Interacting with your contract

Let's proceed to generating transactions and retrieving information from the contract we have deployed.

Querying

Queries read from the blockchain. They don't modify anything stored on chain, so they do not incur any gas fees.

There are several types of queries we can perform, but a common type that we are interested in is contract-state, which we will call in smart mode. This enables us to run queries with arguments, instead of dumping the entire contract data or metadata.

If we query the count before modifying any state, we get the value we set during instantiation:

archway contracts query smart CONTRACT [STDININPUT] [--json] [--log-level debug|error|info|warn] [--no-validation] [--args <value> | --args-file <value>| ]

A basic example for our increment contract would be:

archway contracts query smart increment --args '{"get_count": {}}'

Outputs:

{  "count": 0}

Why was the query argument {"get_count": {}}?

If we open src/contract.rs and inspect the function pub fn query, we will see the case matching statement that matches our JSON query:

pub fn query(deps: Deps, _env: Env, msg: QueryMsg) -> StdResult<Binary> {  match msg {      QueryMsg::GetCount {} => to_binary(&query_count(deps)?), // Here it is  }}

Transacting

To increment our counter value, we'll be executing a transaction that calls the function pub fn try_increment in src/contract.rs. This function is already public, but the transaction execution is handled by the function pub fn execute in src/contract.rs, which does pattern matching to call try_increment.

Sending an Increment transaction, using the archway CLI:

archway contracts execute increment --args '{"increment": {}}'

Sending an Increment transaction, using archwayd:

archwayd tx wasm execute --chain-id archway-1 archway188u72zstacfq4uknszr0cqry8vn68ynrcfcee4xjlmk6v2vhewysnkr798  '{"increment": {}}' --from my-wallet --node https://rpc.mainnet.archway.io:443 --gas auto --gas-prices $(archwayd q rewards estimate-fees 1 --node 'https://rpc.mainnet.archway.io:443' --output json | jq -r '.gas_unit_price | (.amount + .denom)') --gas-adjustment 1.3

archwayd tx wasm execute --chain-id constantine-3 archway188u72zstacfq4uknszr0cqry8vn68ynrcfcee4xjlmk6v2vhewysnkr798  '{"increment": {}}' --from my-wallet --node https://rpc.constantine.archway.io:443 --gas auto --gas-prices $(archwayd q rewards estimate-fees 1 --node 'https://rpc.constantine.archway.io:443' --output json | jq -r '.gas_unit_price | (.amount + .denom)') --gas-adjustment 1.3

Example output:

✔ Enter the name or address of the account that will send the transaction … mywalletExecuting contract increment2  Chain: constantine-3  Signer: mywallet✅ Executed contract  increment2-0.1.0  Transaction: CEFC1B9F6AE482249C3F6F3ED1C723F25FA8C129F53F5169544931207769311A

Why is the argument {"increment": {}}?

If we open src/contract.rs and inspect the pub fn execute function, we'll see a pattern matching statement that matches our JSON argument:

pub fn execute(  deps: DepsMut,  _env: Env,  info: MessageInfo,  msg: ExecuteMsg,) -> Result<Response, ContractError> {  match msg {    ExecuteMsg::Increment {} => try_increment(deps), // Here it is    ExecuteMsg::Reset { count } => try_reset(deps, info, count),  }}

As you can see, enum attributes again are converted. ExecuteMsg::Increment {} becomes {"increment": {}} in the CLI.

pub struct MessageInfo {  pub sender: Addr,  pub funds: Vec<Coin>,}

If our { "increment": {}} transaction succeeded and we query count again, it will have increased by 1*:

archway contracts query smart increment --args '{"get_count": {}}'

Now outputs:

{  "count": 1}