CosmWasm Plus

Specification	Crates.io	Docs
cw0
cw1
cw2
cw3
cw4
cw20
cw1155

Utilities	Crates.io	Docs
cw-controllers
cw-multi-test
cw-storage-plus

Contracts	Download	Docs
cw1-subkeys	Release v0.10.1
cw1-whitelist	Release v0.10.1
cw3-fixed-multisig	Release v0.10.1
cw3-flex-multisig	Release v0.10.1
cw4-group	Release v0.10.1
cw4-stake	Release v0.10.1
cw20-atomic-swap	Release v0.10.1
cw20-base	Release v0.10.1
cw20-bonding	Release v0.10.1
cw20-escrow	Release v0.10.1
cw20-ics20	Release v0.10.1
cw20-staking	Release v0.10.1
cw20-merkle-airdrop	Release v0.10.1
cw1155-base	Release v0.10.1

Note that cw721 and cw721-base have moved to the new cw-nfts repo and can be followed there.

This is a collection of specification and contracts designed for use on real networks. They are designed not just as examples, but to solve real-world use cases, and to provide a reusable basis to build many custom contracts.

If you don't know what CosmWasm is, please check out our homepage and our documentation to get more background. We are running a public testnet you can use to test out any contracts.

Warning None of these contracts have been audited and no liability is assumed for the use of this code. They are provided to turbo-start your projects.

Note All code in pre-1.0 packages is in "draft" form, meaning it may undergo minor changes and additions until 1.0. For example between 0.1 and 0.2 we adjusted the Expiration type to make the JSON representation cleaner (before: expires: {at_height: {height: 12345}} after expires: {at_height: 12345})

Specifications

The most reusable components are the various cwXYZ specifications under packages. Each one defines a standard interface for different domains, e.g. cw20 for fungible tokens, cw721 for non-fungible tokens, cw1 for "proxy contracts", etc. The interface comes with a human description in the READMEs, as well as Rust types that can be imported.

They contain no logic, but specify an interface. It shows what you need to implement to create a compatible contracts, as well as what interface we guarantee to any consumer of such contracts. This is the real bonus of specifications, we can create an escrow contract that can handle many different fungible tokens, as long as they all adhere to the cw20 specification.

If you have ideas for new specifications or want to make enhancements to existing spec, please raise an issue or create a pull request on this repo.

Contracts

We provide sample contracts that either implement or consume these specifications to both provide examples, and provide a basis for code you can extend for more custom contacts, without worrying about reinventing the wheel each time. For example cw20-base is a basic implementation of a cw20 compatible contract that can be imported in any custom contract you want to build on it.

CW1 Proxy Contracts:

• cw1-whitelist a minimal implementation of cw1 mainly designed for reference.
• cw1-subkeys a simple, but useful implementation, which lets us use a proxy contract to provide "allowances" for native tokens without modifying the bank module.

CW3 Multisig:

• cw3-fixed-multisig a simple implementation of the cw3 spec. It is a multisig with a fixed set of addresses, created upon initialization. Each address may have the same weight (K of N), or some may have extra voting power. This works much like the native Cosmos SDK multisig, except that rather than aggregating the signatures off chain and submitting the final result, we aggregate the approvals on-chain.
• cw3-flex-multisig builds on cw3-fixed-multisig, with a more powerful implementation of the cw3 spec. It's a multisig contract backed by a cw4 (group) contract, which independently maintains the voter set.

CW4 Group:

• cw4-group a basic implementation of the cw4 spec. It handles elected membership, by admin or multisig. It fulfills all elements of the spec, including raw query lookups, and is designed to be used as a backing storage for cw3 compliant contracts.
• cw4-stake a second implementation of the cw4 spec. It fulfills all elements of the spec, including raw query lookups, and is designed to be used as a backing storage for cw3 compliant contracts. It provides a similar API to [cw4-group], but rather than appointing members, their membership and weight are based on the number of staked tokens they have.

CW20 Fungible Tokens:

• cw20-base a straightforward, but complete implementation of the cw20 spec along with all extensions. Can be deployed as-is, or imported by other contracts.

• cw20-atomic-swap an implementation of atomic swaps for both native and cw20 tokens.

• cw20-bonding a smart contract implementing arbitrary bonding curves, which can use native and cw20 tokens as reserve tokens.

• cw20-staking provides staking derivatives, staking native tokens on your behalf and minting cw20 tokens that can be used to claim them. It uses cw20-base for all the cw20 logic and only implements the interactions with the staking module and accounting for prices.

• cw20-escrow is a basic escrow contract (arbiter can release or refund tokens) that is compatible with all native and cw20 tokens. This is a good example to show how to interact with cw20 tokens.

• cw20-merkle-airdrop is a contract for efficient cw20 token airdrop distribution.

Compiling

To compile all the contracts, run the following in the repo root:

docker run --rm -v "$(pwd)":/code \
  --mount type=volume,source="$(basename "$(pwd)")_cache",target=/code/target \
  --mount type=volume,source=registry_cache,target=/usr/local/cargo/registry \
  cosmwasm/workspace-optimizer:0.12.3

This will compile all packages in the contracts directory and output the stripped and optimized wasm code under the artifacts directory as output, along with a checksums.txt file.

If you hit any issues there and want to debug, you can try to run the following in each contract dir: RUSTFLAGS="-C link-arg=-s" cargo build --release --target=wasm32-unknown-unknown --locked

Quality Control

One of the basic metrics of assurance over code quality is how much is covered by unit tests. There are several tools available for Rust to do such analysis and we will describe one below. This should be used as a baseline metric to give some confidence in the code.

Beyond code coverage metrics, just having a robust PR review process with a few more trained eyes looking for bugs is very helpful in detecting paths the original coder was not aware of. This is more subjective, but looking at the relevant PRs and depth of discussion can give an idea how much review was present.

After that, fuzzing it (ideally with an intelligent fuzzer that understands the domain) can be valuable. And beyond that formal verification can provide even more assurance (but is very time consuming and expensive).

Code Coverage

I recommend the use of tarpaulin: cargo install cargo-tarpaulin

To get some nice interactive charts, you can go to the root directory and run:

cargo tarpaulin -o html and then xdg-open tarpaulin-report.html (or just open on MacOS).

Once you find a package that you want to improve, you can do the following to just analyze this package, which gives much faster turn-around:

cargo tarpaulin -o html --packages cw3-fixed-multisig

Note that it will produce a code coverage report for the entire project, but only the coverage in that package is the real value. If does give quick feedback for you if you unit test writing was successful.

Generating changelog

To generate a changelog we decided to use github-changelog-generator.

To install tool you need Ruby's gem package manager.

$ gem --user install github_changelog_generator

And put $HOME/.gem/ruby/*/bin/ into your PATH.

Generating changelog file first time:

$ github_changelog_generator -u CosmWasm -p cw-plus

Appending next releases could be done adding --base flag:

$ github_changelog_generator -u CosmWasm -p cw-plus --base CHANGELOG.md

If you hit GitHub's 50 requests/hour limit, please follow this guide to create a token key which you can pass using --token flag.

There's also a convenience scripts/update_changelog.sh, which can take a --since-tag parameter (to avoid processing the entire history). It can also auto-detect the latest version tag for you, with --latest-tag.

Licenses

This repo contains two license, Apache 2.0 and AGPL 3.0. All crates in this repo may be licensed as one or the other. Please check the NOTICE in each crate or the relevant Cargo.toml file for clarity.

All specifications will always be Apache-2.0. All contracts that are meant to be building blocks will also be Apache-2.0. This is along the lines of Open Zepellin or other public references.

Contracts that are "ready to deploy" may be licensed under AGPL 3.0 to encourage anyone using them to contribute back any improvements they make. This is common practice for actual projects running on Ethereum, like Uniswap or Maker DAO.