Local Polkadot

Have you ever tried interacting with the Polkadot network using polkadot.js.org/apps and found it to be frustratingly slow?

Too much load on the rpc server can lead to a bad user experience.

Or maybe you just want a single command to setup a local polkadot-rpc node and explorer instance?

Enter local-polkadot

Instead of

• start two terminals
• download or compile the latest polkadot exe and polkadot-js/apps
• run chmod +x polkadot
• run yarn install, yarn run start

You can just

local-polkadot # 😉 < -- without the emoji

Usage

Install it using cargo-install or compile it from source

cargo install local-polkadot

Run it however you want

# Without options
local-polkadot # uses $HOME/.local-polkadot as data directory

# With a path to download in a specific location
local-polkadot --path <PATH> 

# Re-download everything, removing the old 
local-polkadot --fresh
# Or if you want to use a specific path 
local-polkadot --fresh --path <PATH>

# Keeping things clean, by removing everything at the end of the process
local-polkadot --tmp

# Or create a tmp in a path of your choice
local-polkadot --tmp --path <PATH> # Creates a subfolder in PATH that gets removed at the end of the proces

## USE ctrl-c to gracefully shutdown

And that's it! Visit http://localhost:3000/?rpc=ws%3A%2F%2F127.0.0.1%3A9944#/explorer in your browser after warp-sync has finished.

Under the hood

local-polkadot by default creates a directory called .local-polkadot in your home ($HOME) and downloads the latest polkadot and polkadot-js/apps releases. It then starts them both: polkadot on port 9944 and apps on port 3000. Use ctrl-c to terminate and clean up.

If you find yourself using local-polkadot often you'd want to keep your downloaded software updated.

This is where you use --fresh

local-polkadot --fresh

Would remove the $HOME/.local-polkadot folder, recreate it, and redownload the latest polkadot and apps source code.

Without any volatile options like --fresh or --tmp, local-polkadot will use the prepared artifacts for faster startup. So most often using it without options or just a --path if you're using a custom path is what you'd want to do.

Use without polkadot-js

If you're already running an explorer or don't want to download it for some reason, you can pass in --skip-pjs or --skip-polkadotjs which only runs polkadot and nothing else.

More about local-polkadot

This tool does nothing new that couldn't be done manually. I created this for myself as I found myself doing these steps manually.

It specifically looks for files pjs.zip, apps-master and polkadot in its working directory, to decide if it needs to download or unzip apps-master archive again.

This tool works because warp sync a feature of polkadot and substrate built chains that allows it to quickly sync up with the main network by downloading finality proofs instead of whole blocks which would make this a tediously long exercise.

You must have yarn on your system if you want to use the explorer otherwise just use --skip-pjs.

Internally it does:

# For explorer
yarn install;
yarn run start;
# For Polkadot
polkadot --chain polkadot --sync warp --rpc-methods Safe --tmp --rpc-port 9944 --rpc-cors all ... # and a few more

To see what's new checkout the CHANGELOG