curl --request POST \
  --url https://api.sandbox.immutable.com/v1/chains/{chain_name}/crafting/sign \
  --header 'Content-Type: application/json' \
  --header 'x-immutable-api-key: <api-key>' \
  --data '
{
  "multi_caller": {
    "address": "0xe9b00a87700f660e46b6f5deaa1232836bcc07d3",
    "name": "Multicaller",
    "version": "1"
  },
  "reference_id": "67f7d464b8f04f6a9a3b8d3cb4a21af0",
  "calls": [
    {
      "target_address": "0xe9b00a87700f660e46b6f5deaa1232836bcc07d3",
      "function_signature": "mint(address,uint256)",
      "function_args": [
        "0x8a90cab2b38dba80c64b7734e58ee1db38b8992e",
        "1"
      ]
    }
  ],
  "expires_at": "2022-08-16T17:43:26.991388Z"
}
'

import requests

url = "https://api.sandbox.immutable.com/v1/chains/{chain_name}/crafting/sign"

payload = {
    "multi_caller": {
        "address": "0xe9b00a87700f660e46b6f5deaa1232836bcc07d3",
        "name": "Multicaller",
        "version": "1"
    },
    "reference_id": "67f7d464b8f04f6a9a3b8d3cb4a21af0",
    "calls": [
        {
            "target_address": "0xe9b00a87700f660e46b6f5deaa1232836bcc07d3",
            "function_signature": "mint(address,uint256)",
            "function_args": ["0x8a90cab2b38dba80c64b7734e58ee1db38b8992e", "1"]
        }
    ],
    "expires_at": "2022-08-16T17:43:26.991388Z"
}
headers = {
    "x-immutable-api-key": "<api-key>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {'x-immutable-api-key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    multi_caller: {
      address: '0xe9b00a87700f660e46b6f5deaa1232836bcc07d3',
      name: 'Multicaller',
      version: '1'
    },
    reference_id: '67f7d464b8f04f6a9a3b8d3cb4a21af0',
    calls: [
      {
        target_address: '0xe9b00a87700f660e46b6f5deaa1232836bcc07d3',
        function_signature: 'mint(address,uint256)',
        function_args: ['0x8a90cab2b38dba80c64b7734e58ee1db38b8992e', '1']
      }
    ],
    expires_at: '2022-08-16T17:43:26.991388Z'
  })
};

fetch('https://api.sandbox.immutable.com/v1/chains/{chain_name}/crafting/sign', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://api.sandbox.immutable.com/v1/chains/{chain_name}/crafting/sign",
  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([
    'multi_caller' => [
        'address' => '0xe9b00a87700f660e46b6f5deaa1232836bcc07d3',
        'name' => 'Multicaller',
        'version' => '1'
    ],
    'reference_id' => '67f7d464b8f04f6a9a3b8d3cb4a21af0',
    'calls' => [
        [
                'target_address' => '0xe9b00a87700f660e46b6f5deaa1232836bcc07d3',
                'function_signature' => 'mint(address,uint256)',
                'function_args' => [
                                '0x8a90cab2b38dba80c64b7734e58ee1db38b8992e',
                                '1'
                ]
        ]
    ],
    'expires_at' => '2022-08-16T17:43:26.991388Z'
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "x-immutable-api-key: <api-key>"
  ],
]);

$response = curl_exec($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://api.sandbox.immutable.com/v1/chains/{chain_name}/crafting/sign"

	payload := strings.NewReader("{\n  \"multi_caller\": {\n    \"address\": \"0xe9b00a87700f660e46b6f5deaa1232836bcc07d3\",\n    \"name\": \"Multicaller\",\n    \"version\": \"1\"\n  },\n  \"reference_id\": \"67f7d464b8f04f6a9a3b8d3cb4a21af0\",\n  \"calls\": [\n    {\n      \"target_address\": \"0xe9b00a87700f660e46b6f5deaa1232836bcc07d3\",\n      \"function_signature\": \"mint(address,uint256)\",\n      \"function_args\": [\n        \"0x8a90cab2b38dba80c64b7734e58ee1db38b8992e\",\n        \"1\"\n      ]\n    }\n  ],\n  \"expires_at\": \"2022-08-16T17:43:26.991388Z\"\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("x-immutable-api-key", "<api-key>")
	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.sandbox.immutable.com/v1/chains/{chain_name}/crafting/sign")
  .header("x-immutable-api-key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"multi_caller\": {\n    \"address\": \"0xe9b00a87700f660e46b6f5deaa1232836bcc07d3\",\n    \"name\": \"Multicaller\",\n    \"version\": \"1\"\n  },\n  \"reference_id\": \"67f7d464b8f04f6a9a3b8d3cb4a21af0\",\n  \"calls\": [\n    {\n      \"target_address\": \"0xe9b00a87700f660e46b6f5deaa1232836bcc07d3\",\n      \"function_signature\": \"mint(address,uint256)\",\n      \"function_args\": [\n        \"0x8a90cab2b38dba80c64b7734e58ee1db38b8992e\",\n        \"1\"\n      ]\n    }\n  ],\n  \"expires_at\": \"2022-08-16T17:43:26.991388Z\"\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.sandbox.immutable.com/v1/chains/{chain_name}/crafting/sign")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["x-immutable-api-key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"multi_caller\": {\n    \"address\": \"0xe9b00a87700f660e46b6f5deaa1232836bcc07d3\",\n    \"name\": \"Multicaller\",\n    \"version\": \"1\"\n  },\n  \"reference_id\": \"67f7d464b8f04f6a9a3b8d3cb4a21af0\",\n  \"calls\": [\n    {\n      \"target_address\": \"0xe9b00a87700f660e46b6f5deaa1232836bcc07d3\",\n      \"function_signature\": \"mint(address,uint256)\",\n      \"function_args\": [\n        \"0x8a90cab2b38dba80c64b7734e58ee1db38b8992e\",\n        \"1\"\n      ]\n    }\n  ],\n  \"expires_at\": \"2022-08-16T17:43:26.991388Z\"\n}"

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

{
  "signer_address": "0xe9b00a87700f660e46b6f5deaa1232836bcc07d3",
  "signature": "0x8a90cab2b38dba80c64b7734e58ee1db38b8992e"
}

{
  "message": "all fields must be provided",
  "link": "https://docs.x.immutable.com/reference/#/",
  "trace_id": "e47634b79a5cd6894ddc9639ec4aad26",
  "code": "VALIDATION_ERROR",
  "details": {}
}

{
  "message": "all fields must be provided",
  "link": "https://docs.x.immutable.com/reference/#/",
  "trace_id": "e47634b79a5cd6894ddc9639ec4aad26",
  "code": "UNAUTHORISED_REQUEST",
  "details": {}
}

{
  "message": "all fields must be provided",
  "link": "https://docs.x.immutable.com/reference/#/",
  "trace_id": "e47634b79a5cd6894ddc9639ec4aad26",
  "code": "AUTHENTICATION_ERROR",
  "details": {}
}

{
  "message": "all fields must be provided",
  "link": "https://docs.x.immutable.com/reference/#/",
  "trace_id": "e47634b79a5cd6894ddc9639ec4aad26",
  "code": "RESOURCE_NOT_FOUND",
  "details": {}
}

{
  "message": "all fields must be provided",
  "link": "https://docs.x.immutable.com/reference/#/",
  "trace_id": "e47634b79a5cd6894ddc9639ec4aad26",
  "code": "INTERNAL_SERVER_ERROR",
  "details": {}
}