curl --request POST \
  --url https://api.opencals.com/storefront/cart/checkout/start \
  --header 'Content-Type: application/json' \
  --header 'X-Cart-Id: <x-cart-id>' \
  --data '
{
  "provider": "stripe",
  "customer": {
    "customerId": "123e4567-e89b-12d3-a456-426614174004"
  }
}
'

import requests

url = "https://api.opencals.com/storefront/cart/checkout/start"

payload = {
    "provider": "stripe",
    "customer": { "customerId": "123e4567-e89b-12d3-a456-426614174004" }
}
headers = {
    "X-Cart-Id": "<x-cart-id>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {'X-Cart-Id': '<x-cart-id>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    provider: 'stripe',
    customer: {customerId: '123e4567-e89b-12d3-a456-426614174004'}
  })
};

fetch('https://api.opencals.com/storefront/cart/checkout/start', 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://api.opencals.com/storefront/cart/checkout/start",
  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([
    'provider' => 'stripe',
    'customer' => [
        'customerId' => '123e4567-e89b-12d3-a456-426614174004'
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "X-Cart-Id: <x-cart-id>"
  ],
]);

$response = curl_exec($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://api.opencals.com/storefront/cart/checkout/start"

	payload := strings.NewReader("{\n  \"provider\": \"stripe\",\n  \"customer\": {\n    \"customerId\": \"123e4567-e89b-12d3-a456-426614174004\"\n  }\n}")

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

	req.Header.Add("X-Cart-Id", "<x-cart-id>")
	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://api.opencals.com/storefront/cart/checkout/start")
  .header("X-Cart-Id", "<x-cart-id>")
  .header("Content-Type", "application/json")
  .body("{\n  \"provider\": \"stripe\",\n  \"customer\": {\n    \"customerId\": \"123e4567-e89b-12d3-a456-426614174004\"\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.opencals.com/storefront/cart/checkout/start")

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

request = Net::HTTP::Post.new(url)
request["X-Cart-Id"] = '<x-cart-id>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"provider\": \"stripe\",\n  \"customer\": {\n    \"customerId\": \"123e4567-e89b-12d3-a456-426614174004\"\n  }\n}"

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

{
  "paymentId": "<string>",
  "cart": {
    "id": "<string>",
    "storeId": "<string>",
    "customerId": "<string>",
    "paymentCurrencyCode": "<string>",
    "taxesIncluded": true,
    "expiresAt": "2023-11-07T05:31:56Z",
    "extensionsCount": 123,
    "appliedDiscountCode": "<string>",
    "createdAt": "2023-11-07T05:31:56Z",
    "updatedAt": "2023-11-07T05:31:56Z",
    "subtotal": 100,
    "totalTax": 20,
    "total": 120,
    "appliedDiscounts": [
      {
        "id": "<string>",
        "title": "<string>",
        "totalAmount": 123,
        "code": "<string>"
      }
    ],
    "customer": {
      "id": "123e4567-e89b-12d3-a456-426614174000",
      "externalId": "1234567890",
      "firstName": "John",
      "lastName": "Smith",
      "email": "john.smith@example.com",
      "phone": "+12135550123",
      "password": "<string>",
      "storeId": "store-uuid",
      "language": "en",
      "createdAt": "2023-01-15T10:30:00Z",
      "updatedAt": "2023-02-20T14:15:00Z",
      "emailVerifiedAt": "2023-01-02T00:00:00Z",
      "deletedAt": "2023-06-03T09:45:00Z",
      "isEmailVerified": true,
      "isPasswordSet": true
    },
    "items": [
      {
        "id": "<string>",
        "cartId": "<string>",
        "appointmentId": "<string>",
        "originalUnitPrice": 123,
        "discountedUnitPrice": 123,
        "unitTaxAmount": 123,
        "quantity": 1,
        "createdAt": "2023-11-07T05:31:56Z",
        "updatedAt": "2023-11-07T05:31:56Z",
        "deletedAt": "2023-11-07T05:31:56Z",
        "discounts": [
          {
            "discountId": "<string>",
            "title": "<string>",
            "amountPerUnit": 123,
            "value": 123
          }
        ],
        "lineSubtotal": 100,
        "lineTax": 20,
        "appointment": {
          "id": "123e4567-e89b-12d3-a456-426614174000",
          "name": "1001",
          "productId": "123e4567-e89b-12d3-a456-426614174001",
          "staffMemberId": "123e4567-e89b-12d3-a456-426614174002",
          "locationId": "123e4567-e89b-12d3-a456-426614174003",
          "storeId": "123e4567-e89b-12d3-a456-426614174004",
          "customerId": "123e4567-e89b-12d3-a456-426614174005",
          "externalOrderId": "12345678",
          "externalOrderName": "#1001",
          "from": "2023-06-15T09:00:00Z",
          "to": "2023-06-15T10:00:00Z",
          "addressLine1": "123 Main Street",
          "addressLine2": "Suite 456",
          "city": "New York",
          "state": "NY",
          "postalCode": "10001",
          "country": "USA",
          "status": "scheduled",
          "internalNote": "Customer requested extra attention for specific needs",
          "createdBy": "customer",
          "reminderSentAt": "2023-06-14T09:00:00Z",
          "numberOfAttendees": 1,
          "createdAt": "2023-06-01T10:30:00Z",
          "updatedAt": "2023-06-02T14:15:00Z",
          "deletedAt": "2023-06-03T09:45:00Z",
          "product": {
            "id": "123e4567-e89b-12d3-a456-426614174000",
            "productId": "123e4567-e89b-12d3-a456-426614174000",
            "externalId": "1234567890",
            "externalVariantId": "9876543210",
            "storeId": "123e4567-e89b-12d3-a456-426614174001",
            "slug": "haircut-basic",
            "scheduleId": "<string>",
            "productPoolId": "<string>",
            "title": "Haircut Service",
            "variantTitle": "Short Hair",
            "description": "<string>",
            "imageId": "<string>",
            "color": "BLUE",
            "price": 250,
            "taxable": false,
            "duration": 3600,
            "allowCustomDuration": false,
            "maxDuration": -1,
            "maxAttendees": 1,
            "maxGuests": 123,
            "allowGuests": false,
            "allowCustomerReschedule": false,
            "allowCustomerCancel": false,
            "rescheduleGap": 123,
            "cancelGap": 123,
            "beforeGap": 123,
            "afterGap": 123,
            "fixedTimes": false,
            "fixedStartTime": "09:00:00",
            "fixedEndTime": "17:00:00",
            "advanceScheduleThreshold": 0,
            "sendConfirmationEmail": true,
            "sendReminderEmail": false,
            "sendFeedbackEmail": false,
            "skipCheckout": false,
            "status": "ACTIVE",
            "createdAt": "<string>",
            "updatedAt": "<string>",
            "deletedAt": "<string>",
            "image": {
              "id": "123e4567-e89b-12d3-a456-426614174000",
              "externalId": "img_123456",
              "url": "https://storage.example.com/images/product-image.jpg",
              "filename": "product-image.jpg",
              "mime": "image/jpeg",
              "createdAt": "2023-01-01T12:00:00Z",
              "updatedAt": "2023-01-02T12:00:00Z",
              "deletedAt": "2023-01-03T12:00:00Z",
              "storeId": "store-uuid"
            },
            "schedule": {
              "id": "123e4567-e89b-12d3-a456-426614174000",
              "storeId": "123e4567-e89b-12d3-a456-426614174001",
              "name": "Standard Business Hours",
              "timezone": "UTC",
              "scheduleGap": "every-15-minutes",
              "appointmentsGap": 900,
              "advanceScheduleDays": 60,
              "availabilityType": "recurring",
              "status": "active",
              "createdAt": "2023-01-20T08:30:00Z",
              "updatedAt": "2023-02-15T14:20:00Z",
              "deletedAt": "2023-06-03T09:45:00Z"
            }
          },
          "staffMember": {
            "id": "123e4567-e89b-12d3-a456-426614174000",
            "storeId": "123e4567-e89b-12d3-a456-426614174111",
            "userId": "user-uuid",
            "scheduleId": "123e4567-e89b-12d3-a456-426614174000",
            "imageId": "123e4567-e89b-12d3-a456-426614174000",
            "firstName": "John",
            "lastName": "Doe",
            "email": "john.doe@example.com",
            "slug": "mike",
            "refreshToken": "abc123xyz456",
            "createdAt": "2025-05-01T12:00:00Z",
            "updatedAt": "2025-05-15T14:30:00Z",
            "deletedAt": "2025-06-01T09:15:00Z",
            "image": {
              "id": "123e4567-e89b-12d3-a456-426614174000",
              "externalId": "img_123456",
              "url": "https://storage.example.com/images/product-image.jpg",
              "filename": "product-image.jpg",
              "mime": "image/jpeg",
              "createdAt": "2023-01-01T12:00:00Z",
              "updatedAt": "2023-01-02T12:00:00Z",
              "deletedAt": "2023-01-03T12:00:00Z",
              "storeId": "store-uuid"
            },
            "schedule": {
              "id": "123e4567-e89b-12d3-a456-426614174000",
              "storeId": "123e4567-e89b-12d3-a456-426614174001",
              "name": "Standard Business Hours",
              "timezone": "UTC",
              "scheduleGap": "every-15-minutes",
              "appointmentsGap": 900,
              "advanceScheduleDays": 60,
              "availabilityType": "recurring",
              "status": "active",
              "createdAt": "2023-01-20T08:30:00Z",
              "updatedAt": "2023-02-15T14:20:00Z",
              "deletedAt": "2023-06-03T09:45:00Z"
            }
          },
          "location": {
            "id": "123e4567-e89b-12d3-a456-426614174000",
            "storeId": "123e4567-e89b-12d3-a456-426614174001",
            "scheduleId": "123e4567-e89b-12d3-a456-426614174002",
            "title": "Main Office",
            "description": "Our main downtown office location with 3 treatment rooms",
            "slug": "new-york",
            "type": "physical",
            "link": "https://zoom.us/j/123456789",
            "addressLine1": "123 Main Street",
            "addressLine2": "Suite 200",
            "city": "San Francisco",
            "state": "CA",
            "postalCode": "94105",
            "country": "United States",
            "addressPlaceId": "ChIJIQBpAG2ahYAR_6128GcTUEo",
            "latitude": 37.4224764,
            "longitude": -122.0842499,
            "createdAt": "2023-01-20T08:30:00Z",
            "updatedAt": "2023-02-15T14:20:00Z",
            "deletedAt": "2023-03-10T11:45:00Z",
            "address": "<string>",
            "schedule": {
              "id": "123e4567-e89b-12d3-a456-426614174000",
              "storeId": "123e4567-e89b-12d3-a456-426614174001",
              "name": "Standard Business Hours",
              "timezone": "UTC",
              "scheduleGap": "every-15-minutes",
              "appointmentsGap": 900,
              "advanceScheduleDays": 60,
              "availabilityType": "recurring",
              "status": "active",
              "createdAt": "2023-01-20T08:30:00Z",
              "updatedAt": "2023-02-15T14:20:00Z",
              "deletedAt": "2023-06-03T09:45:00Z"
            }
          }
        },
        "addOnItems": [
          {
            "id": "<string>",
            "cartId": "<string>",
            "cartItemId": "<string>",
            "addOnId": "<string>",
            "originalUnitPrice": 123,
            "discountedUnitPrice": 123,
            "unitTaxAmount": 123,
            "quantity": 1,
            "createdAt": "2023-11-07T05:31:56Z",
            "updatedAt": "2023-11-07T05:31:56Z",
            "deletedAt": "2023-11-07T05:31:56Z",
            "discounts": [
              {
                "discountId": "<string>",
                "title": "<string>",
                "amountPerUnit": 123,
                "value": 123
              }
            ],
            "addOn": {
              "id": "123e4567-e89b-12d3-a456-426614174000",
              "externalId": "1234567890",
              "externalVariantId": "9876543210",
              "storeId": "123e4567-e89b-12d3-a456-426614174001",
              "slug": "child-seat",
              "title": "Child Seat",
              "description": "<string>",
              "imageId": "<string>",
              "color": "slate",
              "price": 15,
              "taxable": true,
              "durationMultiplied": false,
              "maxQuantity": 4,
              "status": "active",
              "createdAt": "<string>",
              "updatedAt": "<string>",
              "deletedAt": "<string>",
              "image": {
                "id": "123e4567-e89b-12d3-a456-426614174000",
                "externalId": "img_123456",
                "url": "https://storage.example.com/images/product-image.jpg",
                "filename": "product-image.jpg",
                "mime": "image/jpeg",
                "createdAt": "2023-01-01T12:00:00Z",
                "updatedAt": "2023-01-02T12:00:00Z",
                "deletedAt": "2023-01-03T12:00:00Z",
                "storeId": "store-uuid"
              }
            }
          }
        ]
      }
    ],
    "payments": [
      {
        "id": "<string>",
        "cartId": "<string>",
        "orderId": "<string>",
        "provider": {},
        "providerReference": "<string>",
        "amount": 123,
        "currency": "<string>",
        "capturedAmount": 123,
        "authorizedUntil": "2023-11-07T05:31:56Z",
        "clientSecret": "<string>",
        "createdAt": "2023-11-07T05:31:56Z",
        "updatedAt": "2023-11-07T05:31:56Z"
      }
    ]
  },
  "invalidItemIds": [
    "<string>"
  ],
  "revivedItemIds": [
    "<string>"
  ],
  "clientSecret": "<string>",
  "redirectUrl": "<string>",
  "stripeAccountId": "<string>",
  "publishableKey": "<string>",
  "discountCodeCleared": true
}