Technical Guides¶

SmartCash Wallet Integration¶

SmartCash NodeClient is a fork of Bitcoin and the majority of functionality included in the SmartCash NodeClient Daemon can be integrated in a similar manner. Key differences relate to customizations to existing JSON-RPC commands to support unique functionalities such as InstantPay. These differences, as well as more general information, are summarized below.

General Information: SmartCash is a “Proof of Work” blockchain with attributes similar to that of Bitcoin.
1. Block Time: ~55 seconds per Block
2. Blockchain Confirmations: 6 Confirmations (or 2 in the case of InstantPay)
3. Github Source: https://github.com/SmartCash/Core-Smart
4. Release Link: https://github.com/SmartCash/Core-Smart/releases/
JSON-RPC Interface: The majority of Bitcoin JSON-RPC commands are unchanged making integration into existing systems relatively straightforward. For a complete listing of RPC commands see the command-line options.

It’s worth noting that several key Transaction-related JSON-RPC commands have been modified to support InstantPay.
Block Hashing Algorithm: SmartCash uses the “keccak” algorithm in place of SHA256 used in Bitcoin. It’s important to note, however, that this only affects the hashing of the Block itself. All other internals utilize SHA256 hashes (transactions, merkle root, etc) which allows for most existing libraries to work in the SmartCash ecosystem.
Supporting Libraries: Due to the aforementioned differences in Hashing Algorithm only minor adjustments are required before using Bitcoin libraries on the SmartCash network. The most popular libraries have already been ported to SmartCash which has enabled support for most major programming languages. These resources are outlined in the SDK Resources section of this document.

Integration Notes¶

API Services¶

Several API services exist to facilitate quick and easy integration with the SmartCash network for services including:

Transaction broadcasting
Exchange rates
Currency conversion
Invoice generation

API Services are typically leveraged to eliminate that requirement of running your own infrastructure to support blockchain interactions. This includes mechanisms such as:

Forming and Broadcasting a Transaction to the network.
Address generation using HD Wallets.
Payment Processing using WebHooks.

There are a variety of options for supporting these methods, with the key differentiator being the pricing model included and supported features. The following list of API Providers attempts to outline these key features/differentiators and also includes a link to related documentation.

Insight¶

https://insight.smartcash.cc/api https://github.com/SmartCash/smart-insight-api

The open-source Insight REST API provides you with a convenient, powerful and simple way to read data from the SmartCash network and build your own services with it. A practical guide to getting started with the Insight API and Insight UI block explorer is available here.

Features: Transaction Broadcast, WebSocket Notifications.
Pricing Model: Free / Open Source
Documentation: https://github.com/bitpay/insight-api

CoinPayments¶

https://www.coinpayments.net

CoinPayments is an integrated payment gateway for cryptocurrencies such as SmartCash. Shopping cart plugins are available for all popular webcarts used today. CoinPayments can help you set up a new checkout, or integrate with your pre-existing checkout.

Features: Invoicing, Exchange Rates, WebHook Callbacks. CoinPayments holds Private Keys on their server allowing merchant to withdraw funds in Cryptocurrency or convert to Fiat.
Integrations: aMember Pro, Arastta, Blesta, BoxBilling, Drupal, Ecwid, Hikashop, Magento, OpenCart, OSCommerce, PrestaShop, Tomato Cart, WooCommerce, Ubercart, XCart, ZenCart
Pricing Model: 0.5% Processing Fee (https://www.coinpayments.net/help-fees)
Documentation: https://www.coinpayments.net/apidoc

Mycryptocheckout¶

https://mycryptocheckout.com/

Accept cryptocurrency payments for WordPress.

0% transaction fees
Peer-to-peer payments
Use any crypto wallet you want
No KYC or product restrictions
Accept 93+ coins

Anypay¶

https://anypay.global/

Anypay is Fast, Private, No-Fees, Multi-coin Point of Sale.

SDK Resources¶

SDKs (Software Development Kits) are used to accelerate the design and development of a product for the SmartCash Network. These resources can either be used to interface with an API provider or for the creation of standalone applications by forming transactions and/or performing various wallet services.

SmartCash Developer Guide¶

https://github.com/SmartCash/Core-Smart

The SmartCash Developer Guide aims to provide the information you need to understand SmartCash and start building SmartCash-based applications. To make the best use of this documentation, you may want to install the current version of SmartCash Core, either from source or from a pre-compiled executable.

Documentation: https://github.com/SmartCash/Core-Smart

SmartCard SDK¶

https://github.com/SmartCash/Core-Smart

Easy create your smartcard from your website

Open with button click - Auto Open False

<button type="submit" onclick="SmartCard.openModal()">Create SmartCard</button><script type="text/javascript" src="https://card.smartcash.cc/js/v1/smartcard.js"></script>

Open on page load - Auto Open True

<script type="text/javascript" src="https://card.smartcash.cc/js/v1/smartcard.js"
data-auto-open="true">
data-generate-csv="true"></script>

Add CSV to zip - Generate CSV True

<script type="text/javascript" src="https://card.smartcash.cc/js/v1/smartcard.js"
data-auto-open="true"
data-generate-csv="true"></script>

Python: python-smartcashrpc¶

https://github.com/leoreinaux/python-smartcashrpc

python-smartcashrpc AuthServiceProxy is an improved version of python-jsonrpc.

sends Basic HTTP authentication headers.
parses all JSON numbers that look like floats as Decimal, and serializes Decimal values to JSON-RPC connections.
Documentation: https://github.com/leoreinaux/python-smartcashrpc/blob/master/README.rst
Repository: https://github.com/leoreinaux/python-smartcashrpc

PHP: Bitcoin-PHP¶

https://github.com/Bit-Wasp/bitcoin-php

Bitcoin-PHP is an implementation of Bitcoin with support for SmartCash using mostly pure PHP.

Platform: PHP
Documentation: https://github.com/Bit-Wasp/bitcoin-php/blob/master/doc/Introduction.md
Repository: https://github.com/Bit-Wasp/bitcoin-php

Python: PyCoin¶

https://github.com/richardkiss/pycoin

PyCoin is an implementation of a bunch of utility routines that may be useful when dealing with Bitcoin and SmartCash. It has been tested with Python 2.7, 3.6 and 3.7.

Platform: Python
Documentation: https://pycoin.readthedocs.io/en/latest/
Repository: https://github.com/richardkiss/pycoin

.NET: NBitcoin¶

https://github.com/MetacoSA/NBitcoin

NBitcoin is the most complete Bitcoin library for the .NET platform, and has been patched to include support for SmartCash. It implements all most relevant Bitcoin Improvement Proposals (BIPs) and SmartCash Improvement Proposals (DIPs). It also provides low level access to SmartCash primitives so you can easily build your application on top of it.

Platform: .NET
Documentation: https://programmingblockchain.gitbooks.io/programmingblockchain/content/
Repository: https://github.com/MetacoSA/NBitcoin

BlockCypher¶

https://www.blockcypher.com

BlockCypher also offers client SDKs.

Platform: Ruby, Python, Java, PHP, Go, NodeJS
Repositories: https://www.blockcypher.com/dev/SmartCash/#blockcypher-supported-language-sdks

GoCoin¶

https://gocoin.com

Platform: JavaScript, PHP, Java, Ruby, .NET, Python
Repositories: https://gocoin.com/docs

InstantPay¶

InstantPay is a feature provided by the SmartCash network that allows for 0-confirmation transactions to be safely accepted by Merchants and other service providers. Secured by the Smartnode Network, this mechanism eliminates the risk of a “Double Spend” by locking transaction inputs for a given transaction at a protocol level.

InstantPay Transactions vs. Standard Transactions¶

From an integration perspective there are only minor differences between an InstantPay Transaction and a Standard Transaction. Both transaction types are formed in the same way and are signed using the same process; the key difference is the fee structure and input requirements for InstantPay.

Fee Structure: InstantPay utilizes a “per-input” fee of 0.001 SmartCash per Input.
Input Requirements: All inputs for an InstantPay transaction must have at least 2 confirmations.
Amount: Total amount InstantPay limits the total coins that can be locked in a transaction to %1 SMART and must less than 100k. You may need to use a normal transaction to split large deposits before you can send with InstantPay.

In the event that a given transaction does not meet both criteria it will revert to a standard transaction.

Receiving InstantPay Transactions¶

InstantPay transactions are handled in the same way as a Standard Transaction, typically through JSON-RPC, Insight API, or an internal notification script / service that is configured at a server level.

JSON-RPC: The following RPC commands will include InstantPay-related information. Within the response you’ll find an “InstantLock” field the status of a given Transaction. This true/false (boolean) value will indicate whether an InstantPay has been observed.
Insight API: Insight API can be used to detect InstantPay transactions and to push notifications to clients using WebSockets. The API can also be manually polled to retrieve Transaction information including InstantPay status.

Broadcasting InstantPay Transactions¶

InstantPay Transactions can be constructed and broadcast using an approach similar to Standard Transactions. Provided the InstantPay Fee Structure and Input Requirements are met, an InstantPay can be broadcast using JSON-RPC or Insight API as a Raw Transaction.

JSON-RPC: The “SendRawTransaction” RPC command can be utilized to broadcast a raw transaction using InstantPay. When utilizing this command be sure to set both optional parameters as “true”

sendrawtransaction "hexstring" ( allowhighfees InstantPay ) sendrawtransaction "hexstring" true true

More Information: https://github.com/SmartCash/Core-Smart/
Insight API: Raw Transactions can also be broadcast as an InstantPay using Insight API. In this case all that is required is to POST the raw transaction using the /tx/sendix route.

More Information: https://github.com/SmartCash/Core-Smart/

Additional Resources¶

The following resources provide additional information about InstantPay and are intended to help provide a more complete understanding of the underlying technologies.

Vending Machines¶

Price Tickers¶

You can add a simple price ticket widget to your website using the simple code snippet generator from CoinGecko.

QR Codes¶

Many wallets are capable of generating QR codes which can be scanned to simplify entry of the SmartCash address. Printing these codes or posting the on your website makes it easy to receive payment and tips in SmartCash, both online and offline.

In SmartCash NodeClient, go to the Receive tab, generate an address if necessary, and double-click it to display a QR code. Right click on the QR code and select Save Image to save a PNG file.