Coinbase button creation and callback

Question

Im trying to create a button and assign a callback URL with coinbase.

I'm getting some CAPTCHA data returned when trying to post to coinbase API.

I think my webhost is getting blocked by CloudFlare, disabling my code.

Here's what I have:

<a class="coinbase-button" data-code="<?php

$data = array(
  "button" => array(
    "name" => "Ticket",
    "price_string" => "0.01",
    "price_currency_iso" => "BTC",
    "custom" => $OrderNext . "- " . $ticket,
    "callback_url" => "https://x.com/callback.php",
    "description" => "Ticket - " . $ticket ,
    "type" => "buy_now",
    "style" => "buy_now_large"
  )
);                                                                    

$json_data = json_encode($data);                                                                                   

$ch = curl_init("https://coinbase.com/api/v1/buttons?api_key=xxxxxxxxxxxxxxxxxxxxxx");

curl_setopt($ch, CURLOPT_POST, 1);                                                                  
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST"); 
curl_setopt($ch, CURLOPT_POSTFIELDS, $json_data);                                                                  
curl_setopt($ch, CURLOPT_HEADER, 0);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);                                                                      
curl_setopt($ch, CURLOPT_HTTPHEADER, array(                                                                          
  'Content-Type: application/json',                                                                                
  'Content-Length: ' . strlen($json_data))                                                                       
);                                                                                                                   

if( ! $output = curl_exec($ch))
  {
        trigger_error(curl_error($ch));
    } 

$result = json_decode($output);

$output returns a CAPTCHA page.

$result is null.

How do I solve this problem?

Answer 1

I got the solution for this on the internet somewhere

Brian from Coinbase here. It looks like you are hitting the API to generate a new payment button for each page load which, depending on the amount of traffic you get, could trigger our rate limiting either internally or through CloudFlare.

We currently have the merchant create button api limited to 10,000 calls per day internally, for example, for most merchants.

A better approach would be to hit the API once for each product (or if the price changes) and store the resulting 'code' parameter. If you save this in your database you can reuse it on every page load. This will help your pages load faster also.

More details: www.coinbase.com/api/doc/1.0/buttons/create.html

Hope it helps!

Answer 2

You can use the following code for generating button for payment:

$apikey ="***************"; 
   $apisecret = "************************";
   $nonce = sprintf('%0.0f',round(microtime(true) * 1000000));

   $url = "https://api.sandbox.coinbase.com/v1/buttons?nonce=" . $nonce;

   $parameters = [];
   $parameters["button"]["name"] = "Checkout Invoice";
   $parameters["button"]["custom"] = $orderId;
   $parameters["button"]["price_string"] = $priceString;
   $parameters["button"]["type"] = "buy_now";
   $parameters["button"]["subscription"] = false;
   $parameters["button"]["price_currency_iso"] = "USD";
   $parameters["button"]["description"] = "Checkout Invoice";
   $parameters["button"]["style"] = "custom_large";
   $parameters["button"]["include_email"] = true;
   $parameters["button"]["callback_url"] = url("bitcoin/callback");
   $parameters = http_build_query($parameters, true);



  $signature = hash_hmac("sha256", $nonce . $url . $parameters, $apisecret);

   $ch = curl_init();

   curl_setopt_array($ch, array(
       CURLOPT_URL => $url,
       CURLOPT_RETURNTRANSFER => true,
       CURLOPT_HTTPHEADER => array(
           "ACCESS_KEY: " . $apikey,
           "ACCESS_NONCE: " . $nonce,
           "ACCESS_SIGNATURE: " . $signature
       )));

   curl_setopt_array($ch, array(
       CURLOPT_POSTFIELDS => $parameters,
       CURLOPT_POST => true,
   ));

   $response = curl_exec($ch);

   curl_close($ch);

   $decodeResponse = json_decode($response);