XCM Workshop Setup Script

[bernardoaraujor]

Motivation

The XCM Workshop slide deck has been circulating a lot. It's been a great introductory resource for many people (DS & external) to learn the basics of XCM.

In the reserve-based transfer secion, the slides accumulate unnecessary complexity in the form of extra steps that are necessary to configure the chains before the XCM calls can be executed. For example, simply creating a sufficient asset (xUSD) on Statemine requires all these steps:

1. Creating the Asset
2. Minting xUSD
3. Reading chain-state (for dmpQueue/maxIndividual and asset/minBalance)
4. Sending a paraSudoWrapper of a forceCreate encoded call

Although still arguably a learning experience (however not necessarily XCM-related), all these steps introduce a lot of room for human error and confusion, especially for a less-experienced and naive audience.

Ideally, we should have some mechanism that not only launches the XCM Playground, but also bootstraps the chains with all the necessary conditions, abstracting away the non-XCM-related operations. Those can still be mentioned on the slides for awareness, but the human steps should focus on XCM calls only.

Suggested Solution

We need some helper utility that will:

• Create xUSD on Statemine
• Make xUSD sufficient on Statemine (this can be achieved in the same call that creates it)
• Mint xUSD on Statemine
• Create txUSD on Trappist
• Registers xUSD<>txUSD on AssetRegistry (or maybe not? this step might still be a good learning exercise to be done manually)
• Create pxUSD on parachain 3000

This helper utility can be based on one of the following:

• CAPI - TypeScript - Downside: introduces deno as extra dependency to the audience
• PolkadotJS API - JavaScript - Downside: introduces node/npm/yarn as extra dependency to the audience
• subxt - Rust - Upside: no extra dependencies to the audience

Then some shell script would orchestrate the launch of Zombienet and call the helper utility, making the playground ready for the audience to perform the XCM calls.

Alternatives

We also have the following alternatives:

• Simply using parachains-integration-tests. Downside is the introduction of yet another dependency for the audience to install locally, and the potential for confusion since that's not the main purpose for the tool.
• Using Zombienet's test functionality with JS calls. However that feels a bit like a hack, since we don't really want to test anything (we know the calls work), and showing test results on the Zombienet's logs might further confuse the audience.