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Simple Template

In this section

We will show you how to quickly deploy a sample template smart contract.

Create​

Clone and create the project form the git repository as shown below:

cargo generate --git https://github.com/CosmWasm/cw-template.git --branch 1.0-minimal --name PROJECT_NAME

Build​

Go to the project folder and build the project with Cargo.

cargo wasm

To compile a much smaller bytecode, you can use the following command which tells the compiler to strip the unused parts of the code:

RUSTFLAGS='-C link-arg=-s' cargo wasm

The compilation should output a .wasm file having the same name with project in the following folder: target/wasm32-unknown-unknown/release/.

PROJECT_NAME.wasm

Deploy​

Upload contract source code to chain​

The file we generated in the previous instruction is a wasm binary executable. To deploy, we need to upload the code to the blockchain. To do that you need to use a store transaction type. Once that is done you can download the bytecode and verify it.

Store the contract bytecode in the blockchain with the following command:

RES=$(wasmd tx wasm store target/wasm32-unknown-unknown/release/PROJECT_NAME.wasm --from wallet $TXFLAG -y --output json -b block)
  • wallet is your aurad wallet name you want to use to send the transaction.
  • PROJECT_NAME is the name you gave to the project.
tip

You can see the list of Codes that have been uploaded to the blockchain.

wasmd query wasm list-code $NOD

Display the response of the transaction:

echo $RES

The response contains a Code Id of the uploaded wasm binary. The following is an easier way to get the Code Id from the response:

CODE_ID=$(echo $RES | jq -r '.logs[0].events[-1].attributes[0].value')
echo $CODE_ID

Let's see the list of contracts instantiated using the Code Id above.

wasmd query wasm list-contract-by-code $CODE_ID $NODE --output json

The response should be an empty list as we have not instantiated any contract yet.

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

Before we instantiate a contract with the Code Id and interact with it, let us check if the code stored on the blockchain is indeed the PROJECT_NAME.wasm binary we uploaded.

# Download the wasm binary from the chain and compare it to the original one
wasmd query wasm code $CODE_ID $NODE download.wasm
# The two binaries should be identical
diff target/wasm32-unknown-unknown/release/PROJECT_NAME.wasm download.wasm

Instantiating the Contract​

We can now create an instance of the wasm contract. Following the instantiation, we can make queries and this time receive non-empty responses.

# Prepare the instantiation message
INIT='{"purchase_price":{"amount":"100","denom":"umlg"},"transfer_price":{"amount":"999","denom":"umlg"}}'

# Instantiate the contract
wasmd tx wasm instantiate $CODE_ID "$INIT" --from wallet --label "a project label" $TXFLAG -y --no-admin

# Check the contract details and account balance
wasmd query wasm list-contract-by-code $CODE_ID $NODE --output json
CONTRACT=$(wasmd query wasm list-contract-by-code $CODE_ID $NODE --output json | jq -r '.contracts[-1]')
echo $CONTRACT

# See the contract details
wasmd query wasm contract $CONTRACT $NODE
# Check the contract balance
wasmd query bank balances $CONTRACT $NODE

# Upon instantiation the cw_nameservice contract will store the instatiation message data in the contract's storage with the storage key "config".
# Query the entire contract state
wasmd query wasm contract-state all $CONTRACT $NODE