const assetMappingsToCreate = [
 {
   nodeId: 8252999965991682,
   assetId: 4354399876978078
 },
 {
   nodeId: 9034285498543958,
   assetId: 1042345809544395
 }
];
const mappings3D = await client.assetMappings3D.create(
 25432542356436,
 33485743958747,
 assetMappingsToCreate
);

from cognite.client.data_classes import ThreeDAssetMappingWrite
my_mapping = ThreeDAssetMappingWrite(node_id=1, asset_id=1)
res = client.three_d.asset_mappings.create(model_id=1, revision_id=1, asset_mapping=my_mapping)

 List<ThreeDAssetMapping> items = List.of(ThreeDAssetMapping.newBuilder() 
          .setAssetId(1L) 
          .setNodeId(1L) 
          .build()); 

List<ThreeDAssetMapping> listCreated = client.threeD() 
          .models() 
          .revisions() 
          .assetMappings() 
          .create(model.getId(), revision.getId(), items); 

curl --request POST \
  --url https://{cluster}.cognitedata.com/api/v1/projects/{project}/3d/models/{modelId}/revisions/{revisionId}/mappings \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "items": [
    {
      "nodeId": 1003,
      "assetId": 3001
    }
  ]
}
'

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://{cluster}.cognitedata.com/api/v1/projects/{project}/3d/models/{modelId}/revisions/{revisionId}/mappings",
  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([
    'items' => [
        [
                'nodeId' => 1003,
                'assetId' => 3001
        ]
    ]
  ]),
  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}/mappings"

	payload := strings.NewReader("{\n  \"items\": [\n    {\n      \"nodeId\": 1003,\n      \"assetId\": 3001\n    }\n  ]\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}/mappings")

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  \"items\": [\n    {\n      \"nodeId\": 1003,\n      \"assetId\": 3001\n    }\n  ]\n}"

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

{
  "items": [
    {
      "nodeId": 1003,
      "assetId": 3001,
      "assetInstanceId": {
        "space": "<string>",
        "externalId": "<string>"
      },
      "treeIndex": 3,
      "subtreeSize": 4
    }
  ]
}

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