curl --request POST \
  --url https://api.smile.io/v1/customer_identities/create_or_update \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "customer_identity": {
    "email": "jane@doe.com",
    "distinct_id": "cust_19238475",
    "first_name": "Jane",
    "last_name": "Doe",
    "properties": {}
  }
}
'

package main

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

func main() {

	url := "https://api.smile.io/v1/customer_identities/create_or_update"

	payload := strings.NewReader("{\n  \"customer_identity\": {\n    \"email\": \"jane@doe.com\",\n    \"distinct_id\": \"cust_19238475\",\n    \"first_name\": \"Jane\",\n    \"last_name\": \"Doe\",\n    \"properties\": {}\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))

}

HttpResponse<String> response = Unirest.post("https://api.smile.io/v1/customer_identities/create_or_update")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"customer_identity\": {\n    \"email\": \"jane@doe.com\",\n    \"distinct_id\": \"cust_19238475\",\n    \"first_name\": \"Jane\",\n    \"last_name\": \"Doe\",\n    \"properties\": {}\n  }\n}")
  .asString();

const url = 'https://api.smile.io/v1/customer_identities/create_or_update';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    customer_identity: {
      email: 'jane@doe.com',
      distinct_id: 'cust_19238475',
      first_name: 'Jane',
      last_name: 'Doe',
      properties: {}
    }
  })
};

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

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.smile.io/v1/customer_identities/create_or_update",
  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([
    'customer_identity' => [
        'email' => 'jane@doe.com',
        'distinct_id' => 'cust_19238475',
        'first_name' => 'Jane',
        'last_name' => 'Doe',
        'properties' => [
                
        ]
    ]
  ]),
  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;
}

$headers=@{}
$headers.Add("Authorization", "Bearer <token>")
$headers.Add("Content-Type", "application/json")
$response = Invoke-WebRequest -Uri 'https://api.smile.io/v1/customer_identities/create_or_update' -Method POST -Headers $headers -ContentType 'application/json' -Body '{
  "customer_identity": {
    "email": "jane@doe.com",
    "distinct_id": "cust_19238475",
    "first_name": "Jane",
    "last_name": "Doe",
    "properties": {}
  }
}'

import requests

url = "https://api.smile.io/v1/customer_identities/create_or_update"

payload = { "customer_identity": {
        "email": "jane@doe.com",
        "distinct_id": "cust_19238475",
        "first_name": "Jane",
        "last_name": "Doe",
        "properties": {}
    } }
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.text)

require 'uri'
require 'net/http'

url = URI("https://api.smile.io/v1/customer_identities/create_or_update")

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  \"customer_identity\": {\n    \"email\": \"jane@doe.com\",\n    \"distinct_id\": \"cust_19238475\",\n    \"first_name\": \"Jane\",\n    \"last_name\": \"Doe\",\n    \"properties\": {}\n  }\n}"

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

{
  "customer_identity": {
    "id": 863291377,
    "first_name": "Jane",
    "last_name": "Doe",
    "email": "jane@doe.com",
    "distinct_id": "cust_19238475",
    "properties": {},
    "customer_id": 123
  }
}

{
  "customer_identity": {
    "id": 863291377,
    "first_name": "Jane",
    "last_name": "Doe",
    "email": "jane@doe.com",
    "distinct_id": "cust_19238475",
    "properties": {},
    "customer_id": 123
  }
}