await client.revisions3D.updateThumbnail(8252999965991682, 4190022127342195, 3243334242324);

res = client.three_d.revisions.update_thumbnail(model_id=1, revision_id=1, file_id=1)

FileMetadata fileMetadata = FileMetadata.newBuilder() 
 .setExternalId("10") 
 .setName("CAMARO_THUMBNAIL_TEST_SDK_JAVA.png") 
 .setSource("sdk-data-generator") 
 .setUploaded(true) 
 .setMimeType("image/png") 
 .putMetadata("type", "sdk-data-generator") 
 .putMetadata("sdk-data-generator", "sdk-data-generator") 
 .build(); 
 byte[] fileByteA = bytes of file; 
 List<FileContainer> list = List.of(FileContainer.newBuilder().setFileMetadata(fileMetadata).setFileBinary(FileBinary.newBuilder() 
          .setBinary(ByteString.copyFrom(fileByteA))).build()); 
List<FileMetadata> uploadFileResult = client.files().upload(list); 

Boolean updated = client 
          .threeD() 
          .models() 
          .revisions() 
          .updateThumbnail(model.getId(), revision.getId(), uploadFileResult.get(0).getId());

curl --request POST \
  --url https://{cluster}.cognitedata.com/api/v1/projects/{project}/3d/models/{modelId}/revisions/{revisionId}/thumbnail \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '{
  "fileId": 123
}'

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://{cluster}.cognitedata.com/api/v1/projects/{project}/3d/models/{modelId}/revisions/{revisionId}/thumbnail",
  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([
    'fileId' => 123
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: application/json"
  ],
]);

$response = curl_exec($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://{cluster}.cognitedata.com/api/v1/projects/{project}/3d/models/{modelId}/revisions/{revisionId}/thumbnail"

	payload := strings.NewReader("{\n  \"fileId\": 123\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(string(body))

}

require 'uri'
require 'net/http'

url = URI("https://{cluster}.cognitedata.com/api/v1/projects/{project}/3d/models/{modelId}/revisions/{revisionId}/thumbnail")

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  \"fileId\": 123\n}"

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

{}

{
  "error": {
    "code": 401,
    "message": "Could not authenticate.",
    "missing": [
      {}
    ],
    "duplicated": [
      {}
    ]
  }
}