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> For a complete documentation index, see https://docs.datafortennis.com/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.datafortennis.com/_mcp/server.

# Preview a private export

POST https://api.datafortennis.com/v1/exports/preview
Content-Type: application/json

Bounded estimate from immutable prepared counts. Encoded bytes are measured by generation, not guessed. Defaults: 250000 rows and 256MiB across the entire job; larger operator limits require explicit configuration.

Reference: https://docs.datafortennis.com/api-reference/preview-export

## Authentication

- `Authorization` header (bearer token, required) — Private development credential: keyId.secret; rotate/revoke through the offline operations CLI.

## Request

### Body (application/json)

This endpoint expects an object.

- `family` (enum, required)
  - Allowed values: `points`, `stats`
- `format` (enum, required)
  - Allowed values: `ndjson`, `parquet`
- `filters` (V1ExportsPreviewPostRequestBodyContentApplicationJsonSchemaFilters, required)
- `release` (string, optional)
- `max_rows` (integer, optional)
- `max_bytes` (integer, optional)

## Response

### 200

Private export control result.

- `data` (PreviewExportResponseData, required)
- `meta` (PreviewExportResponseMeta, required, nullable)
- `page` (PreviewExportResponsePage, required, nullable)
- `error` (PreviewExportResponseError, required, nullable)

## Errors

### 400 Bad Request Error

Invalid input

- `data` (ErrorData, required, nullable)
- `meta` (ErrorMeta, required, nullable)
- `page` (ErrorPage, required, nullable)
- `error` (ErrorError, required)

### 401 Unauthorized Error

Invalid credential

- `data` (ErrorData, required, nullable)
- `meta` (ErrorMeta, required, nullable)
- `page` (ErrorPage, required, nullable)
- `error` (ErrorError, required)

### 403 Forbidden Error

Scope denied

- `data` (ErrorData, required, nullable)
- `meta` (ErrorMeta, required, nullable)
- `page` (ErrorPage, required, nullable)
- `error` (ErrorError, required)

### 404 Not Found Error

Unknown resource

- `data` (ErrorData, required, nullable)
- `meta` (ErrorMeta, required, nullable)
- `page` (ErrorPage, required, nullable)
- `error` (ErrorError, required)

### 409 Conflict Error

Idempotency key conflicts with its bound request

- `data` (ErrorData, required, nullable)
- `meta` (ErrorMeta, required, nullable)
- `page` (ErrorPage, required, nullable)
- `error` (ErrorError, required)

### 410 Gone Error

Cursor or idempotency replay window expired

- `data` (ErrorData, required, nullable)
- `meta` (ErrorMeta, required, nullable)
- `page` (ErrorPage, required, nullable)
- `error` (ErrorError, required)

### 413 Content Too Large Error

Response budget exceeded

- `data` (ErrorData, required, nullable)
- `meta` (ErrorMeta, required, nullable)
- `page` (ErrorPage, required, nullable)
- `error` (ErrorError, required)

### 414 URI Too Long Error

URI too long

- `data` (ErrorData, required, nullable)
- `meta` (ErrorMeta, required, nullable)
- `page` (ErrorPage, required, nullable)
- `error` (ErrorError, required)

### 429 Too Many Requests Error

Request budget exceeded

- `data` (ErrorData, required, nullable)
- `meta` (ErrorMeta, required, nullable)
- `page` (ErrorPage, required, nullable)
- `error` (ErrorError, required)

### 503 Service Unavailable Error

Temporarily unavailable

- `data` (ErrorData, required, nullable)
- `meta` (ErrorMeta, required, nullable)
- `page` (ErrorPage, required, nullable)
- `error` (ErrorError, required)

## Types

### V1ExportsPreviewPostRequestBodyContentApplicationJsonSchemaFilters

- `season` (integer, optional)
- `discipline` (enum, optional)
  - Allowed values: `singles`, `doubles`
- `match_ids` (list of string, optional)

### PreviewExportResponseData

- `release_id` (string, required)
- `epoch` (string, required)
- `family` (string, required)
- `format` (string, required)
- `estimated_rows` (string, required)
- `census_matches` (string, required)
- `with_rows` (string, required)
- `unknown_pbp_assessment` (string, required)
- `walkovers` (string, required)
- `row_limit` (string, required)
- `byte_limit` (string, required)
- `confidence` (enum, required)
  - Allowed values: `exact_prepared_counts`
- `estimated_bytes` (string, required, nullable)
- `fits_rows` (boolean, required)

### PreviewExportResponseMeta

- `release_id` (string, required)
- `epoch` (string, required)
- `schema_version` (string, required)
- `quality_version` (string, required)
- `availability` (list of Coverage, required, nullable)
- `calendar` (PreviewExportResponseMetaCalendar, optional)
- `capability` (PreviewExportResponseMetaCapability, optional)

### PreviewExportResponsePage

- `limit` (integer, required)
- `next_cursor` (string, required, nullable)

### PreviewExportResponseError

### ErrorData

### ErrorMeta

### ErrorPage

### ErrorError

- `code` (string, required)
- `message` (string, required)
- `request_id` (string, required)

### Coverage

- `family` (string, required)
- `discipline` (string, required)
- `census` (string, required)
- `available` (string, required)
- `missing` (string, required)
- `unknown` (string, required)
- `not_applicable` (string, required)
- `known_applicable` (string, required)
- `missing_assessment` (string, required)
- `partial` (string, required)
- `usable_rows` (string, required)
- `derived_rows` (string, required)
- `definition` (enum, optional)
  - Allowed values: `enrichment/1`
- `grain` (enum, optional)
  - Allowed values: `point`, `side_stroke_summary`, `clock_evidence`
- `point_numerator` (string, optional, nullable)
- `point_denominator` (string, optional, nullable)
- `density` (string, optional, nullable)
- `conflict_rows` (string, optional)
- `category` (string, optional)

### PreviewExportResponseMetaCalendar

- `precision` (enum, required)
  - Allowed values: `day`
- `unknown_dates_excluded` (boolean, required)
- `complete_calendar` (boolean, required)

### PreviewExportResponseMetaCapability

- `family` (enum, required)
  - Allowed values: `rally`, `strokes`, `time_evidence`
- `status` (enum, required)
  - Allowed values: `supported`, `not_projected_in_release`
- `definition` (enum, required)
  - Allowed values: `enrichment/1`

## Examples

**Request**

```json
{
  "family": "points",
  "format": "ndjson"
}
```

**Response**

```json
{
  "data": {
    "release_id": "string",
    "epoch": "string",
    "family": "string",
    "format": "string",
    "estimated_rows": "string",
    "census_matches": "string",
    "with_rows": "string",
    "unknown_pbp_assessment": "string",
    "walkovers": "string",
    "row_limit": "string",
    "byte_limit": "string",
    "confidence": "exact_prepared_counts",
    "estimated_bytes": null,
    "fits_rows": true
  },
  "meta": {
    "release_id": "string",
    "epoch": "string",
    "schema_version": "string",
    "quality_version": "string",
    "availability": [
      {
        "family": "string",
        "discipline": "string",
        "census": "string",
        "available": "string",
        "missing": "string",
        "unknown": "string",
        "not_applicable": "string",
        "known_applicable": "string",
        "missing_assessment": "string",
        "partial": "string",
        "usable_rows": "string",
        "derived_rows": "string",
        "definition": "enrichment/1",
        "grain": "point",
        "point_numerator": "string",
        "point_denominator": "string",
        "density": "string",
        "conflict_rows": "string",
        "category": "string"
      }
    ],
    "calendar": {
      "precision": "day",
      "unknown_dates_excluded": true,
      "complete_calendar": true
    },
    "capability": {
      "family": "rally",
      "status": "supported",
      "definition": "enrichment/1"
    }
  },
  "page": {
    "limit": 1,
    "next_cursor": "string"
  },
  "error": null
}
```

**SDK Code**

```python
import requests

url = "https://api.datafortennis.com/v1/exports/preview"

payload = {
    "family": "points",
    "format": "ndjson"
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.json())
```

```javascript
const url = 'https://api.datafortennis.com/v1/exports/preview';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: '{"family":"points","format":"ndjson"}'
};

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://api.datafortennis.com/v1/exports/preview"

	payload := strings.NewReader("{\n  \"family\": \"points\",\n  \"format\": \"ndjson\"\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://api.datafortennis.com/v1/exports/preview")

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  \"family\": \"points\",\n  \"format\": \"ndjson\"\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://api.datafortennis.com/v1/exports/preview")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"family\": \"points\",\n  \"format\": \"ndjson\"\n}")
  .asString();
```

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

$client = new \GuzzleHttp\Client();

$response = $client->request('POST', 'https://api.datafortennis.com/v1/exports/preview', [
  'body' => '{
  "family": "points",
  "format": "ndjson"
}',
  'headers' => [
    'Authorization' => 'Bearer <token>',
    'Content-Type' => 'application/json',
  ],
]);

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

```csharp
using RestSharp;

var client = new RestClient("https://api.datafortennis.com/v1/exports/preview");
var request = new RestRequest(Method.POST);
request.AddHeader("Authorization", "Bearer <token>");
request.AddHeader("Content-Type", "application/json");
request.AddParameter("application/json", "{\n  \"family\": \"points\",\n  \"format\": \"ndjson\"\n}", ParameterType.RequestBody);
IRestResponse response = client.Execute(request);
```

```swift
import Foundation

let headers = [
  "Authorization": "Bearer <token>",
  "Content-Type": "application/json"
]
let parameters = [
  "family": "points",
  "format": "ndjson"
] as [String : Any]

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

let request = NSMutableURLRequest(url: NSURL(string: "https://api.datafortennis.com/v1/exports/preview")! 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()
```