将类对象转换为JSON Python - EasyPost - Django

I am building a JsonResponse view in Django 1.7 via Python 2.7.9 for tracking requests made through the EasyPost API. The view:

我正在通过Python 2.7.9在Django 1.7中构建一个JsonResponse视图，用于跟踪通过EasyPost API发出的请求。风景：

def TrackingTable(request, trackingnumber):
    easypost.api_key = 'xxxxxxxxxxxxxxxxxxx'

    tracker = easypost.Tracker.create(
          tracking_code='EZ3000000003',
          carrier="UPS"
      )

    tracking = tracker['tracking_details']

    return JsonResponse({"tracking":tracking, "url":request.get_full_path})

When this wasn't working I tried to see if the issue was related to Json. So i went in manually and tried to pull out JSON values since the EasyPost API (and response object) shows JSON as the output:

当这不起作用时，我试着看看问题是否与Json有关。所以我手动进入并尝试提取JSON值，因为EasyPost API（和响应对象）显示JSON作为输出：

easypost.api_key = 'xxxxxxxxxxxxxxxxxxx'

tracker = easypost.Tracker.create(
      tracking_code='EZ3000000003',
      carrier="UPS"
  )


>>> tracker
<Tracker Tracker at 0x7f467982be50> JSON: {
  "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
  "carrier": "UPS", 
  "created_at": "2015-03-18T15:48:43Z", 
  "est_delivery_date": "2014-08-27T00:00:00Z", 
  "id": "trk_qufcxYmC", 
  "mode": "test", 
  "object": "Tracker", 
  "shipment_id": null, 
  "signed_by": null, 
  "status": "out_for_delivery", 
  "tracking_code": "EZ3000000003", 
  "tracking_details": [
    {
      "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
      "datetime": "2014-08-21T14:24:00Z", 
      "message": "BILLING INFORMATION RECEIVED", 
      "object": "TrackingDetail", 
      "status": "pre_transit", 
      "tracking_location": {
        "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
        "city": null, 
        "country": null, 
        "object": "TrackingLocation", 
        "state": null, 
        "zip": null
      }
    }, 
    {
      "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
      "datetime": "2014-08-21T14:48:00Z", 
      "message": "ORIGIN SCAN", 
      "object": "TrackingDetail", 
      "status": "in_transit", 
      "tracking_location": {
        "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
        "city": "SOUTH SAN FRANCISCO", 
        "country": "US", 
        "object": "TrackingLocation", 
        "state": "CA", 
        "zip": null
      }
    }, 
    {
      "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
      "datetime": "2014-08-22T08:51:00Z", 
      "message": "DEPARTURE SCAN", 
      "object": "TrackingDetail", 
      "status": "in_transit", 
      "tracking_location": {
        "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
        "city": "SOUTH SAN FRANCISCO", 
        "country": "US", 
        "object": "TrackingLocation", 
        "state": "CA", 
        "zip": null
      }
    }, 
    {
      "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
      "datetime": "2014-08-23T09:31:00Z", 
      "message": "ARRIVAL SCAN", 
      "object": "TrackingDetail", 
      "status": "in_transit", 
      "tracking_location": {
        "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
        "city": "SAN FRANCISCO", 
        "country": "US", 
        "object": "TrackingLocation", 
        "state": "CA", 
        "zip": null
      }
    }, 
    {
      "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
      "datetime": "2014-08-24T08:10:00Z", 
      "message": "OUT FOR DELIVERY", 
      "object": "TrackingDetail", 
      "status": "out_for_delivery", 
      "tracking_location": {
        "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
        "city": "SAN FRANCISCO", 
        "country": "US", 
        "object": "TrackingLocation", 
        "state": "CA", 
        "zip": null
      }
    }
  ], 
  "updated_at": "2015-03-18T15:48:43Z", 
  "weight": 17.6
}>

"tracker" is a class object

“tracker”是一个类对象

>>> print type(tracker)  
<class 'easypost.Tracker'>

Attempt to convert class to dicitonary:

尝试将类转换为dicitonary：

>>> this = dict(tracker) 
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.7/site-packages/easypost/__init__.py", line 359, in keys
    return self._values.keys()
AttributeError: 'set' object has no attribute 'keys'

Attempt to dump to JSON:

尝试转储到JSON：

>>> json.dumps(tracker)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.7/json/__init__.py", line 243, in dumps
    return _default_encoder.encode(obj)
  File "/usr/local/lib/python2.7/json/encoder.py", line 207, in encode
    chunks = self.iterencode(o, _one_shot=True)
  File "/usr/local/lib/python2.7/json/encoder.py", line 270, in iterencode
    return _iterencode(o, 0)
  File "/usr/local/lib/python2.7/json/encoder.py", line 184, in default
    raise TypeError(repr(o) + " is not JSON serializable")
TypeError: <Tracker Tracker at 0x7f467982be50> JSON: {
  "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
  "carrier": "UPS", 
  "created_at": "2015-03-18T15:48:43Z", 
  "est_delivery_date": "2014-08-27T00:00:00Z", 
  "id": "trk_qufcxYmC", 
  "mode": "test", 
  "object": "Tracker", 
  "shipment_id": null, 
  "signed_by": null, 
  "status": "out_for_delivery", 
  "tracking_code": "EZ3000000003", 
  "tracking_details": [
    {
      "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
      "datetime": "2014-08-21T14:24:00Z", 
      "message": "BILLING INFORMATION RECEIVED", 
      "object": "TrackingDetail", 
      "status": "pre_transit", 
      "tracking_location": {
        "api_key": "IAiiSCSBtBXPKiaVmcc1wQ", 
        "city": null, 
        "country": null, 
        "object": "TrackingLocation", 
        "state": null, 
        "zip": null
      }
    }, 
# Removed same data as above to make shorter
  "updated_at": "2015-03-18T15:48:43Z", 
  "weight": 17.6
} is not JSON serializable
>>>

It looks like the nested JSON in "tracking_details" is causing errors to be thrown, any help on how to convert the data into a JSON Object?

看起来“tracking_details”中的嵌套JSON会导致抛出错误，有关如何将数据转换为JSON对象的任何帮助？

3 个解决方案

#1

So the quickest way I have been able to solve this has beeb via jsonpickle.

因此，我能够通过jsonpickle解决这个问题的最快捷方式。

Example from jsonpickle:

jsonpickle的示例：

import jsonpickle

frozen = jsonpickle.encode(obj)
Use jsonpickle to recreate a Python object from a JSON string:

thawed = jsonpickle.decode(frozen)
Warning Loading a JSON string from an untrusted source represents a potential security vulnerability. jsonpickle makes no attempt to sanitize the input.
The new object has the same type and data, but essentially is now a copy of the original.

assert obj.name == thawed.name
If you will never need to load (regenerate the Python class from JSON), you can pass in the keyword unpicklable=False to prevent extra information from being added to JSON:

oneway = jsonpickle.encode(obj, unpicklable=False)
result = jsonpickle.decode(oneway)
assert obj.name == result['name'] == 'Awesome'

Applied to this situation:

适用于这种情况：

>>>tracker_encode = jsonpickle.encode(tracker, unpicklable=False)
>>>tracker_decoded= jsonpickle.decode(tracker_encode)
>>> print type(tracker_decoded)
<type 'dict'>
>>> for x in tracker_decoded:
...     print x
... 
status
object
weight
tracking_details
shipment_id
created_at
_immutable_values
_transient_values
updated_at
_unsaved_values
tracking_code
carrier
mode
_values
est_delivery_date
_retrieve_params
api_key
id
signed_by

This encoded the entire output to a dictionary that I am then able to convert to json using the return JsonResponse({"tracking":tracking_decoded, "url":request.get_full_path})

这将整个输出编码为一个字典，然后我可以使用返回JsonResponse（{“tracking”：tracking_decoded，“url”：request.get_full_path}）将其转换为json。

Result using Postman: 将类对象转换为JSON Python - EasyPost - Django

使用Postman的结果：

#2

I think you need a Serializer!

我想你需要一个Serializer！

Check marshmallow at http://marshmallow.readthedocs.org !

检查http://marshmallow.readthedocs.org上的棉花糖！

I've been using this to JSON serialize my objects!

我一直用它来JSON序列化我的对象！

You will need to write something like:

你需要写一些类似的东西：

SomeObjectSerializer(Schema):
    class Meta:
      fields = ('api_key', 'id', 'someotherattributes')

and then when you want to serialize your objects just call:

然后当你想要序列化你的对象时，只需调用：

obj = Model(**args)
SomeObjectSerializer(obj).data

and this should be giving you a JSON serialized output

这应该是给你一个JSON序列化输出

#3

From the source, you can call tracker.to_dict()

从源代码，您可以调用tracker.to_dict（）

The to_dict method is available on all EasyPost objects in the client.

to_dict方法可用于客户端中的所有EasyPost对象。

#1