Migrate Contract

In this section we will describe the process up upgrading smart contracts.

Previously, some suggestions were made that would require smart contract code and state updates. To recap:

Change the allowed transfer fee percentage range.

Update the transfer fee percentage to a new value in a migrate message.

This was left as an exercise for the reader, so take some time here to update the smart contract code - remember to update and add more unit tests!

Hints

File: src/lib.rs

rust
#![warn(clippy::all)]
pub mod contract;
pub mod error;
pub mod msg;
pub mod state;

File: src/msg.rs

rust
/// Migrate the contract, setting a new fee percentage.
#[cw_serde]
pub struct MigrateMsg {
    pub new_fee_percent: Decimal,
}

File: src/contract.rs

rust
/// Called when migrating a contract instance to a new code ID.
pub fn migrate(_deps: DepsMut, _env: Env, _msg: MigrateMsg) -> Result<Response, ContractError> {
    // 1) Ensure the new fee percent is within the updated range.
    // 2) Get mutable ref to the contract state
    // 3) Set new fee percent in the state
    Ok(Response::default())
}

Suggested test stubs

rust
#[test]
fn valid_migrate() {
    // Test happy-path migrate here
    todo!()
}

#[test]
fn invalid_migrate() {
    // Test migrate error scenarios here
    todo!()
}

File: examples/schema.rs

rust
use cosmwasm_schema::write_api;
use name::msg::{ExecuteMsg, InitMsg, QueryMsg};

fn main() {
    write_api! {
        execute: ExecuteMsg,
        instantiate: InitMsg,
        migrate: MigrateMsg,
        query: QueryMsg,
    }
}

When complete, use the CLI commands below to migrate the smart contract instance to a new code ID.

Store

Since Wasm can't be updated or changed once deployed, the newly optimized Wasm file must be stored in provenance under a new code ID.

To store the new version, re-run the store command

shell
provenanced tx wasm store tutorial.wasm \\
    --instantiate-only-address $(provenanced keys show -a feebucket --keyring-backend test --home build/run/provenanced --testnet) \\
    --from feebucket \\
    --keyring-backend test \\
    --home build/run/provenanced \\
    --chain-id testing \\
    --gas auto \\
    --fees 25000nhash \\
    --broadcast-mode block \\
    --yes \\
    --testnet | jq

To query for both uploaded code entries

shell
provenanced q wasm list-code --testnet -o json | jq

Should output JSON similar to

json
{
  "code_infos": [
    {
      "code_id": "1",
      "creator": "tp102c9nplcvrxmhevc6wenm99q6dfte3k3z8vscv",
      "data_hash": "F2F2CD9AA2C192A95B86E9429BC15DCD6B8859BE54C8C66274B80347D2443D82",
    },
    {
      "code_id": "2",
      "creator": "tp102c9nplcvrxmhevc6wenm99q6dfte3k3z8vscv",
      "data_hash": "F2F2CD9AA2C192A95B86E9429BC15DCD6B8859BE54C8C66274B80347D2443D82",
    }
  ],
  "pagination": {
    "next_key": null,
    "total": "0"
  }
}

Copy the new code ID to migrate the current instance.

To query the contract address, query using the original code ID, 1

shell
provenanced q wasm list-contract-by-code 1 --testnet -o json | jq

Copy the contract address value from the output

json
{
  "contracts": [
    "tp18vd8fpwxzck93qlwghaj6arh4p7c5n89x8kskz"
  ],
  "pagination": {
    "next_key": null,
    "total": "0"
  }
}

Migrate

Now instead of instantiating a new instance, a separate migrate command can be run

shell
provenanced tx wasm migrate \\
    tp18vd8fpwxzck93qlwghaj6arh4p7c5n89x8kskz \\
    2 \\
    '{"new_fee_percent":"0.05"}' \\
    --from feebucket \\
    --keyring-backend test \\
    --home build/run/provenanced \\
    --chain-id testing \\
    --gas auto \\
    --fees 3500nhash \\
    --broadcast-mode block \\
    --yes \\
    --testnet | jq

The instance is now migrated to the updated Wasm code - with the updated fee range and percent.

To verify, query for contract instances under the new code ID

shell
provenanced q wasm list-contract-by-code 2 -o json | jq

Should output JSON similar to

json
{
  "contracts": [
    "tp18vd8fpwxzck93qlwghaj6arh4p7c5n89x8kskz"
  ],
  "pagination": {
    "next_key": null,
    "total": "0"
  }
}

To verify, query the state of the contract.

shell
provenanced query wasm contract-state smart \\
    tp18vd8fpwxzck93qlwghaj6arh4p7c5n89x8kskz '{"query_request":{}}' --testnet -o json | jq

Should reflect the updated fee percent.

json
{
  "data": {
    "purchase_denom": "purchasecoin",
    "merchant_address": "tp1jeqf9m9psa5jvurzpwtdk5m5429fhq48f0u5wq",
    "fee_collection_address": "tp102c9nplcvrxmhevc6wenm99q6dfte3k3z8vscv",
    "fee_percent": "0.05"
  }
}