71,7 @@ def diff_query_records(self, current: List, previous: List) -> Dict[str, Any]:
             if previous[i].get("result").get("table") is not None:
                 previous[i]["result"]["table"] = json.loads(previous[i]["result"]["table"])
 
-        return DeepDiff(previous, current, ignore_order=True, verbose_level=2)
+        return self.diff(previous, current, ignore_order=True, verbose_level=2)
 
     def diff_env_records(self, current: List, previous: List) -> Dict[str, Any]:
         # The mode and filepath may change.  Ignore them.
@@ -77,12 +81,12 @@ def diff_env_records(self, current: List, previous: List) -> Dict[str, Any]:
             "root[0]['result']['env']['DBT_RECORDER_MODE']",
         ]
 
-        return DeepDiff(
+        return self.diff(
             previous, current, ignore_order=True, verbose_level=2, exclude_paths=exclude_paths
         )
 
     def diff_default(self, current: List, previous: List) -> Dict[str, Any]:
-        return DeepDiff(previous, current, ignore_order=True, verbose_level=2)
+        return self.diff(previous, current, ignore_order=True, verbose_level=2)
 
     def calculate_diff(self) -> Dict[str, Any]:
         with open(self.current_recording_path) as current_recording: