Fixed #30190 -- Added JSONL serializer.

2 files changed, 58 insertions, 0 deletions

diff --git a/django/core/serializers/__init__.py b/django/core/serializers/__init__.py
index 5e16a7560f..793f6dc2bd 100644
--- a/django/core/serializers/__init__.py
+++ b/django/core/serializers/__init__.py
@@ -28,6 +28,7 @@ BUILTIN_SERIALIZERS = {
     "python": "django.core.serializers.python",
     "json": "django.core.serializers.json",
     "yaml": "django.core.serializers.pyyaml",
+    "jsonl": "django.core.serializers.jsonl",
 }
 
 _serializers = {}
diff --git a/django/core/serializers/jsonl.py b/django/core/serializers/jsonl.py
new file mode 100644
index 0000000000..ff0d9eb605
--- /dev/null
+++ b/django/core/serializers/jsonl.py
@@ -0,0 +1,57 @@
+"""
+Serialize data to/from JSON Lines
+"""
+
+import json
+
+from django.core.serializers.base import DeserializationError
+from django.core.serializers.json import DjangoJSONEncoder
+from django.core.serializers.python import (
+    Deserializer as PythonDeserializer, Serializer as PythonSerializer,
+)
+
+
+class Serializer(PythonSerializer):
+    """Convert a queryset to JSON Lines."""
+    internal_use_only = False
+
+    def _init_options(self):
+        self._current = None
+        self.json_kwargs = self.options.copy()
+        self.json_kwargs.pop('stream', None)
+        self.json_kwargs.pop('fields', None)
+        self.json_kwargs.pop('indent', None)
+        self.json_kwargs['separators'] = (',', ': ')
+        self.json_kwargs.setdefault('cls', DjangoJSONEncoder)
+        self.json_kwargs.setdefault('ensure_ascii', False)
+
+    def start_serialization(self):
+        self._init_options()
+
+    def end_object(self, obj):
+        # self._current has the field data
+        json.dump(self.get_dump_object(obj), self.stream, **self.json_kwargs)
+        self.stream.write("\n")
+        self._current = None
+
+    def getvalue(self):
+        # Grandparent super
+        return super(PythonSerializer, self).getvalue()
+
+
+def Deserializer(stream_or_string, **options):
+    """Deserialize a stream or string of JSON data."""
+    if isinstance(stream_or_string, bytes):
+        stream_or_string = stream_or_string.decode()
+    if isinstance(stream_or_string, (bytes, str)):
+        stream_or_string = stream_or_string.split("\n")
+
+    for line in stream_or_string:
+        if not line.strip():
+            continue
+        try:
+            yield list(PythonDeserializer([json.loads(line), ], **options))[0]
+        except (GeneratorExit, DeserializationError):
+            raise
+        except Exception as exc:
+            raise DeserializationError() from exc