HOWTO: Set Up a Testnet and Deploy Custom Contracts

[Kukovec]

closes #9

This HOWTO describes the steps required to:

• Create a local Stellar network
• Write and compile a custom contract
• Deploy said contract to a (test)net and invoke it

Rendered doc

[Kukovec]

In case someone wants a quick contract to play around with, here's a lib.rs from Foo. It has a map of vectors in addition to an integer counter.

#![no_std]
use soroban_sdk::{contract, contractimpl, log, symbol_short, Env, Symbol, Vec, Map, Address};

const VAL: Symbol = symbol_short!("VAL");
const ADDRS: Symbol = symbol_short!("ADDRS");

#[contract]
pub struct FooContract;

type AddrMap = Map<u32, Vec<Address>>;

#[contractimpl]
impl FooContract {
    pub fn bar(env: Env, addr: Address) -> u32 {
        // Get the current count.
        let mut val: u32 = env.storage().instance().get(&VAL).unwrap_or(1); // If no value set, assume 0.
        log!(&env, "val: {}", val);

        // If val < 50, double, else set to 1
        val = if val < 5 { 2 * val } else { 1 };

        // Save val.
        env.storage().instance().set(&VAL, &val);

        // Save the caller, for the current counter value
        let mut addrs: AddrMap = env.storage().instance().get(&ADDRS).unwrap_or(AddrMap::new(&env));

        let mut new_vec = addrs.get(val).unwrap_or(Vec::new(&env));
        new_vec.push_back(addr);

        addrs.set(val, new_vec);

        // Save addrs.
        env.storage().instance().set(&ADDRS, &addrs);

        // The contract instance will be bumped to have a lifetime of at least 100 ledgers if the current expiration lifetime at most 50.
        // If the lifetime is already more than 100 ledgers, this is a no-op. Otherwise,
        // the lifetime is extended to 100 ledgers. This lifetime bump includes the contract
        // instance itself and all entries in storage().instance(), i.e, COUNTER.
        env.storage().instance().extend_ttl(50, 100);

        // Return val to the caller.
        val
    }

    pub fn baz(env: Env) -> AddrMap {
        return env.storage().instance().get(&ADDRS).unwrap_or(AddrMap::new(&env));
    }
}

mod test;

[Kukovec]

As we've discussed, we should create a megacontract in the future, and when we do I'll link it here as an example.

[konnov]

I have made it through the first half of the doc! It's nice and detailed. I left a few comments. Stopped at a blocker that requires me to find a contract somewhere. Please add one.

[konnov]

Since you mention Nixos above, we should add a link to setting up docker on Nixos: https://nixos.wiki/wiki/Docker

[konnov]

I have made till this point. Could you add an example contract in the repo, so all of us could the same one to make sure that we have our setup working.

[Kukovec]

Might as well take this chance to set up the megacontract repo going forward.

[Kukovec]

#11 for tracking

[Kukovec]

#12

[thpani]

There is soroban contract init --with-example, you could just use one of those.

[Kukovec]

I have made it through the first half of the doc! It's nice and detailed. I left a few comments. Stopped at a blocker that requires me to find a contract somewhere. Please add one.

#10 (comment)

[konnov]

I have made it through the first half of the doc! It's nice and detailed. I left a few comments. Stopped at a blocker that requires me to find a contract somewhere. Please add one.

#10 (comment)

Yeah, that's where I got stuck. Why would not you just commit the whole contract layout, e.g., under examples/contracts

[thpani]

Yeah, got my first contract deployed! Thanks Jure!

I left I few comments that I needed to get everything going, I think we should wait for someone else to follow along and see if those are quirks of my local setup or needed in general.

[thpani]

afaict soroban keys generate fails with the funding error only if it cannot make a connection to the node. Otherwise, the config identity fund is not needed.

[andrey-kuprianov]

I had to provide also the passphrase, otherwise the command fails:

Suggested change

	soroban contract deploy --wasm <CONTRACT>.wasm --source <AGENT> --network <NETWORK>
	soroban contract deploy --wasm <CONTRACT>.wasm --source <AGENT> --network <NETWORK> --network-passphrase <PASSPHRASE>

[andrey-kuprianov]

In fact for my setup, this step was failing with

error: provided network passphrase "soroban testnet" does not match the server: "Test SDF Network ; September 2015"

Only when the previous step was executed exactly with this passphrase, i.e.

soroban config network add testnet --rpc-url "http://localhost:8000/soroban/rpc" --network-passphrase "Test SDF Network ; September 2015"

and then all arguments repeated in the deploy call like that

soroban contract deploy --wasm target/wasm32-unknown-unknown/release/hello_world.wasm --source alice --network testnet --network-passphrase "Test SDF Network ; September 2015" --rpc-url "http://localhost:8000/soroban/rpc

it did succeed...

[Kukovec]

I think this might be related to https://github.com/freespek/solarkraft/pull/10/files#r1565784375, since the node is joining an existing testnet. It should work as is written with --local.

[thpani]

We got this working for the dev team quite some time ago, and the Soroban "getting started" docs are probably a more up-to-date resource: https://developers.stellar.org/docs/smart-contracts/getting-started