如何将字典放入 JSON？

Question

I'm working with a REST API, and I need to return a JSON with my values to it. However, I need the items of the payload variable to show all the items inside the cart_item .

I have this:

payload = {
    "items": [],
}

I tried this, but I don't know how I would put this inside the items of the payload:

for cart_item in cart_items:
    item = [
        {
            "reference_id": f"{cart_item.sku}",
            "name": f"{cart_item.product.name}",
            "quantity": cart_item.quantity,
            "unit_amount": cart_item.product.price
        },
     ]

I need you to get back to me:

payload = {
    "items": [ 
        {
            "reference_id": "SKU49FS20DD",
            "name": "Produto 1",
            "quantity": 1,
            "unit_amount": 130
        },
        {
            "reference_id": "SKU42920SSD",
            "name": "Produto 2",
            "quantity": 1,
            "unit_amount": 100
        }
    ],
}

response = requests.request(
    "POST",
    url,
    headers=headers,
    json=payload
)

I don't know if I would need to pass what's in JSON to the dictionary to change and then send it to JSON again.

Answer 1

You're just missing the " append() " method on a list, and the conversion from Python list & dict to a JSON string :

 from json import dumps

 items_dict = []
 for cart_item in cart_items:
            items_dict.append({
                "reference_id": f"{cart_item.sku}",
                "name": f"{cart_item.product.name}",
                "quantity": cart_item.quantity,
                "unit_amount": cart_item.product.price
             })

payload = {
    'items': items_dict
}

# And if you want a JSON string as output
print(dumps(payload))

But you don't need a string to the "json" argument in requests.post, so you can keep your

response = requests.request(
    "POST",
    url, 
    headers=headers,
    json=payload
)

Answer 2

Instead of trying to create one item at a time, just populate payload['items'] directly, using a comprehension:

payload['items'] = [
    {
        'reference_id': cart_item.sku,
        'name': cart_item.product.name,
        'quantity': cart_item.quantity,
        'unit_amount': cart_item.product.price 
    }
    for cart_item in cart_items
]

Another possible improvement is about requests . Instead of using requests.requests('POST'...) , you can use requests.post(...) .

And finally, if the API really needs json to have a valid JSON string, use json.dumps to convert it.

Putting all together:

import requests
import json

payload['items'] = [
    {
        'reference_id': cart_item.sku,
        'name': cart_item.product.name,
        'quantity': cart_item.quantity,
        'unit_amount': cart_item.product.price 
    }
    for cart_item in cart_items
]

response = requests.post(
    url,
    headers=headers,
    json=json.dumps(payload)
)

Even though I'm almost a hundred percent sure requests.post() will do the right thing if you just pass the payload as is in json=payload .