✨ Add support for datetimes

Author: ManuDeBuck

jsonfilelogger/custom_encoder.py

@@ -0,0 +1,11 @@
+from typing import Any
+import datetime
+import json
+
+
+class CustomEncoder(json.JSONEncoder):
+    def default(self, o: Any) -> Any:
+        if isinstance(o, datetime.datetime):
+            return str(o)
+        else:
+            return super().default(o)

jsonfilelogger/logger.py

@@ -1,6 +1,7 @@
 import os
 import json
 import time
+from .custom_encoder import CustomEncoder
 
 
 class LogBase:
@@ -113,7 +114,7 @@ def flush(self):
                 # set ',' for previously added entry
                 file.write(",\n")
             # write new entries
-            file.write(",\n".join([json.dumps(el) for el in self.log_buffer]))
+            file.write(",\n".join([json.dumps(el, cls=CustomEncoder) for el in self.log_buffer]))
             # always close file to have correct json syntax
             file.write("\n]\n")
 

tests/test_logger.py

@@ -1,3 +1,4 @@
+import datetime
 import os
 import pytest
 import glob
@@ -33,7 +34,24 @@ def test_writer_and_reader():
         reader.assert_file_exists()
 
 
-def test_writer_and_reader_with_datetime():
+def test_writer_and_reader_with_datetime_value():
+    writer = LogWriter(threshold=1)
+    writer.reset()
+    writer.log({"datetime": datetime.datetime.fromisoformat("2021-11-17 18:23:22.483962")})
+    assert os.path.exists("./log.json")
+    reader = LogReader()
+    data = reader.retrieve()
+    assert len(data) == 1
+    assert data == [{"datetime": "2021-11-17 18:23:22.483962"}]
+    reader.reset()
+    data = reader.retrieve()
+    assert len(data) == 0
+    reader.remove()
+    with pytest.raises(Exception):
+        reader.assert_file_exists()
+
+
+def test_writer_and_reader_with_datetime_filename():
     writer = LogWriter.with_datetime(threshold=2)
     writer.reset()
     writer.log({"test": 1, "this": "logger", "with": True, "all": 1.337, "kinds": ["of", "values"]})