django/core/serializers/jsonl.py

"""
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
from django.core.serializers.python import 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 from PythonDeserializer([json.loads(line)], **options)
        except (GeneratorExit, DeserializationError):
            raise
        except Exception as exc:
            raise DeserializationError() from exc