Calling your contract

Now that your contract is deployed locally, we can start interacting with it.

Grab the contract address that was outputted from the previous step.

pop call contract -p ./flipper --contract 5CLPm1CeUvJhZ8GCDZCR7nWZ2m3XXe4X5MtAQK69zEjut36A --message get --suri //Alice

If you lost the address, you can always pull up PolkadotJs Apps and check the chain state for the contract address.

┌   Pop CLI : Calling a contract
│
◐  Calling the contract...                                                                                                                   
⚙  Result: Ok(false)
│  
▲  Your call has not been executed.
│  
▲  To submit the transaction and execute the call on chain, add -x/--execute flag to the command.
│  
└  Call completed successfully!

The result here is false meaning that value in the contract storage is set to false.

Let's try flipping it. Remember to update the contract address accordingly.

pop call contract -p ./flipper --contract 5CLPm1CeUvJhZ8GCDZCR7nWZ2m3XXe4X5MtAQK69zEjut36A --message flip --suri //Alice -x

Gas Estimate

Notice the -x flag at the end of the pop call command. This is needed because we are executing a transaction on the network, and it will cost gas.

Typically it is useful for you to estimate how much gas the call will cost. Fortunately you can do this with the --dry-run flag:

pop call contract -p ./flipper --contract 5CLPm1CeUvJhZ8GCDZCR7nWZ2m3XXe4X5MtAQK69zEjut36A --message flip --suri //Alice -x --dry-run

┌   Pop CLI : Calling a contract
│
◐  Doing a dry run to estimate the gas...                                                                                                    
⚙  Gas limit Weight { ref_time: 382198493, proof_size: 18636 }
│  
◓  Calling the contract...                                                                                                                   
⚙        Events
│         Event Balances ➜ Withdraw
│           who: 5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY
│           amount: 1.550397502mUNIT
│         Event Contracts ➜ Called
│           caller: Signed(5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY)
│           contract: 5CLPm1CeUvJhZ8GCDZCR7nWZ2m3XXe4X5MtAQK69zEjut36A
│         Event TransactionPayment ➜ TransactionFeePaid
│           who: 5GrwvaEF5zXb26Fz9rcQpDWS57CtERHpNehXCPcNoHGKutQY
│           actual_fee: 1.550397502mUNIT
│           tip: 0UNIT
│         Event System ➜ ExtrinsicSuccess
│           dispatch_info: DispatchInfo { weight: Weight { ref_time: 1302708493, proof_size: 9064 }, class: Normal, pays_fee: Yes }
│  
└  Call completed successfully!

Did it work? See if the value has been flipped by calling the contract again. Remember to update the contract address accordingly.

pop call contract -p ./flipper --contract 5CLPm1CeUvJhZ8GCDZCR7nWZ2m3XXe4X5MtAQK69zEjut36A --message get --suri //Alice

┌   Pop CLI : Calling a contract
│
◐  Calling the contract...                                                                                                          
⚙  Result: Ok(true)
│  
▲  Your call has not been executed.
│  
▲  To submit the transaction and execute the call on chain, add -x/--execute flag to the command.
│  
└  Call completed successfully!

The value is now true.

Awesome, you now know how to make calls to your smart contract.

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