The JSON object must be str, bytes or bytearray not Response

The JSON object must be str, bytes or bytearray not Response #

The Python "TypeError: the JSON object must be str, bytes or bytearray, not Response" occurs when we pass a Response object to the json.loads() method. To solve the error, call the json() method on the Response object instead, e.g. result = res.json().

Here is an example of how the error occurs.

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import json
import requests


def make_request():
    res = requests.get('https://reqres.in/api/users')

    # ⛔️ TypeError: the JSON object must be str, bytes or bytearray, not Response
    parsed = json.loads(res)


make_request()

We passed a Response object to the json.loads() method which caused the error.

To solve the error, use the json() method on the response object instead.

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import requests


def make_request():
    res = requests.get('https://reqres.in/api/users')

    # ✅ call .json() method on Response object
    parsed = res.json()

    print(parsed)
    print(type(parsed)) # 👉️ <class 'dict'>


make_request()

You should use the json() method to parse the data from all requests, not just HTTP GET.

Here is an example of a POST request with the requests module.

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import requests


def make_request():
    res = requests.post(
        'https://reqres.in/api/users',
        data={'name': 'John Smith', 'job': 'manager'}
    )

    # ✅ parse JSON response to native Python object
    data = res.json()

    # 👇️ {'name': 'John Smith', 'job': 'manager', 'id': '649', 'createdAt': '2022-05-20T10:11:23.939Z'}
    print(data)

    print(data['name']) # 👉️ "John Smith"
    print(data['job']) # 👉️ "manager"
    print(data['id']) # 649


make_request()

If you are working with a JSON string or a native Python object, make sure to use the json.loads() and json.dumps() methods.

If you need to parse a JSON string into a native Python object, you have to use the json.loads() method, and if you need to convert a Python object into a JSON string, you have to use the json.dumps() method.

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import json

json_str = r'{"name": "Alice", "age": 30}'


# ✅ parse JSON string to Python native dict
my_dict = json.loads(json_str)
print(type(my_dict))  # 👉️ <class 'dict'>

# ✅ convert Python native dict to a JSON string
my_json_str = json.dumps(my_dict)
print(type(my_json_str))  # 👉️ <class 'str'>

The json.loads() method basically helps us load a Python native object (e.g. a dictionary or a list) from a JSON string.

The json.dumps method converts a Python object to a JSON formatted string.

The JSONEncoder class supports the following objects and types by default.

If you aren't sure what type of object a variable stores, use the built-in type() class.

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my_dict = {'name': 'Alice', 'age': 30}
print(type(my_dict))  # 👉️ <class 'dict'>
print(isinstance(my_dict, dict))  # 👉️ True


my_str = 'hello world'
print(type(my_str))  # 👉️ <class 'str'>
print(isinstance(my_str, str))  # 👉️ True

The type class returns the type of an object.

The isinstance function returns True if the passed in object is an instance or a subclass of the passed in class.

Conclusion #

The Python "TypeError: the JSON object must be str, bytes or bytearray, not Response" occurs when we pass a Response object to the json.loads() method. To solve the error, call the json() method on the Response object instead, e.g. result = res.json().