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> For a complete documentation index, see https://docs.getdial.ai/llms.txt.
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# Start a subscription checkout

POST https://getdial.ai/api/v1/billing/checkout/subscription
Content-Type: application/json

Returns an embedded Stripe Checkout `clientSecret` to subscribe the account for the given `interval`. Quantity is set server-side to the account's current phone-number count (one unit per number) — Dial doesn't subscribe a subset. Coverage begins when the invoice is paid. Not available during impersonation.

Reference: https://docs.getdial.ai/api-reference/rest-api/billing/create-subscription-checkout

## OpenAPI Specification

```yaml
openapi: 3.1.0
info:
  title: rest
  version: 1.0.0
paths:
  /api/v1/billing/checkout/subscription:
    post:
      operationId: create-subscription-checkout
      summary: Start a subscription checkout
      description: >-
        Returns an embedded Stripe Checkout `clientSecret` to subscribe the
        account for the given `interval`. Quantity is set server-side to the
        account's current phone-number count (one unit per number) — Dial
        doesn't subscribe a subset. Coverage begins when the invoice is paid.
        Not available during impersonation.
      tags:
        - subpackage_billing
      parameters:
        - name: Authorization
          in: header
          description: 'Your Dial API key, sent as `Authorization: Bearer sk_live_...`'
          required: true
          schema:
            type: string
      responses:
        '200':
          description: Embedded Checkout client secret.
          content:
            application/json:
              schema:
                $ref: >-
                  #/components/schemas/Billing_createSubscriptionCheckout_Response_200
        '400':
          description: The request body failed validation.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
        '401':
          description: Missing or invalid API key.
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Error'
      requestBody:
        content:
          application/json:
            schema:
              type: object
              properties:
                interval:
                  $ref: >-
                    #/components/schemas/ApiV1BillingCheckoutSubscriptionPostRequestBodyContentApplicationJsonSchemaInterval
                returnUrl:
                  type: string
                  format: uri
                  description: >-
                    Where Checkout returns after completion. Defaults to the
                    dashboard billing page.
              required:
                - interval
servers:
  - url: https://getdial.ai
    description: Dial API (provisional host)
components:
  schemas:
    ApiV1BillingCheckoutSubscriptionPostRequestBodyContentApplicationJsonSchemaInterval:
      type: string
      enum:
        - monthly
        - annual
      title: >-
        ApiV1BillingCheckoutSubscriptionPostRequestBodyContentApplicationJsonSchemaInterval
    Billing_createSubscriptionCheckout_Response_200:
      type: object
      properties:
        clientSecret:
          type: string
      title: Billing_createSubscriptionCheckout_Response_200
    ErrorError:
      oneOf:
        - type: string
        - type: object
          additionalProperties:
            description: Any type
      description: An error message, or a validation-error object for 400 responses.
      title: ErrorError
    Error:
      type: object
      properties:
        error:
          $ref: '#/components/schemas/ErrorError'
          description: An error message, or a validation-error object for 400 responses.
      title: Error
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      description: 'Your Dial API key, sent as `Authorization: Bearer sk_live_...`'

```

## Examples



**Request**

```json
{
  "interval": "monthly"
}
```

**Response**

```json
{
  "clientSecret": "pi_3Kq1X2Lz0a1b2c3d4e5f6g7h_secret_9x8y7z6w5v4u3t2s1r0q"
}
```

**SDK Code**

```python
import requests

url = "https://getdial.ai/api/v1/billing/checkout/subscription"

payload = { "interval": "monthly" }
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.json())
```

```javascript
const url = 'https://getdial.ai/api/v1/billing/checkout/subscription';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: '{"interval":"monthly"}'
};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```

```go
package main

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

func main() {

	url := "https://getdial.ai/api/v1/billing/checkout/subscription"

	payload := strings.NewReader("{\n  \"interval\": \"monthly\"\n}")

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

	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(res)
	fmt.Println(string(body))

}
```

```ruby
require 'uri'
require 'net/http'

url = URI("https://getdial.ai/api/v1/billing/checkout/subscription")

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

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"interval\": \"monthly\"\n}"

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

```java
import com.mashape.unirest.http.HttpResponse;
import com.mashape.unirest.http.Unirest;

HttpResponse<String> response = Unirest.post("https://getdial.ai/api/v1/billing/checkout/subscription")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"interval\": \"monthly\"\n}")
  .asString();
```

```php
<?php
require_once('vendor/autoload.php');

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://getdial.ai/api/v1/billing/checkout/subscription', [
  'body' => '{
  "interval": "monthly"
}',
  'headers' => [
    'Authorization' => 'Bearer <token>',
    'Content-Type' => 'application/json',
  ],
]);

echo $response->getBody();
```

```csharp
using RestSharp;

var client = new RestClient("https://getdial.ai/api/v1/billing/checkout/subscription");
var request = new RestRequest(Method.POST);
request.AddHeader("Authorization", "Bearer <token>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"interval\": \"monthly\"\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = [
  "Authorization": "Bearer <token>",
  "Content-Type": "application/json"
]
let parameters = ["interval": "monthly"] as [String : Any]

let postData = JSONSerialization.data(withJSONObject: parameters, options: [])

let request = NSMutableURLRequest(url: NSURL(string: "https://getdial.ai/api/v1/billing/checkout/subscription")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "POST"
request.allHTTPHeaderFields = headers
request.httpBody = postData as Data

let session = URLSession.shared
let dataTask = session.dataTask(with: request as URLRequest, completionHandler: { (data, response, error) -> Void in
  if (error != nil) {
    print(error as Any)
  } else {
    let httpResponse = response as? HTTPURLResponse
    print(httpResponse)
  }
})

dataTask.resume()
```