The smart contract stores messages from users. Messages can be premium
if the user attaches sufficient money (0.1 $NEAR).
this.messages = [];
@call
// Public - Adds a new message.
add_message({ text }: { text: string }) {
// If the user attaches more than 0.1N the message is premium
const premium = near.attachedDeposit() >= BigInt(POINT_ONE);
const sender = near.predecessorAccountId();
const message = new PostedMessage({premium, sender, text});
this.messages.push(message);
}
@view
// Returns an array of messages.
get_messages({ fromIndex = 0, limit = 10 }: { fromIndex: number, limit: number }): PostedMessage[] {
return this.messages.slice(fromIndex, fromIndex + limit);
}
You can automatically compile and test the contract by running:
npm run test
You can create a testnet account and deploy the contract by running:
near create-account <your-account.testnet> --useFaucet
near deploy <your-account.testnet> build/release/hello_near.wasm
get_messages
is a read-only method (view
method) that returns a slice of the vector messages
.
View
methods can be called for free by anyone, even people without a NEAR account!
near view <your-account.testnet> get_messages '{"from_index":0, "limit":10}'
add_message
adds a message to the vector of messages
and marks it as premium if the user attached more than 0.1 NEAR
.
add_message
is a payable method for which can only be invoked using a NEAR account. The account needs to attach money and pay GAS for the transaction.
# Use near-cli to donate 1 NEAR
near call <your-account.testnet> add_message '{"text": "a message"}' --amount 0.1 --accountId <your-account.testnet>
Tip: If you would like to add a message another account, first login into NEAR using:
# Use near-cli to login your NEAR account
near login
and then use the logged account to sign the transaction: --accountId <your-account.testnet>
.