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Access control

This page lists common examples of working with privileges, ownership and access control.

How to check sender privileges using Ownable trait

// Ownable has to be imported from stdlib, as well as Deployable, for convenience:
import "@stdlib/ownable";
import "@stdlib/deploy";


message FooBarMsg {
    newVal: Int as uint32;
}


// Ownable trait can limit certain actions to the owner only
contract SenderChecker with Deployable, Ownable {
    // Persistent state variables
    owner: Address;     // Ownable trait requires you to add this exact state variable
    val: Int as uint32; // some value


    init() {
        // we can initialize owner to any value we want, the deployer in this case:
        self.owner = sender();
        self.val = 0;
    }


    receive("inc") {
        self.requireOwner(); // throws exit code 132 if the sender isn't an owner
        self.val += 1;
    }


    receive(msg: FooBarMsg) {
        self.requireOwner(); // throws exit code 132 if the sender isn't an owner
        self.val = msg.newVal;
    }
}
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