feat(rln)!: generate contract types, migrate from ethers to viem

[adklempner]

Problem / Description

Previous to this, the ABIs for the contracts were manually added to the rln package (not clear how).
Additionally, code related to calling the contracts was not typed, so any breaking changes to the ABI would not be detected at compile time.

Solution

• Create a script that:

1. cloneshttps://github.com/waku-org/waku-rlnv2-contract
2. compiles it
3. uses the output to generate typesafe ABI code using wagmi

The rest of the code has been updated to use viem, which provides clean and typesafe ways to interact with the smart contracts.

Also adds new methods that were introduced in latest contract changes, specifically the ability to query for merkle root and merkle proof for a commitment directly from the smart contract.

Notes

• Resolves feat(rln): replace manual smart contract classes/functions with generate typings #2630
• Dogfooding PR: feat: use viem instead of ethers rln.waku.org#20

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Checklist

• Code changes are covered by unit tests.
• Code changes are covered by e2e tests, if applicable.
• Dogfooding has been performed, if feasible.
• A test version has been published, if required.
• All CI checks pass successfully.

[github-actions]

size-limit report 📦

Path	Size	Loading time (3g)	Running time (snapdragon)	Total time
Waku node	96.24 KB (0%)	2 s (0%)	1.1 s (+76.4% 🔺)	3 s
Waku Simple Light Node	147.6 KB (0%)	3 s (0%)	705 ms (-3.76% 🔽)	3.7 s
ECIES encryption	22.62 KB (0%)	453 ms (0%)	287 ms (+26.15% 🔺)	739 ms
Symmetric encryption	22 KB (0%)	440 ms (0%)	236 ms (+28.06% 🔺)	676 ms
DNS discovery	52.17 KB (0%)	1.1 s (0%)	494 ms (+65.58% 🔺)	1.6 s
Peer Exchange discovery	52.91 KB (0%)	1.1 s (0%)	372 ms (-29.51% 🔽)	1.5 s
Peer Cache Discovery	46.64 KB (0%)	933 ms (0%)	394 ms (-23.68% 🔽)	1.4 s
Privacy preserving protocols	77.31 KB (0%)	1.6 s (0%)	627 ms (+35.87% 🔺)	2.2 s
Waku Filter	79.82 KB (0%)	1.6 s (0%)	714 ms (-1.34% 🔽)	2.4 s
Waku LightPush	77.97 KB (0%)	1.6 s (0%)	859 ms (+102.61% 🔺)	2.5 s
History retrieval protocols	83.74 KB (0%)	1.7 s (0%)	485 ms (-5% 🔽)	2.2 s
Deterministic Message Hashing	28.98 KB (0%)	580 ms (0%)	227 ms (-5.29% 🔽)	807 ms

[Copilot]

Pull Request Overview

This PR migrates the RLN package from ethers.js to viem for Ethereum interactions and introduces automated contract type generation using wagmi CLI. The changes enable type-safe contract interactions by generating TypeScript bindings directly from the smart contract ABIs.

Key changes:

• Replaced ethers.js with viem for all blockchain interactions
• Automated ABI generation via wagmi CLI from waku-rlnv2-contract repository
• Updated all contract interaction code to use viem's type-safe APIs
• Added new methods for querying merkle root and merkle proof directly from contracts

Reviewed Changes

Copilot reviewed 21 out of 23 changed files in this pull request and generated 8 comments.

Show a summary per file

File	Description
packages/rln/wagmi.config.ts	Configures wagmi CLI to generate TypeScript bindings from Foundry contracts
packages/rln/src/contract/wagmi/generated.ts	Auto-generated type-safe contract ABIs (977 lines)
packages/rln/src/contract/rln_base_contract.ts	Migrated from ethers Contract to viem getContract with type-safe reads/writes
packages/rln/src/utils/walletClient.ts	New utility to create viem client from window.ethereum
packages/rln/src/types.ts	Updated to use viem WalletClient instead of ethers.Signer
packages/rln/generate_contract_abi.sh	Shell script to clone, build, and generate contract types
packages/rln/package.json	Removed ethers dependency, added viem and wagmi tooling

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[Copilot]

Pull Request Overview

Copilot reviewed 21 out of 23 changed files in this pull request and generated 4 comments.

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[weboko]

good first iteration

left comments in addition to Copilot's

and make sure you properly integrate it with release CI

[Copilot]

Pull Request Overview

Copilot reviewed 21 out of 23 changed files in this pull request and generated 5 comments.

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[Copilot]

Pull request overview

Copilot reviewed 23 out of 25 changed files in this pull request and generated 7 comments.

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