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().

typeerror the json object must be str bytes or bytearray not response

Here is an example of how the error occurs.

main.py

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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.

main.py

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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()

We called the json() method on the Response object to parse it into a native Python object before accessing any of its keys.

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.

main.py

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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.

main.py

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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.

Python	JSON
dict	object
list, tuple	array
str	string
int, float, int and float derived Enums	number
True	true
False	false
None	null

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

main.py

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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.

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

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

Borislav Hadzhiev