Authorize Klarna Checkout

POST

api

domains

{domain}

express

klarna

authorize

Authorize Klarna Checkout

curl --request POST \
  --url https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --header 'x-firmly-authorization: <x-firmly-authorization>' \
  --data '
{
  "attributes": {
    "authorization_token": "<string>"
  }
}
'

import requests

url = "https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize"

payload = { "attributes": { "authorization_token": "<string>" } }
headers = {
    "x-firmly-authorization": "<x-firmly-authorization>",
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {
    'x-firmly-authorization': '<x-firmly-authorization>',
    Authorization: 'Bearer <token>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({attributes: {authorization_token: '<string>'}})
};

fetch('https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'attributes' => [
        'authorization_token' => '<string>'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json",
    "x-firmly-authorization: <x-firmly-authorization>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize"

	payload := strings.NewReader("{\n  \"attributes\": {\n    \"authorization_token\": \"<string>\"\n  }\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("x-firmly-authorization", "<x-firmly-authorization>")
	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize")
  .header("x-firmly-authorization", "<x-firmly-authorization>")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"attributes\": {\n    \"authorization_token\": \"<string>\"\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["x-firmly-authorization"] = '<x-firmly-authorization>'
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"attributes\": {\n    \"authorization_token\": \"<string>\"\n  }\n}"

response = http.request(request)
puts response.read_body

{
  "cart_id": "<string>",
  "line_items": [
    {}
  ],
  "payment_method": {
    "payment_type": "<string>",
    "attributes": {
      "session_id": "<string>",
      "authorization_token": "<string>"
    }
  },
  "shipping_info": {},
  "total": {},
  "sub_total": {},
  "tax": {}
}

Overview

After the customer authorizes payment in the Klarna widget (client-side), this endpoint confirms the authorization with Firmly. It stores the authorization_token in the session and returns the cart with the confirmed Klarna payment method.

Authentication

string

required

Device authentication token from Browser Session

Path Parameters

string

required

The merchant domain (e.g., “merchant.example.com”)

Request Body

object

required

Klarna authorization details

Show Attributes

string

required

The authorization token received from the Klarna Payments SDK after the customer approves payment. Obtained from the Klarna.Payments.authorize() callback.

Response

Returns the cart with the confirmed Klarna payment method.

string

Unique identifier for the cart

array

Array of items in the cart

object

Confirmed Klarna payment method

Show Payment Method

string

Always "Klarna" for this gateway

object

Klarna authorization details

Show Attributes

string

Klarna payment session identifier (from start checkout)

string

The confirmed authorization token

object

Delivery address details

object

Grand total including all costs

object

Subtotal before shipping and tax

object

Tax amount

Code Example

// After Klarna.Payments.authorize() callback returns authorization_token
const response = await fetch(
  'https://cc.firmly.work/api/v1/domains/merchant.example.com/express/klarna/authorize',
  {
    method: 'POST',
    headers: {
      'x-firmly-authorization': authToken,
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({
      attributes: {
        authorization_token: 'klarna_auth_token_from_widget'
      }
    })
  }
);

const cart = await response.json();
// Payment is now authorized, proceed to complete order

import requests

response = requests.post(
    'https://cc.firmly.work/api/v1/domains/merchant.example.com/express/klarna/authorize',
    headers={
        'x-firmly-authorization': auth_token,
        'Content-Type': 'application/json'
    },
    json={
        'attributes': {
            'authorization_token': 'klarna_auth_token_from_widget'
        }
    }
)

cart = response.json()

curl -X POST https://cc.firmly.work/api/v1/domains/merchant.example.com/express/klarna/authorize \
  -H "x-firmly-authorization: YOUR_AUTH_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"attributes": {"authorization_token": "klarna_auth_token_from_widget"}}'

Response Example

{
  "cart_id": "9cf76530-1344-420f-9ca6-c7a96fb6db45",
  "line_items": [
    {
      "line_item_id": "3e66bef5-43f5-4a80-8957-91c5c8233163",
      "sku": "MT12",
      "quantity": 1,
      "description": "Cassius Sparring Tank",
      "price": {
        "currency": "USD",
        "value": 18,
        "number": 1800,
        "symbol": "$"
      },
      "line_price": {
        "currency": "USD",
        "value": 18,
        "number": 1800,
        "symbol": "$"
      }
    }
  ],
  "payment_method": {
    "payment_type": "Klarna",
    "attributes": {
      "session_id": "kp_abc123def456",
      "authorization_token": "klarna_auth_token_from_widget"
    }
  },
  "shipping_info": {
    "first_name": "John",
    "last_name": "Smith",
    "email": "john@example.com",
    "phone": "2065551212",
    "address1": "123 Main St",
    "city": "Seattle",
    "state_or_province": "WA",
    "country": "US",
    "postal_code": "98101"
  },
  "total": {
    "currency": "USD",
    "value": 30,
    "number": 3000,
    "symbol": "$"
  },
  "sub_total": {
    "currency": "USD",
    "value": 18,
    "number": 1800,
    "symbol": "$"
  },
  "tax": {
    "currency": "USD",
    "value": 2,
    "number": 200,
    "symbol": "$"
  }
}

Error Responses

Code	Description
`ErrorCartNotFound`	No active cart for this domain
`ErrorBadRequest`	Missing `authorization_token` in request body
`ErrorGatewayNotFound`	Klarna is not enabled for this merchant
`ErrorPrecondition`	Precondition failed (e.g., cart state invalid)
`ErrorSubmitExpressCheckout`	Authorization failed at the merchant

Start Klarna Checkout - Create Klarna session first
Complete Klarna Order - Finalize the order

⌘I

Authorize Klarna Checkout

curl --request POST \
  --url https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --header 'x-firmly-authorization: <x-firmly-authorization>' \
  --data '
{
  "attributes": {
    "authorization_token": "<string>"
  }
}
'

import requests

url = "https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize"

payload = { "attributes": { "authorization_token": "<string>" } }
headers = {
    "x-firmly-authorization": "<x-firmly-authorization>",
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {
    'x-firmly-authorization': '<x-firmly-authorization>',
    Authorization: 'Bearer <token>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({attributes: {authorization_token: '<string>'}})
};

fetch('https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'attributes' => [
        'authorization_token' => '<string>'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json",
    "x-firmly-authorization: <x-firmly-authorization>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize"

	payload := strings.NewReader("{\n  \"attributes\": {\n    \"authorization_token\": \"<string>\"\n  }\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("x-firmly-authorization", "<x-firmly-authorization>")
	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize")
  .header("x-firmly-authorization", "<x-firmly-authorization>")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"attributes\": {\n    \"authorization_token\": \"<string>\"\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://cc.firmly.work/api/v1/domains/{domain}/express/klarna/authorize")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["x-firmly-authorization"] = '<x-firmly-authorization>'
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"attributes\": {\n    \"authorization_token\": \"<string>\"\n  }\n}"

response = http.request(request)
puts response.read_body

{
  "cart_id": "<string>",
  "line_items": [
    {}
  ],
  "payment_method": {
    "payment_type": "<string>",
    "attributes": {
      "session_id": "<string>",
      "authorization_token": "<string>"
    }
  },
  "shipping_info": {},
  "total": {},
  "sub_total": {},
  "tax": {}
}

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Authorize Klarna Checkout

Overview

Authentication

Path Parameters

Request Body

Response

Code Example

Response Example

Error Responses

​Overview

​Authentication

​Path Parameters

​Request Body

​Response

​Code Example

​Response Example

​Error Responses

​Related Endpoints

Overview

Authentication

Path Parameters

Request Body

Response

Code Example

Response Example

Error Responses

Related Endpoints