ERIC MACUS

ERIC MACUS

1647619200

UTXO On Substrate: A Substrate UTXO workshop

UTXO on Substrate

Note: this workshop is presently not actively maintained and is using older versions of all dependancies than presently used in substrate.

A UTXO chain implementation on Substrate, with two self-guided workshops. Original UXTO inspiration by Dmitriy Kashitsyn.

Substrate Version: 2.0.0-rc6. For educational purposes only.

Table of Contents

Installation: Setting up Rust & Substrate dependencies

UI Demo: Demo of UTXO implementation in a simple UI

Beginner Workshop: A self guided, 1 hour workshop that familiarizes you with Substrate.

Advanced Workshop: A self guided, 2 hour video tutorial, that teaches you how to build a UTXO blockchain from scratch.

Helpful Resources: Additional supporting documentation and references for troubleshooting.

Installation

1. Install or update Rust

curl https://sh.rustup.rs -sSf | sh

# On Windows, download and run rustup-init.exe
# from https://rustup.rs instead

rustup update nightly
rustup target add wasm32-unknown-unknown --toolchain nightly
rustup update stable

2. Clone this workshop

Clone your copy of the workshop codebase

git clone https://github.com/substrate-developer-hub/utxo-workshop.git

UI Demo

In this UI demo, you will interact with the UTXO blockchain via the Polkadot UI.

The following example takes you through a scenario where:

  • Alice already owns a UTXO of value 100 upon genesis
cargo build --release
  • Alice sends Bob a UTXO with value 50, tipping the remainder to validators
./target/release/utxo-workshop --dev --tmp

Compile and build a release node

Start a node. The --dev flag will start a single mining node, and the --tmp flag will start it in a new temporary directory.

In the console note the helper printouts. In particular, notice the default account Alice already has 100 UTXO within the genesis block.

Open Polkadot JS making sure the client is connected to your local node by going to Settings > General and selecting Local Node in the remote node dropdown.

Declare custom datatypes in PolkadotJS as the frontend cannot automatically detect this information. To do this, go to Settings > Developer tab and paste in the following JSON:

{
  "Address": "AccountId",
  "LookupSource": "AccountId",
  "Value": "u128",
  "TransactionInput": {
    "outpoint": "Hash",
    "sigscript": "H512"
  },
  "TransactionOutput": {
    "value": "Value",
    "pubkey": "Hash"
  },
  "Transaction": {
    "inputs": "Vec<TransactionInput>",
    "outputs": "Vec<TransactionOutput>"
  },
  "Difficulty": "U256",
  "DifficultyAndTimestamp": {
    "difficulty": "Difficulty",
    "timestamp": "Moment"
  },
  "Public": "H256"
}

Confirm that Alice already has 100 UTXO at genesis. In Chain State > Storage, select utxo. Input the hash 0x76584168d10a20084082ed80ec71e2a783abbb8dd6eb9d4893b089228498e9ff. Click the + notation to query blockchain state.

Notice that:

  • This UTXO has a value of 100
  • This UTXO belongs to Alice's pubkey. You use the subkey tool to confirm that the pubkey indeed belongs to Alice

Spend Alice's UTXO, giving 50 to Bob. In the Extrinsics tab, invoke the spend function from the utxo pallet, using Alice as the transaction sender. Use the following input parameters:

  • outpoint: 0x76584168d10a20084082ed80ec71e2a783abbb8dd6eb9d4893b089228498e9ff
  • sigscript: 0x6ceab99702c60b111c12c2867679c5555c00dcd4d6ab40efa01e3a65083bfb6c6f5c1ed3356d7141ec61894153b8ba7fb413bf1e990ed99ff6dee5da1b24fd83
  • value: 50
  • pubkey: 0x8eaf04151687736326c9fea17e25fc5287613693c912909cb226aa4794f26a48

Verify that your transaction succeeded. In Chain State, look up the newly created UTXO hash: 0xdbc75ab8ee9b83dcbcea4695f9c42754d94e92c3c397d63b1bc627c2a2ef94e6 to verify that a new UTXO of 50, belonging to Bob, now exists! Also you can verify that Alice's original UTXO has been spent and no longer exists in UtxoStore.

Coming soon: A video walkthrough of the above demo.

Beginner Workshop

Estimated time: 2 hours

In this workshop you will:

  • Get familiar with basic Rust and Substrate functionality
  • Prevent malicious users from sending bad UTXO transactions

Your challenge is to fix the code such that:

  1. The Rust compiler compiles without any errors
  2. All tests in utxo.rs pass, ensuring secure transactions

Directions

  1. Checkout the workshop branch. The Master branch has the solutions, so don't peek!
git fetch origin workshop:workshop
git checkout workshop
  1. Cd into the base directory. Run the test using: cargo test -p utxo-runtime.
compiling utxo-runtime v2.0.0 (/Users/nicole/Desktop/utxo-workshop/runtime)
error[E0433]: failed to resolve: use of undeclared type or module `H512`
   --> /Users/nicole/Desktop/utxo-workshop/runtime/src/utxo.rs:236:31
    |
236 |             input.sigscript = H512::zero();
    |                               ^^^^ use of undeclared type or module `H512`

...

Your first task: fix all the compiler errors! Hint: Look for the TODO comments in utxo.rs to see where to fix errors.

Once your code compiles, it's now time to fix the 8 failing tests!

failures:
    utxo::tests::attack_by_double_counting_input
    utxo::tests::attack_by_double_generating_output
    utxo::tests::attack_by_over_spending
    utxo::tests::attack_by_overflowing_value
    utxo::tests::attack_by_permanently_sinking_outputs
    utxo::tests::attack_with_empty_transactions
    utxo::tests::attack_with_invalid_signature
    utxo::tests::test_simple_transaction
  1. In utxo.rs, edit the logic in validate_transaction() function to make all tests pass.
running 8 tests
test utxo::tests::attack_by_overflowing_value ... ok
test utxo::tests::attack_by_double_counting_input ... ok
test utxo::tests::attack_by_double_generating_output ... ok
test utxo::tests::attack_by_over_spending ... ok
test utxo::tests::attack_with_empty_transactions ... ok
test utxo::tests::attack_with_invalid_signature ... ok
test utxo::tests::attack_by_permanently_sinking_outputs ... ok
test utxo::tests::test_simple_transaction ... ok

Advanced Workshop

VIDEO TUTORIALS COMING SOON

Estimated time: 2 hours

In this workshop, you will implement this UTXO project from scratch using Substrate.

You will learn:

  • How to implement the UTXO ledger model on Substrate
  • How to secure UTXO transactions against attacks
  • How to seed genesis block with UTXOs
  • How to reward block validators in this environment
  • How to customize transaction pool logic on Substrate
  • Good coding patterns for working with Substrate & Rust, including testing and refactoring

Checkout the startercode branch to get the boilerplate for this workshop.

git fetch origin startercode:startercode
git checkout startercode

Helpful Resources

Author: substrate-developer-hub
Source Code: https://github.com/substrate-developer-hub/utxo-workshop
License: Unlicense License

#blockchain #substrate 

What is GEEK

Buddha Community

UTXO On Substrate: A Substrate UTXO workshop
ERIC MACUS

ERIC MACUS

1647619200

UTXO On Substrate: A Substrate UTXO workshop

UTXO on Substrate

Note: this workshop is presently not actively maintained and is using older versions of all dependancies than presently used in substrate.

A UTXO chain implementation on Substrate, with two self-guided workshops. Original UXTO inspiration by Dmitriy Kashitsyn.

Substrate Version: 2.0.0-rc6. For educational purposes only.

Table of Contents

Installation: Setting up Rust & Substrate dependencies

UI Demo: Demo of UTXO implementation in a simple UI

Beginner Workshop: A self guided, 1 hour workshop that familiarizes you with Substrate.

Advanced Workshop: A self guided, 2 hour video tutorial, that teaches you how to build a UTXO blockchain from scratch.

Helpful Resources: Additional supporting documentation and references for troubleshooting.

Installation

1. Install or update Rust

curl https://sh.rustup.rs -sSf | sh

# On Windows, download and run rustup-init.exe
# from https://rustup.rs instead

rustup update nightly
rustup target add wasm32-unknown-unknown --toolchain nightly
rustup update stable

2. Clone this workshop

Clone your copy of the workshop codebase

git clone https://github.com/substrate-developer-hub/utxo-workshop.git

UI Demo

In this UI demo, you will interact with the UTXO blockchain via the Polkadot UI.

The following example takes you through a scenario where:

  • Alice already owns a UTXO of value 100 upon genesis
cargo build --release
  • Alice sends Bob a UTXO with value 50, tipping the remainder to validators
./target/release/utxo-workshop --dev --tmp

Compile and build a release node

Start a node. The --dev flag will start a single mining node, and the --tmp flag will start it in a new temporary directory.

In the console note the helper printouts. In particular, notice the default account Alice already has 100 UTXO within the genesis block.

Open Polkadot JS making sure the client is connected to your local node by going to Settings > General and selecting Local Node in the remote node dropdown.

Declare custom datatypes in PolkadotJS as the frontend cannot automatically detect this information. To do this, go to Settings > Developer tab and paste in the following JSON:

{
  "Address": "AccountId",
  "LookupSource": "AccountId",
  "Value": "u128",
  "TransactionInput": {
    "outpoint": "Hash",
    "sigscript": "H512"
  },
  "TransactionOutput": {
    "value": "Value",
    "pubkey": "Hash"
  },
  "Transaction": {
    "inputs": "Vec<TransactionInput>",
    "outputs": "Vec<TransactionOutput>"
  },
  "Difficulty": "U256",
  "DifficultyAndTimestamp": {
    "difficulty": "Difficulty",
    "timestamp": "Moment"
  },
  "Public": "H256"
}

Confirm that Alice already has 100 UTXO at genesis. In Chain State > Storage, select utxo. Input the hash 0x76584168d10a20084082ed80ec71e2a783abbb8dd6eb9d4893b089228498e9ff. Click the + notation to query blockchain state.

Notice that:

  • This UTXO has a value of 100
  • This UTXO belongs to Alice's pubkey. You use the subkey tool to confirm that the pubkey indeed belongs to Alice

Spend Alice's UTXO, giving 50 to Bob. In the Extrinsics tab, invoke the spend function from the utxo pallet, using Alice as the transaction sender. Use the following input parameters:

  • outpoint: 0x76584168d10a20084082ed80ec71e2a783abbb8dd6eb9d4893b089228498e9ff
  • sigscript: 0x6ceab99702c60b111c12c2867679c5555c00dcd4d6ab40efa01e3a65083bfb6c6f5c1ed3356d7141ec61894153b8ba7fb413bf1e990ed99ff6dee5da1b24fd83
  • value: 50
  • pubkey: 0x8eaf04151687736326c9fea17e25fc5287613693c912909cb226aa4794f26a48

Verify that your transaction succeeded. In Chain State, look up the newly created UTXO hash: 0xdbc75ab8ee9b83dcbcea4695f9c42754d94e92c3c397d63b1bc627c2a2ef94e6 to verify that a new UTXO of 50, belonging to Bob, now exists! Also you can verify that Alice's original UTXO has been spent and no longer exists in UtxoStore.

Coming soon: A video walkthrough of the above demo.

Beginner Workshop

Estimated time: 2 hours

In this workshop you will:

  • Get familiar with basic Rust and Substrate functionality
  • Prevent malicious users from sending bad UTXO transactions

Your challenge is to fix the code such that:

  1. The Rust compiler compiles without any errors
  2. All tests in utxo.rs pass, ensuring secure transactions

Directions

  1. Checkout the workshop branch. The Master branch has the solutions, so don't peek!
git fetch origin workshop:workshop
git checkout workshop
  1. Cd into the base directory. Run the test using: cargo test -p utxo-runtime.
compiling utxo-runtime v2.0.0 (/Users/nicole/Desktop/utxo-workshop/runtime)
error[E0433]: failed to resolve: use of undeclared type or module `H512`
   --> /Users/nicole/Desktop/utxo-workshop/runtime/src/utxo.rs:236:31
    |
236 |             input.sigscript = H512::zero();
    |                               ^^^^ use of undeclared type or module `H512`

...

Your first task: fix all the compiler errors! Hint: Look for the TODO comments in utxo.rs to see where to fix errors.

Once your code compiles, it's now time to fix the 8 failing tests!

failures:
    utxo::tests::attack_by_double_counting_input
    utxo::tests::attack_by_double_generating_output
    utxo::tests::attack_by_over_spending
    utxo::tests::attack_by_overflowing_value
    utxo::tests::attack_by_permanently_sinking_outputs
    utxo::tests::attack_with_empty_transactions
    utxo::tests::attack_with_invalid_signature
    utxo::tests::test_simple_transaction
  1. In utxo.rs, edit the logic in validate_transaction() function to make all tests pass.
running 8 tests
test utxo::tests::attack_by_overflowing_value ... ok
test utxo::tests::attack_by_double_counting_input ... ok
test utxo::tests::attack_by_double_generating_output ... ok
test utxo::tests::attack_by_over_spending ... ok
test utxo::tests::attack_with_empty_transactions ... ok
test utxo::tests::attack_with_invalid_signature ... ok
test utxo::tests::attack_by_permanently_sinking_outputs ... ok
test utxo::tests::test_simple_transaction ... ok

Advanced Workshop

VIDEO TUTORIALS COMING SOON

Estimated time: 2 hours

In this workshop, you will implement this UTXO project from scratch using Substrate.

You will learn:

  • How to implement the UTXO ledger model on Substrate
  • How to secure UTXO transactions against attacks
  • How to seed genesis block with UTXOs
  • How to reward block validators in this environment
  • How to customize transaction pool logic on Substrate
  • Good coding patterns for working with Substrate & Rust, including testing and refactoring

Checkout the startercode branch to get the boilerplate for this workshop.

git fetch origin startercode:startercode
git checkout startercode

Helpful Resources

Author: substrate-developer-hub
Source Code: https://github.com/substrate-developer-hub/utxo-workshop
License: Unlicense License

#blockchain #substrate 

Larry Kessler

Larry Kessler

1617355640

Attend The Full Day Hands-On Workshop On Reinforcement Learning

The Association of Data Scientists (AdaSci), a global professional body of data science and ML practitioners, is holding a full-day workshop on building games using reinforcement learning on Saturday, February 20.

Artificial intelligence systems are outperforming humans at many tasks, starting from driving cars, recognising images and objects, generating voices to imitating art, predicting weather, playing chess etc. AlphaGo, DOTA2, StarCraft II etc are a study in reinforcement learning.

Reinforcement learning enables the agent to learn and perform a task under uncertainty in a complex environment. The machine learning paradigm is currently applied to various fields like robotics, pattern recognition, personalised medical treatment, drug discovery, speech recognition, and more.

With an increase in the exciting applications of reinforcement learning across the industries, the demand for RL experts has soared. Taking the cue, the Association of Data Scientists, in collaboration with Analytics India Magazine, is bringing an extensive workshop on reinforcement learning aimed at developers and machine learning practitioners.

#ai workshops #deep reinforcement learning workshop #future of deep reinforcement learning #reinforcement learning #workshop on a saturday #workshop on deep reinforcement learning

Rust Blockchain

Rust Blockchain

1643578320

Substrate Archive: Blockchain Indexing Engine

Substrate Archive


Blockchain Indexing Engine

Run alongside a substrate-backed chain to index all Blocks, State, and Extrinsic data into PostgreSQL.

Usage

The schema for the PostgreSQL database is described in the PDF File at the root of this directory.

Examples for how to use substrate-archive are in the examples/ directory

Prerequisites

Extended requirements list found in the wiki

  • depending on the chain you want to index, ~60GB free space
  • PostgreSQL with a database ready for lots of new data
  • Substrate-based Blockchain running with RocksDB as the backend
  • Substrate-based Blockchain running under --pruning=archive

Install The CLI

The CLI

The CLI is an easier way to get started with substrate-archive. It provides a batteries-included binary, so that you don't have to write any rust code. All thats required is setting up a PostgreSQL DB, and modifying a config file. More information in the wiki

The Node-Template CLI

The node-template CLI (in /bin/node-template-archive) is provided as an example of implementing substrate-archive for your chain.

Quick Start

git clone https://github.com/paritytech/substrate-archive.git
# Set up the databases
source ./substrate-archive/scripts/up.sh # Run ./scripts/down.sh to drop the database
cd substrate-archive/bin/polkadot-archive/
# Start the normal polkadot node with `pruning` set to `archive`
polkadot --chain=polkadot --pruning=archive
# Start up the substrate-archive node. `chain` can be one of `polkadot`, `kusama`, or `westend`.
cargo run --release --  -c test_conf.toml --chain=polkadot

You can access the help dialog via cargo run --release -- --help. Note that up and down scripts are meant for convenience and are not meant to be complete. Look in the wiki for more information about the database setup.

FAQ

Contributing

Contributors are welcome!

Read the Doc

Documentation

You can build the documentation for this crate by running cargo doc. More Docs here

Troubleshooting

Archive fails to start with a too many open files error.

Because of the way a RocksDB Secondary Instance works, it requires that all the files of the primary instance remain open in the secondary instance. This could trigger the error on linux, but simply requires that you raise the max open files limit (ulimit):

  • With Docker: $ docker run --ulimit nofile=90000:90000 <image-tag>
  • For Current Shell Session: ulimit -a 90000
  • Permanantly Per-User
    • Edit /etc/security/limits.conf
# /etc/security/limits.conf
*           hard    nofile      4096
*           soft    nofile      1024
some_usr    hard    nofile      90000
some_usr    soft    nofile      90000
insipx      hard    nofile      90000
insipx      soft    nofile      90000
root        hard    nofile      90000
root        soft    nofile      90000

For macOS and Linux, a warning message will be raised on the startup when there is a low fd sources limit in the current system, but Windows won't have such a low fd limit warning.

Contact

You can contact us at:

# /etc/security/limits.conf
*           hard    nofile      4096
*           soft    nofile      1024
some_usr    hard    nofile      90000
some_usr    soft    nofile      90000
insipx      hard    nofile      90000
insipx      soft    nofile      90000
root        hard    nofile      90000
root        soft    nofile      90000

Download Details:
Author: paritytech
Source Code: https://github.com/paritytech/substrate-archive
License: GPL-3.0 License

#rust  #rustlang  #blockchain #substrate 

German Donnelly

German Donnelly

1593103980

Substrate Execute Block Code Walkthrough

Parity’s Joe Petrowski and Shawn Tabrizi give an introductory code walkthrough for the Substrate executive module, a Rust module for executing blocks in Substrate-based blockchains.

#substrate #rust module #substrate

ERIC MACUS

ERIC MACUS

1647568800

A Collaborative Workshop to Learn How To Use Substrate

substrate-beginner-workshop

A collaborative workshop to learn how to use Substrate

Overview

  1. Getting started with Substrate
  2. Running a local network
  3. Building a Proof-of-Existence (PoE) Blockchain
  4. Forkless upgrade of our local network

Setting Up The Bootnode

This workshop depends on two bootnodes running somewhere publicly accessible. In practice this will usually be two nodes on a single cloud vps such as Digital Ocean or Google Cloud. This document guides the workshop host through the process of setting up this configuration.

Base System

Create a new VPS starting with Ubuntu 18.04 with SSH permissions. Many of these commands need to be run as root, so it is convenient to start a persistent sudo session with sudo -i.

Nginx

We will use Nginx as a reverse proxy and to host a simple web page. Let's start by installing it.

apt install nginx

Confirm the server is working by going directly to your IP in the browser. Should see the nginx test page. The file you just viewed lives at /var/www/html/index.nginx-debian.html. This file is only used when a regular index.html file is not present. Let's create our own index file.

cd /var/www/html
vim index.html

Then paste in this content

<!DOCTYPE html>
<html>
	<head>
		<title>Denver Substrate Testnet</title>
		<style>
			body {
				width: 35em;
				margin: 0 auto;
			}
		</style>
	</head>
	<body>
		<h1>Denver Substrate Testnet</h1>
		<p>Thanks for joining our Substrate testnet!</p>

		<ul>
			<li>Follow along with <a href="https://substrate.dev/substrate-beginner-workshop/#/0/">The Workshop</a></li>
			<li>Clone the <a href="https://github.com/substrate-developer-hub/substrate-node-template">Substrate Node Template</a>.</li>
			<li>Download the <a href="spec.json">Chain Specification</a>.</li>
			<li>Download the <a href="alice.json">Prefunded Alice Key</a>.</li>
			<li>Connect to <a href="https://polkadot.js.org/apps?rpc=wss://denver.bootnodes.net/alice">Alice's Node</a></li>
			<li>Connect to <a href="https://polkadot.js.org/apps?rpc=wss://denver.bootnodes.net/bob">Bob's Node</a></li>
		</ul>

	</body>
</html>

We'll create those linked files later. Confirm the new webpage loads.

Adding SSL

We need a domain in order to use SSL. Register it and setup dns so it points to your server. This process varies a lot by registrar. When your domain loads the webpage we just created, you may proceed to setup SSL.

For setting up subdomains like sfbw.bootnodes.net just use an A record sfbw A 1.2.3.4 3600

Install certbot, a tool that makes it easy to register new SSL certificates.

add-apt-repository ppa:certbot/certbot
apt install python-certbot-nginx

Configure nginx to work as a reverse proxy for both Alice's and Bob's nodes

cd /etc/nginx/sites-available
vim sfbw.bootnodes.net

Replace the contents of the file with this

server {
  listen 80;

  server_name denver.bootnodes.net;

  root /var/www/html;
  index index.html;

  location / {
    try_files $uri $uri/ =404;
  }

  location /alice {
    proxy_buffers 16 4k;
    proxy_buffer_size 2k;
    proxy_pass http://localhost:9944;
    proxy_http_version 1.1;
  }

  location /bob {
    proxy_buffers 16 4k;
    proxy_buffer_size 2k;
    proxy_pass http://localhost:9945;
    proxy_http_version 1.1;
  }

# Uncomment these lines to enable reverse proxy for http rpcs as well
#  location /alice/rpc {
#    proxy_buffers 16 4k;
#    proxy_buffer_size 2k;
#    proxy_pass http://localhost:9933;
#    proxy_http_version 1.1;
#  }

#  location /bob/rpc {
#    proxy_buffers 16 4k;
#    proxy_buffer_size 2k;
#    proxy_pass http://localhost:9934;
#    proxy_http_version 1.1;
#  }
}

Enable the new config by linking it from sites-available to sites-enabled.

ln -s /etc/nginx/sites-available/sfbw.bootnodes.net /etc/nginx/sites-enabled/

Confirm config format is ok, and if it is, reload nginx.

# Check nginx config syntax
nginx -t

# Reload the server
systemctl reload nginx

Use certbot to setup ssl certbot --nginx -d sfbw.bootnodes.net --register-unsafely-without-email You could also fork over your email. It only goes to EFF. I chose not to redirect http, but we should experiment with it. If it doesn't break anything, we should do it.

Confirm your site loads with ssl https://sfbw.bootnodes.net

Build and Run Substrate Node

# First time around I did the apt/rustup installs manually
# Script also works as of 1Nov2019
curl https://getsubstrate.io -sSf | bash -s -- --fast

git clone https://github.com/substrate-developer-hub/substrate-node-template
cd substrate-node-template
cargo build --release # If cargo was _just_ installed, start a new shell so it's on your path

To test that our reverse proxy is working, we'll start a node at Alice's ports and confirm we can connect to it throug hApps, then do likewise for Bob's ports.

# Test Alice's ports
./target/release/node-template --dev

# Test Bob's ports
./target/release/node-template --dev --ws-port 9945 --rpc-port 9934 --port 30303

Confirm you can connect with hosted apps. On settings tab use wss://sfbw.bootnodes.net/alice and /bob.

Create a shared chainspec

Create a basic chainspec based on local testnet node-template build-spec --chain local > spec.json

Edit the name and id of the network, the root key, the prefunded accounts etc.

Before we can add bootnodes to the chainspec, we need to know their node identities. That means we need to start each node once to let it generate node keys.

Start Alice's node like node-template --chain=spec.json --alice Once the node starts, observe its node identity, then kill it with ^C. Repeat this for any other nodes you'd like in the chainspec's bootnodes section.

Now edit the chainspec again, adding each bootnode in the format

"bootNodes": [
    "/dns4/sfbw.bootnodes.net/tcp/30333/p2p/QmNdzun5tXSo7TPEntmujvU3eLEjTJKfXpJAvwp1ikpa6T",
    "/ip4/167.71.86.67/tcp/30333/p2p/QmdP4qG1ZSgzmsdFpBwuPAVWG9zjPRHV3dSkTT8v4TGP4J"
],

Warning: You should not delete the node's entire data directory from this point on. You may purge the chain with the purge-chain sub command, but if you delete the entire directory, it will delete the node key and change the node's identity.

Finally, publish the chainspec by copying it to the web directory

cp spec.json /var/www/html/spec.json

Comfirm you can access it over the web https://sfbw.bootnodes.net/spec.json

Startup scripts (optional)

If your nodes need many flags, it may be wise to make a startup script just so you don't mess it up live. I usually write one like this.

# Purge any old chain.
# Only wise for chains that will be restarted frequently (eg workshops)
# Long running chains should not be purged to avoid constant re-syncs
./target/release/node-template purge-chain --chain=spec.json -y

./target/release/node-template \
        --chain=spec.json \
        --alice \
        --ws-port 9994 \
        --rpc-port 9993

Share the prefunded account

Remember at that our website offers users to download the pre-funded key. Add the Alice key to apps and export it to json. Dev phrase

bottom drive obey lake curtain smoke basket hold race lonely fit walk //Alice I use password: Alice Upload the json key to the server

Host a frontend

Back in /root, clone the front end template git clone https://github.com/substrate-developer-hub/substrate-front-end-template/

Install yarn following https://yarnpkg.com/lang/en/docs/install/#debian-stable

curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -
echo "deb https://dl.yarnpkg.com/debian/ stable main" | sudo tee /etc/apt/sources.list.d/yarn.list
apt update
apt install yarn

install dependencies yarn modify production server to match your needs vim src/config/production.json and use wss://sfbw.bootnodes.net:9944

build production release with yarn build then move build output directory inside of web root mv build /var/www/html/front-end

This is where I'm stuck. Loading https://sfbw.bootnodes.net/front-end shows a blank page, and the console shows warnings about scripts that didn't load.

I've failed many different ways at this point, and rarely even succeeded.

For Workshop Leaders

If you are leading this workshop, you will need to ahve a bootnode running in advance. Steps (more like notes) to do that are provided in Setting Up The Bootnode.

Author: substrate-developer-hub
Source Code: https://github.com/substrate-developer-hub/substrate-beginner-workshop
License: MIT License

#blockchain #substrate