Snap Coin Core

A rust crate for developing with and for Snap Coin

Some General Tips

Default binary to string serialization is base36 (letters + numbers only).
Most helper functions (like build_block(...), build_transaction(...)) take a blockchain data provider (this is a trait!), which is a struct that can access basic blockchain data and perform certain fetches etc. These are most commonly core::Node.blockchain and api::Client.

Getting started

Installation

To utilize this library in your project run

cargo add snap_coin

Utilization

There are two main ways of connecting and interacting with a snap coin network

As a standalone node (DIFFICULT)

Your program becomes the node, and you have direct access over its blockchain, peers, connected nodes, status. This is best for when you need fast, direct access. This is not recommended if you are creating a program that a user might want to run along side a existing node or if the user would like to create more than one instance of this program. This is the fastest approach as you directly interface with the node, without any translation layer in between.

Create a new node instance (WARNING: Only one instance can exist in a program at once otherwise a panic will happen!)
```
let node: Arc<RwLock<Node>> = Node::new("./node-path", 8998); // Path where the node will be stored, port to host node
```
Notice how new() returns a Arc<RwLock<Node>> instead of just a node. This is due to the fact that the node is passed around the internal code a lot and this abstractions makes it async safe.
Call and access functions of the node
```
Node::submit_block(node.clone(), some_block).await?;
println!("Last block: {}", node.read().await.last_seen_block.dump_base_36());
```
Notice how we clone the node, and call a static function on the Node struct. WARNING: When accessing direct values from the Node struct, make sure to call node.read().await or node.write().await if the internal state of the node will be modified by this operation.

Full example:

use snap_coin::{build_block, crypto::keys::Private, node::node::Node};
use std::sync::Arc;
use tokio::sync::RwLock;

#[tokio::main]
async fn main() -> Result<(), anyhow::Error> {
    let node: Arc<RwLock<Node>> = Node::new("./node-path", 8998);

    let mut some_block = build_block(&node.read().await.blockchain, &vec![], Private::new_random().to_public()).await?; // Path where the node will be stored, port to host node
    #[allow(deprecated)] // This is deprecated because it only works on a not congested network, with only 1 miner. Okay for creating genesis blocks
    some_block.compute_pow()?;

    Node::submit_block(node.clone(), some_block).await?; // Notice we clone the node, and call a static function on the Node struct
    println!("Last block: {}", node.read().await.last_seen_block.dump_base36());

    Ok(())
}

As a Snap Coin API interface with an existing node (EASY)

This approach makes your program a API client to a node that is already hosted (like snap-coin-node) by your user. This approach is slower and does not have full direct access to the node, however, it is a lot more lightweight then the approach mentioned before. This should be used when there will be more then one instance of this program running, for example a wallet can just connect to a hosted node (by the user) instead of being its own node. It is important to understand that the node this client will be connecting too must be 100% trusted as it can modify, spoof, and fake all interactions with this program.

Connect to a already running (in a separate program) node, that has a Snap Coin API server exposed
```
let client = Client::connect("127.0.0.1:3003".parse().unwrap()).await?;
```

Call functions on the client to obtain and change blockchain / node state

println!("Last block: {}", client.get_block_hash_by_height(last_block_height).await?.unwrap().dump_base36());

Full Example:

use snap_coin::{api::client::Client, blockchain_data_provider::BlockchainDataProvider, build_block, crypto::keys::Private, node::node::Node};

#[tokio::main]
async fn main() -> Result<(), anyhow::Error> {
    let client = Client::connect("127.0.0.1:3003".parse().unwrap()).await?; // Connect to a local node API

    let mut some_block = build_block(&client, &vec![], Private::new_random().to_public()).await?; // Path where the node will be stored, port to host node
    #[allow(deprecated)] // This is deprecated because it only works on a not congested network, with only 1 miner. Okay for creating genesis blocks
    some_block.compute_pow()?;

    client.submit_block(some_block).await??; // NOTE: This function is not part of the BlockchainDataProvider trait
    let last_block_height = client.get_height().await?.saturating_sub(1); // NOTE: using saturating sub because height is a usize to avoid overflow
    println!("Last block: {}", client.get_block_hash_by_height(last_block_height).await?.unwrap().dump_base36()); // unwrap is okay because we know a block exists since we just added one

    Ok(())
}

Documentation and Development Reference

Available here: rust.rs

Support this Project

You can support this project in many ways, but it is best to just develop and use Snap Coin. I take pride in this project, and by extent in this code. You can help us grow, as Snap Coin is a community effort, by creating apps that utilize Snap Coin, trading, using it as a medium of exchange for things like jobs.

Help Develop Snap Coin

This repo is always available for pull requests, i highly incentivize reading the code, documentation, and making new features. If you need any help, reach out to me on discord @ice.is.this or via email ice.is.this@gmail.com. Any issues can be reported in the issues tab.

Join the discord

Join and grow the community: discord.gg

Donate

You can buy the developer a coffee and help me keep my motivation:

Snap Coin: 60bamx9k23wcbv6m4xo26h4lsgxwlb83wv2nf1n0hnnatkj9vx

Bitcoin: bc1qacw3l33kzdg96tu268az3chsyrg3pcup0dat9j

Etherum: 0xef98b5ea67248e8a3ee4f4d3674c8ebb2be4e39a

Solana: 8ST3miN2KLdTNXa7pkK1g2qFB3xKzpe1bvCC2QuVBDHG

BNB Smart Chain 0xef98b5ea67248e8a3ee4f4d3674c8ebb2be4e39a

snap-coin 1.0.3