# POST /api/notifications/listen-sessions/{id}/sample

Stages the event catalog's sample for one event type into a live session's buffer.

The destination-bound sample send cannot reach a session: it bypasses dispatch entirely. This
is the session-targeted equivalent, built from the same sample factory and the same envelope
leg, so a receiver validated against the published schema is validated against this too.



Sandbox-only. A caller acting in the live world is refused, as is one carrying no evidence of
which world it is acting in: a sample is a synthetic event that never happened, and staging
one into a production feed puts an invented occurrence in front of a receiver processing real
traffic.

**Operation ID:** `notificationsStageSample`

## Authorization

Requires: Notifications.ListenSessions.Listen, Notifications.Destinations.Test, merchant scope.

Requires API key scope: `webhooks`

Required permissions:
- `Notifications.ListenSessions.Listen`
- `Notifications.Destinations.Test`

## Parameters

| Name | In | Required | Type | Description |
| --- | --- | --- | --- | --- |
| id | path | yes | string(uuid) |  |
| suppressNulls | query | no | boolean | If true, omit properties with null values. |

## Request Body

**Content type:** `application/json`

Schema: [`StageSampleEventInput`](https://devportal.demo.winkpg.io/docs/api/models/StageSampleEventInput.md)

Properties:
- `eventType` (string) required: Canonical event type to build the sample for. (nullable, max length 256)

**Content type:** `text/json`

Schema: [`StageSampleEventInput`](https://devportal.demo.winkpg.io/docs/api/models/StageSampleEventInput.md)

Properties:
- `eventType` (string) required: Canonical event type to build the sample for. (nullable, max length 256)

**Content type:** `application/*+json`

Schema: [`StageSampleEventInput`](https://devportal.demo.winkpg.io/docs/api/models/StageSampleEventInput.md)

Properties:
- `eventType` (string) required: Canonical event type to build the sample for. (nullable, max length 256)

## Responses

### 200

The sample was staged and will arrive on the next poll.

**Content type:** `application/json`

Schema: [`ListenSessionEventDto`](https://devportal.demo.winkpg.io/docs/api/models/ListenSessionEventDto.md)

Properties:
- `id` (string(uuid)): The staged-event id. The client's dedupe key across the cursor's overlap window.
- `stagedAtUtc` (string(date-time)): When the event was staged. The first half of the cursor.
- `eventId` (string): The platform event id, forwarded as `X-WinkPG-Event-Id`. (nullable)
- `eventType` (string): Canonical event type. (nullable)
- `deliveryId` (string(uuid)): The per-staged-event delivery id, forwarded as `X-WinkPG-Delivery-Id`.
- `isSample` (boolean): Whether this event was staged by a sample request rather than a live occurrence. When true, the  forward to the local target carries `X-WinkPG-Sample: true`, the same marker a sample sent  to a saved endpoint carries. The body is identical either way.
- `payload` (string): The webhook body, verbatim. Forwarded to the local target byte for byte: re-serializing it  client-side would change the bytes the signature covers and break verification. (nullable)

### 403

The event type is unregistered, undeliverable, or outside the caller's scope; or the caller is
not acting in the test world, which sample events require.

### 404

No such session for this caller, or it is no longer active.

**Content type:** `application/json`

Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md)

Properties:
- `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md))

_Example: Resource not found_

The id in the path names no record the caller can see. Most resources answer with a null error.code and a message naming the resource type and the id; a resource that publishes a not-found code in the catalog above carries it in error.code instead, so check for one before matching on the message.

```json
{
  "error": {
    "code": "null",
    "message": "There is no entity Transaction with id = 7d1f3a52-0c4e-4b8a-9e21-5a6b7c8d9e00!",
    "details": "null",
    "data": {
      "correlationId": "0123456789abcdef0123456789abcdef"
    },
    "validationErrors": "null"
  }
}
```

### default

The request failed. The body carries the standard error envelope: a machine-readable `error.code`, a human-readable `error.message`, and `error.validationErrors` when the failure was a validation rejection. The [error reference](https://devportal.demo.winkpg.io/docs/errors.md) lists the values `error.code` can take.

**Content type:** `application/json`

Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md)

Properties:
- `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md))

_Example: Business rule refused the request_

The request was understood and rejected by a platform rule. This is the shape that carries a code from the catalog above, so branch on error.code rather than on the message text. The HTTP status is the one listed against the code.

```json
{
  "error": {
    "code": "Transactions:OperationNotAllowed",
    "message": "The operation 'Void' is not allowed on a Sale transaction with result 'Approved' and settlement state 'Settled'.",
    "details": "null",
    "data": {
      "correlationId": "0123456789abcdef0123456789abcdef"
    },
    "validationErrors": "null"
  }
}
```

_Example: Request failed validation_

One or more fields were rejected before any rule ran. error.code is null on the envelope and the causes are in validationErrors, one entry per failure. An entry carries code when the validator declared a publishable one, and memberPaths when the full path says more than members does (an element inside a collection, for example). Both keys are omitted when they would add nothing.

```json
{
  "error": {
    "code": "null",
    "message": "Your request is not valid!",
    "details": "The following errors were detected during validation.",
    "data": {
      "correlationId": "0123456789abcdef0123456789abcdef"
    },
    "validationErrors": [
      {
        "message": "'Amount' must be greater than 0.",
        "members": [
          "amount"
        ]
      },
      {
        "message": "The card has expired.",
        "members": [
          "expirationDate"
        ],
        "code": "CardData:CardExpired"
      },
      {
        "message": "'Value' must not be empty.",
        "members": [
          "value"
        ],
        "memberPaths": [
          "customFields[2].value"
        ]
      }
    ]
  }
}
```

_Example: Unexpected server fault_

Something failed that no rule anticipated. There is no code to branch on and the message is deliberately generic: the diagnostic detail stays in the platform's logs rather than going to the caller. Quote error.data.correlationId (the same value as the X-Correlation-Id response header) when you contact support: it's what finds the failure in those logs. Retrying an unsafe operation after this risks a duplicate, so reconcile before you retry.

```json
{
  "error": {
    "code": "null",
    "message": "An internal error occurred during your request!",
    "details": "null",
    "data": {
      "correlationId": "0123456789abcdef0123456789abcdef"
    },
    "validationErrors": "null"
  }
}
```

### 429

The request was refused because a rate limit was exceeded, or because something a later retry can clear stopped it. A rate limit refusal carries an `application/problem+json` body: wait at least the interval `Retry-After` names before retrying, then back off. Limits are tuned per deployment, so read the allowance from the response headers rather than assuming a fixed ceiling. Any other refusal carries the standard error envelope as `application/json`, and its `error.code` names the cause.

**Content type:** `application/problem+json`

Schema: [`RateLimitProblemDetails`](https://devportal.demo.winkpg.io/docs/api/models/RateLimitProblemDetails.md)

Properties:
- `type` (string) required: The problem type identifier. Always the same value: the failure is the status code itself,  so there is no sub-type for a caller to branch on. (nullable)
- `title` (string) required: A short, human-readable summary of the problem type. (nullable)
- `status` (integer(int32)) required: The HTTP status code, repeated in the body as the problem-details format defines.
- `detail` (string) required: A human-readable explanation of this occurrence of the problem. (nullable)
- `retryAfterSeconds` (integer(int32)) required: How long to wait before retrying, in whole seconds, carrying the same figure as the  `Retry-After` header. Always at least one: a value of zero would invite an immediate  retry that is certain to be rejected again.

**Content type:** `application/json`

Schema: [`RemoteServiceErrorResponse`](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorResponse.md)

Properties:
- `error` ([RemoteServiceErrorInfo](https://devportal.demo.winkpg.io/docs/api/models/RemoteServiceErrorInfo.md))

## Example request

Every block below sends the same request. Replace {{BASE_URL}} with the address of the API you are calling and {{API_KEY}} with your own key.

The request body is a StageSampleEventInput. See the Request body section below for its fields.

### cURL

```bash
curl -X POST "{{BASE_URL}}/api/notifications/listen-sessions/{id}/sample" \
  -H "api-key: {{API_KEY}}" \
  -H "Content-Type: application/json" \
  -d '{
  "eventType": ""
}'
```

### PowerShell

```powershell
$headers = @{
    'api-key' = '{{API_KEY}}'
}

$body = @'
{
  "eventType": ""
}
'@

$response = Invoke-RestMethod -Method POST -Uri '{{BASE_URL}}/api/notifications/listen-sessions/{id}/sample' `
    -Headers $headers -ContentType 'application/json' -Body $body
```

### TypeScript (SDK)

```bash
npm install @winkpg/winkpg-api
```

```typescript
import { Configuration, NotificationsApi } from '@winkpg/winkpg-api';

const api = new NotificationsApi(new Configuration({
  basePath: '{{BASE_URL}}',
  apiKey: '{{API_KEY}}',
}));

const { data } = await api.notificationsStageSample("3fa85f64-5717-4562-b3fc-2c963f66afa6", {
  "eventType": ""
});
```

### TypeScript (raw HTTP)

```typescript
const response = await fetch('{{BASE_URL}}/api/notifications/listen-sessions/{id}/sample', {
  method: 'POST',
  headers: {
    "api-key": "{{API_KEY}}",
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "eventType": ""
  }),
});

const data = await response.json();
```

### C# (SDK)

```bash
dotnet add package WinkPg.Api.Client
```

```csharp
using WinkPg.Api.Client.Api;
using WinkPg.Api.Client.Client;
using System.Text.Json;

var config = new Configuration { BasePath = "{{BASE_URL}}" };
config.AddApiKey("api-key", "{{API_KEY}}");

var api = new NotificationsApi(config);
var body = JsonSerializer.Deserialize<StageSampleEventInput>("""
    {
      "eventType": ""
    }
    """);

var result = await api.NotificationsStageSampleAsync(Guid.Parse("3fa85f64-5717-4562-b3fc-2c963f66afa6"), body);
```

### C# (raw HTTP)

```csharp
using System.Text;

using var http = new HttpClient { BaseAddress = new Uri("{{BASE_URL}}") };

var request = new HttpRequestMessage(new HttpMethod("POST"), "/api/notifications/listen-sessions/{id}/sample");
request.Headers.Add("api-key", "{{API_KEY}}");

request.Content = new StringContent("""
    {
      "eventType": ""
    }
    """, Encoding.UTF8, "application/json");

var response = await http.SendAsync(request);
response.EnsureSuccessStatusCode();
var json = await response.Content.ReadAsStringAsync();
```

### Python (SDK)

```bash
pip install winkpg-api
```

```python
import winkpg_api

configuration = winkpg_api.Configuration(host="{{BASE_URL}}")
configuration.api_key["ApiKey"] = "{{API_KEY}}"

with winkpg_api.ApiClient(configuration) as client:
    api = winkpg_api.NotificationsApi(client)
    body = winkpg_api.StageSampleEventInput.from_dict({
      "eventType": ""
    })
    result = api.notifications_stage_sample("3fa85f64-5717-4562-b3fc-2c963f66afa6", body)
```

### Python (raw HTTP)

```bash
pip install requests
```

```python
import requests

headers = {
    "api-key": "{{API_KEY}}",
    "Content-Type": "application/json",
}

body = {
  "eventType": ""
}

response = requests.request(
    "POST",
    "{{BASE_URL}}/api/notifications/listen-sessions/{id}/sample",
    headers=headers,
    json=body,
)
response.raise_for_status()
data = response.json()
```

## See also

- [All documentation](https://devportal.demo.winkpg.io/llms.txt): the machine-readable index of every public page on this site.