Stargaze Multi Snapshot

On EVM chains, Multicall is used to execute multiple contract queries at once, by using an on-chain contract to handle the querying. This reduces the number of RPC calls needed, and allows a much quicker response.

On the Stargaze side, it is very common to perform snapshot of collection holders. In cases of the average collection size, this would ultimately result in thousands of RPC calls.

This contract allows passing in the address of a SG721 NFT contract, the start and end index and having the contract perform the lookups. We can then return multiple responses per RPC call, greatly reducing the hammering on validator endpoints, as well as speeding up the process.

Also included in the Tester folder is a simple nodejs script that uses the cosmwasm library to call this function, providing a testnet NFT collection.


Code ID: 429

Testnet Address: stars1nhyua3khswcu8zcz24n4kc6aasxsn3myqlhtxakelqkahv6txzeq8r6gk8

Example Response (Start:30, End: 35):


[

{ id: 30, owner: 'stars17y9ysn4uwusc0qv0d48wtc5rf4gnu6mqvjpvg9' },

{ id: 31, owner: 'stars17y9ysn4uwusc0qv0d48wtc5rf4gnu6mqvjpvg9' },

{ id: 32, owner: 'stars17y9ysn4uwusc0qv0d48wtc5rf4gnu6mqvjpvg9' },

{ id: 33, owner: 'stars17y9ysn4uwusc0qv0d48wtc5rf4gnu6mqvjpvg9' },

{ id: 34, owner: 'stars17y9ysn4uwusc0qv0d48wtc5rf4gnu6mqvjpvg9' },

{ id: 35, owner: 'stars17y9ysn4uwusc0qv0d48wtc5rf4gnu6mqvjpvg9' }

]

Testing instructions

Compilation

First, we must build our wasm binary to store on the blockchain.

This is done using the rust-optimizer Docker container. (macOS arm64 see this image)

# x86_64

cargo optimize

  

# arm64

cargo optimize-arm64

Code Storage

After the wasm has compiled, we can upload the binary to the blockchain. This is done with the cargo script shown below. This cargo script assumes the developer's keys are stored in the os backend and named dev.

Note: the Stargaze CLI is required for this step.

cargo store

Look in the command output for the code_id field. This value will be needed in the next step.

{"type":"store_code","attributes":[{"key":"code_id","value":"338"}]}]}]

Contract Instantiation

Once our code has been stored on the blockchain, we can instantiate a version of this code as our MultiSnapshot contract. This is done using the following command:

starsd tx wasm instantiate [CODE_ID] "{}" --label "Multi Snapshot Test" --admin [ADMIN ADDRESS] --gas-prices 0.025ustars --gas auto --gas-adjustment 1.9 --from [KEY NAME] -b block

Make sure to replace to placeholders ([CODE ID], [ADMIN ADDRESS], [KEY NAME]) with your relevant values. [CODE ID] should be the value you found in the Code Storage section.

Client Tests

Finally we can test the code. Use the commands below to get started. They should be run from the project root.

# Install dependencies

cargo prep-client

  

# Run the AllCollectionOwners query on the front end

cargo client-all

  

# Run the CollectionOwnersRange query on the front end

cargo client-range

Parameter Tuning

The optimal performance of the contract will be determined by the two tunable parameters inside querytest.js. We use iters to perform multiple batch queries in a single RPC request. cw721 has a maximum value of 100 for the limit parameter used in the AllTokens query, which requires us to maximize the gas limits with the iters param. These parameters can be tuned at the top of /Tester/querytest.js.

Running Modes

The contract has two functions, all_collection_owners and collection_owners_range.

all_collection_owners: For rapidly snapshotting the entire collection, in no particular order. (Based on the response of the all_tokens query).

Arguments:

collection - The SG721 contract address to snapshot
iters - The number of cycle runs. (Optional)
limit: Number of requests per iter (Optional)
start_after: The starting token id for the initial iteration (Optional)

With only providing the one required parameter, the default options will return 20 results. In testing performed on testnet, we were able to get up to 400 results returned before maxing out gas, using 10 iters and a limit of 40.

collection_owners_range: For snapshotting by a certain range. In some cases you may only need to return a ranged subset of a collection.