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# Create an Application

POST https://YOUR_SPACE.signalwire.com/api/laml/2010-04-01/Accounts/{AccountSid}/Applications
Content-Type: application/x-www-form-urlencoded

Creates a reusable voice and messaging routing application in the account. The new Application also becomes an addressable [cXML Application](/docs/apis/rest/cxml-applications/list-cxml-applications). The cXML Applications API manages existing applications but does not create them, so create Applications here.

#### Permissions

The API token used to authenticate must have the following scope(s) enabled to make a successful request: _Voice_ or _Messaging_ or _Fax_.

[Learn more about API scopes](/docs/platform/your-signalwire-api-space).

Reference: https://signalwire.com/docs/compatibility-api/rest/applications/create-application

## Authentication

- `Authorization` header (basic auth, required) — SignalWire Basic Authentication using Project ID and API Token. The client sends HTTP requests with the Authorization header containing the word Basic followed by a space and a base64-encoded string of project_id:token. The project ID will be used as the username and the API token as the password. Example: ``` Authorization: Basic base64(project_id:token) ```

## Request

### Path parameters

- `AccountSid` (string, required) — The Account ID that has the Application.

### Body (application/x-www-form-urlencoded)

This endpoint expects a CreateApplicationRequest.

- `FriendlyName` (string, required) — A named unique identifier for the resource.
- `VoiceUrl` (string, optional) — The URL to request when a phone number receives a call or fax.
- `VoiceMethod` (enum, optional, default: POST) — Whether the request to `VoiceUrl` is a `GET` or a `POST`. Default is `POST`.
  - Allowed values: `GET`, `POST`
- `VoiceFallbackUrl` (string, optional) — The URL SignalWire will request if errors occur when fetching the `VoiceUrl`.
- `VoiceFallbackMethod` (enum, optional, default: POST) — Whether the request to `VoiceFallbackUrl` is a `GET` or a `POST`. Default is `POST`.
  - Allowed values: `GET`, `POST`
- `StatusCallback` (string, optional) — The URL to pass status updates to the Application.
- `StatusCallbackMethod` (enum, optional, default: POST) — Whether the request to the `StatusCallback` URL is a `GET` or a `POST`. Default is `POST`.
  - Allowed values: `GET`, `POST`
- `SmsUrl` (string, optional) — The URL to request when an SMS is received.
- `SmsMethod` (enum, optional, default: POST) — Whether the request to `SmsUrl` is a `GET` or a `POST`. Default is `POST`.
  - Allowed values: `GET`, `POST`
- `SmsFallbackUrl` (string, optional) — The URL SignalWire will request if errors occur when fetching the `SmsUrl`.
- `SmsFallbackMethod` (enum, optional, default: POST) — Whether the request to `SmsFallbackUrl` is a `GET` or a `POST`. Default is `POST`.
  - Allowed values: `GET`, `POST`
- `SmsStatusCallback` (string, optional) — The URL to receive status updates for messages sent via this Application.
- `SmsStatusCallbackMethod` (enum, optional, default: POST) — Whether the request to `SmsStatusCallback` is a `GET` or a `POST`. Default is `POST`.
  - Allowed values: `GET`, `POST`

## Response

### 201

Response containing a newly created application.

- `sid` (string, required) — The unique identifier for the Application.
- `account_sid` (string, required) — The unique identifier for the Account that created this Application.
- `api_version` (string, required) — The version of the SignalWire API.
- `date_created` (string, required) — The date, in RFC 2822 GMT format, this Application was created.
- `date_updated` (string, required) — The date, in RFC 2822 GMT format, this Application was updated.
- `friendly_name` (string, required) — A named unique identifier for the resource.
- `uri` (string, required) — The URI for this Application.
- `voice_url` (string, required, nullable) — The URL to request when a phone number receives a call or fax.
- `voice_method` (string, required, nullable) — Whether the request to `VoiceUrl` is a `GET` or a `POST`. Default is `POST`.
- `voice_fallback_url` (string, required, nullable) — The URL SignalWire will request if errors occur when fetching the `VoiceUrl`.
- `voice_fallback_method` (string, required, nullable) — Whether the request to `VoiceFallbackUrl` is a `GET` or a `POST`. Default is `POST`.
- `status_callback` (string, required, nullable) — The URL to pass status updates to the Application.
- `status_callback_method` (string, required, nullable) — Whether the request to the `StatusCallback` URL is a `GET` or a `POST`. Default is `POST`.
- `voice_caller_id_lookup` (boolean, required, nullable) — Whether or not to look up a caller's ID from the database. Always null.
- `sms_url` (string, required, nullable) — The URL to request when an SMS is received.
- `sms_method` (string, required, nullable) — Whether the request to `SmsUrl` is a `GET` or a `POST`. Default is `POST`.
- `sms_fallback_url` (string, required, nullable) — The URL SignalWire will request if errors occur when fetching the `SmsUrl`.
- `sms_fallback_method` (string, required, nullable) — Whether the request to `SmsFallbackUrl` is a `GET` or a `POST`. Default is `POST`.
- `sms_status_callback` (string, required, nullable) — The URL to receive status updates for messages sent via this Application.
- `sms_status_callback_method` (string, required, nullable) — Whether the request to `SmsStatusCallback` is a `GET` or a `POST`. Default is `POST`.
- `message_status_callback` (string, required, nullable) — The URL to receive status updates for messages sent via this Application.

## Errors

### 400 Bad Request Error

The request was invalid or cannot be processed. Check the error details for more information.

- `code` (integer, required) — Error code.
- `message` (string, required) — Error message.
- `more_info` (string, required) — URL for more information about the error.
- `status` (integer, required) — HTTP status code.

### 401 Unauthorized Error

Authentication failed. Please verify your credentials and try again.

- `code` (integer, required) — Error code.
- `message` (string, required) — Error message.
- `more_info` (string, required) — URL for more information about the error.
- `status` (integer, required) — HTTP status code.

### 422 Unprocessable Entity Error

The request could not be processed due to validation errors. Check the error details for more information.

- `code` (integer, required) — Error code.
- `message` (string, required) — Error message.
- `more_info` (string, required) — URL for more information about the error.
- `status` (integer, required) — HTTP status code.

## Examples

**Request**

```json
{
  "FriendlyName": "My Friendly Name"
}
```

**Response**

```json
{
  "sid": "b3877c40-da60-4998-90ad-b792e98472af",
  "account_sid": "b3877c40-da60-4998-90ad-b792e98472af",
  "api_version": "2010-04-01",
  "date_created": "Sat, 15 Sept 2018 10:00:00 +0000",
  "date_updated": "Sat, 16 Sept 2018 10:00:00 +0000",
  "friendly_name": "My Friendly Name",
  "uri": "/api/laml/2010-04-01/Accounts/b3877c40-da60-4998-90ad-b792e98472af/Applications/b3877c40-da60-4998-90ad-b792e98472af.json",
  "voice_url": "http://example.com",
  "voice_method": "POST",
  "voice_fallback_url": "http://example.com",
  "voice_fallback_method": "POST",
  "status_callback": "http://example.com",
  "status_callback_method": "POST",
  "voice_caller_id_lookup": null,
  "sms_url": "http://example.com",
  "sms_method": "POST",
  "sms_fallback_url": "http://www.example.com/sms-fallback",
  "sms_fallback_method": "POST",
  "sms_status_callback": "http://www.example.com/sms-status-callback",
  "sms_status_callback_method": "POST",
  "message_status_callback": "http://www.example.com/sms-status-callback"
}
```

**SDK Code**

```python
import requests

url = "https://your_space.signalwire.com/api/laml/2010-04-01/Accounts/AccountSid/Applications"

payload = ""
headers = {
    "Content-Type": "application/x-www-form-urlencoded"
}

response = requests.post(url, data=payload, headers=headers, auth=("<project_id>", "<api_token>"))

print(response.json())
```

```javascript
const url = 'https://your_space.signalwire.com/api/laml/2010-04-01/Accounts/AccountSid/Applications';
const credentials = btoa("<project_id>:<api_token>");

const options = {
  method: 'POST',
  headers: {
    Authorization: `Basic ${credentials}`,
    'Content-Type': 'application/x-www-form-urlencoded'
  },
  body: new URLSearchParams('')
};

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"
	"net/http"
	"io"
)

func main() {

	url := "https://your_space.signalwire.com/api/laml/2010-04-01/Accounts/AccountSid/Applications"

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

	req.SetBasicAuth("<project_id>", "<api_token>")
	req.Header.Add("Content-Type", "application/x-www-form-urlencoded")

	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://your_space.signalwire.com/api/laml/2010-04-01/Accounts/AccountSid/Applications")

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

request = Net::HTTP::Post.new(url)
request.basic_auth("<project_id>", "<api_token>")
request["Content-Type"] = 'application/x-www-form-urlencoded'

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://your_space.signalwire.com/api/laml/2010-04-01/Accounts/AccountSid/Applications")
  .basicAuth("<project_id>", "<api_token>")
  .header("Content-Type", "application/x-www-form-urlencoded")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://your_space.signalwire.com/api/laml/2010-04-01/Accounts/AccountSid/Applications', [
  'form_params' => null,
  'headers' => [
    'Content-Type' => 'application/x-www-form-urlencoded',
  ],
    'auth' => ['<project_id>', '<api_token>'],
]);

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

```csharp
using RestSharp;
using RestSharp.Authenticators;

var client = new RestClient("https://your_space.signalwire.com/api/laml/2010-04-01/Accounts/AccountSid/Applications");
client.Authenticator = new HttpBasicAuthenticator("<project_id>", "<api_token>");
var request = new RestRequest(Method.POST);

request.AddHeader("Content-Type", "application/x-www-form-urlencoded");
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let credentials = Data("<project_id>:<api_token>".utf8).base64EncodedString()

let headers = [
  "Authorization": "Basic \(credentials)",
  "Content-Type": "application/x-www-form-urlencoded"
]

let request = NSMutableURLRequest(url: NSURL(string: "https://your_space.signalwire.com/api/laml/2010-04-01/Accounts/AccountSid/Applications")! as URL,
                                        cachePolicy: .useProtocolCachePolicy,
                                    timeoutInterval: 10.0)
request.httpMethod = "POST"
request.allHTTPHeaderFields = headers

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()
```