如何创建sqlalchemy到json

Question

我有一个sqlalchemy结果

labels = session.query(
         LabelsData, 
         LabelsData.id, 
         LabelsData.name, 
         LabelsData.color
         ).filter(LabelsData.deleted==False).all()

我想将此结果转换为JSON,但我该怎么做呢？

Answer 1

看起来您的LabelsData对象是SQLAlchemy模型.您需要在将其转储到JSON之前对其进行序列化.这是一个简短的示例,它从LabelsData对象中提取所有列,并将查询结果转换为JSON:

from json import dumps
from sqlalchemy.orm import class_mapper

def serialize(model):
  """Transforms a model into a dictionary which can be dumped to JSON."""
  # first we get the names of all the columns on your model
  columns = [c.key for c in class_mapper(model.__class__).columns]
  # then we return their values in a dict
  return dict((c, getattr(model, c)) for c in columns)

# we can then use this for your particular example
serialized_labels = [
  serialize(label)
  for label in session.query(LabelsData).filter(LabelsData.deleted == False)
]
your_json = dumps(serialized_labels)