curl --request POST \
  --url https://sandbox.api.fin.com/v1/customers/business/attach \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "customer_id": "2d0a9df3-e1e5-4955-9759-ce0522e0ddc9",
  "ownership_structure": [
    {
      "type": "SHAREHOLDER_REGISTRY",
      "files": [
        {
          "uri": "/AbAcQ4hn_0652746727639.pdf"
        }
      ]
    }
  ],
  "company_details": [
    {
      "type": "CERT_OF_INCORPORATION",
      "files": [
        {
          "uri": "/AbAcQ4hn_0652746727640.pdf"
        }
      ]
    }
  ],
  "legal_presence": [
    {
      "type": "PROOF_OF_ADDRESS",
      "files": [
        {
          "uri": "/AbAcQ4hn_0652746727641.pdf"
        }
      ]
    }
  ],
  "tos_policies_value": "e9414388-fbdf-4407-b5c2-bc39eae3645b"
}
'

const url = 'https://sandbox.api.fin.com/v1/customers/business/attach';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    customer_id: '2d0a9df3-e1e5-4955-9759-ce0522e0ddc9',
    ownership_structure: [{type: 'SHAREHOLDER_REGISTRY', files: [{uri: '/AbAcQ4hn_0652746727639.pdf'}]}],
    company_details: [{type: 'CERT_OF_INCORPORATION', files: [{uri: '/AbAcQ4hn_0652746727640.pdf'}]}],
    legal_presence: [{type: 'PROOF_OF_ADDRESS', files: [{uri: '/AbAcQ4hn_0652746727641.pdf'}]}],
    tos_policies_value: 'e9414388-fbdf-4407-b5c2-bc39eae3645b'
  })
};

fetch(url, options)
  .then(res => res.json())
  .then(json => console.log(json))
  .catch(err => console.error(err));

HttpResponse<String> response = Unirest.post("https://sandbox.api.fin.com/v1/customers/business/attach")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"customer_id\": \"2d0a9df3-e1e5-4955-9759-ce0522e0ddc9\",\n  \"ownership_structure\": [\n    {\n      \"type\": \"SHAREHOLDER_REGISTRY\",\n      \"files\": [\n        {\n          \"uri\": \"/AbAcQ4hn_0652746727639.pdf\"\n        }\n      ]\n    }\n  ],\n  \"company_details\": [\n    {\n      \"type\": \"CERT_OF_INCORPORATION\",\n      \"files\": [\n        {\n          \"uri\": \"/AbAcQ4hn_0652746727640.pdf\"\n        }\n      ]\n    }\n  ],\n  \"legal_presence\": [\n    {\n      \"type\": \"PROOF_OF_ADDRESS\",\n      \"files\": [\n        {\n          \"uri\": \"/AbAcQ4hn_0652746727641.pdf\"\n        }\n      ]\n    }\n  ],\n  \"tos_policies_value\": \"e9414388-fbdf-4407-b5c2-bc39eae3645b\"\n}")
  .asString();

import requests

url = "https://sandbox.api.fin.com/v1/customers/business/attach"

payload = {
    "customer_id": "2d0a9df3-e1e5-4955-9759-ce0522e0ddc9",
    "ownership_structure": [
        {
            "type": "SHAREHOLDER_REGISTRY",
            "files": [{ "uri": "/AbAcQ4hn_0652746727639.pdf" }]
        }
    ],
    "company_details": [
        {
            "type": "CERT_OF_INCORPORATION",
            "files": [{ "uri": "/AbAcQ4hn_0652746727640.pdf" }]
        }
    ],
    "legal_presence": [
        {
            "type": "PROOF_OF_ADDRESS",
            "files": [{ "uri": "/AbAcQ4hn_0652746727641.pdf" }]
        }
    ],
    "tos_policies_value": "e9414388-fbdf-4407-b5c2-bc39eae3645b"
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.text)

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://sandbox.api.fin.com/v1/customers/business/attach"

	payload := strings.NewReader("{\n  \"customer_id\": \"2d0a9df3-e1e5-4955-9759-ce0522e0ddc9\",\n  \"ownership_structure\": [\n    {\n      \"type\": \"SHAREHOLDER_REGISTRY\",\n      \"files\": [\n        {\n          \"uri\": \"/AbAcQ4hn_0652746727639.pdf\"\n        }\n      ]\n    }\n  ],\n  \"company_details\": [\n    {\n      \"type\": \"CERT_OF_INCORPORATION\",\n      \"files\": [\n        {\n          \"uri\": \"/AbAcQ4hn_0652746727640.pdf\"\n        }\n      ]\n    }\n  ],\n  \"legal_presence\": [\n    {\n      \"type\": \"PROOF_OF_ADDRESS\",\n      \"files\": [\n        {\n          \"uri\": \"/AbAcQ4hn_0652746727641.pdf\"\n        }\n      ]\n    }\n  ],\n  \"tos_policies_value\": \"e9414388-fbdf-4407-b5c2-bc39eae3645b\"\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))

}

{
  "data": {}
}

{
  "message": "Authentication failed"
}

{
  "message": "<string>",
  "errors": [
    {}
  ]
}