feat: allow multiple operators

src/config/component.cairo

@@ -5,6 +5,8 @@
 /// Errors.
 mod errors {
     const INVALID_CALLER: felt252 = 'Config: not owner or operator';
+    const ALREADY_REGISTERED: felt252 = 'Config: already operator';
+    const NOT_OPERATOR: felt252 = 'Config: not operator';
 }
 
 /// Configuration component.
@@ -23,9 +25,8 @@ mod config_cpt {
 
     #[storage]
     struct Storage {
-        /// Appchain operator that is allowed to update the state.
-        // TODO(#9): Multiple Operators
-        operator: ContractAddress,
+        /// Appchain operators that are allowed to update the state.
+        operators: LegacyMap<ContractAddress, bool>,
         /// Program info (StarknetOS), with program hash and config hash.
         program_info: (felt252, felt252),
         /// Facts registry contract address.
@@ -38,13 +39,20 @@ mod config_cpt {
         +HasComponent<TContractState>,
         impl Ownable: ownable_cpt::HasComponent<TContractState>
     > of IConfig<ComponentState<TContractState>> {
-        fn set_operator(ref self: ComponentState<TContractState>, address: ContractAddress) {
+        fn register_operator(ref self: ComponentState<TContractState>, address: ContractAddress) {
             get_dep_component!(@self, Ownable).assert_only_owner();
-            self.operator.write(address)
+            assert(!self.operators.read(address), errors::ALREADY_REGISTERED);
+            self.operators.write(address, true);
         }
 
-        fn get_operator(self: @ComponentState<TContractState>) -> ContractAddress {
-            self.operator.read()
+        fn unregister_operator(ref self: ComponentState<TContractState>, address: ContractAddress) {
+            get_dep_component!(@self, Ownable).assert_only_owner();
+            assert(self.operators.read(address), errors::NOT_OPERATOR);
+            self.operators.write(address, false);
+        }
+
+        fn is_operator(self: @ComponentState<TContractState>, address: ContractAddress) -> bool {
+            self.operators.read(address)
         }
 
         fn set_program_info(
@@ -93,7 +101,7 @@ mod config_cpt {
             ref self: ComponentState<TContractState>, address: ContractAddress
         ) -> bool {
             let owner = get_dep_component!(@self, Ownable).owner();
-            address == owner || address == self.operator.read()
+            address == owner || self.is_operator(address)
         }
     }
 }

src/config/interface.cairo

@@ -5,19 +5,28 @@ use starknet::ContractAddress;
 
 #[starknet::interface]
 trait IConfig<T> {
-    /// Sets the operator that is in charge to push state updates.
+    /// Registers an operator that is in charge to push state updates.
+    /// Multiple operators can be registered.
+    /// # Arguments
     ///
+    /// * `address` - The account address to register as an operator.
+    fn register_operator(ref self: T, address: ContractAddress);
+
+    /// Unregisters an operator.
     /// # Arguments
     ///
-    /// * `address` - The operator account address.
-    fn set_operator(ref self: T, address: ContractAddress);
+    /// * `address` - The operator account address to unregister.
+    fn unregister_operator(ref self: T, address: ContractAddress);
 
-    /// Gets the operator address.
+    /// Verifies if the given address is an operator.
+    /// # Arguments
+    ///
+    /// * `address` - The address to verify.
     ///
     /// # Returns
     ///
-    /// The operator's address.
-    fn get_operator(self: @T) -> ContractAddress;
+    /// True if the address is an operator, false otherwise.
+    fn is_operator(self: @T, address: ContractAddress) -> bool;
 
     /// Sets the information of the program that generates the
     /// state transition trace (namely StarknetOS).

src/config/tests/test_config.cairo

@@ -15,24 +15,70 @@ fn deploy_mock() -> IConfigDispatcher {
 }
 
 #[test]
-fn config_set_operator_ok() {
+fn config_register_operator_ok() {
     let mock = deploy_mock();
-    assert(mock.get_operator() == c::ZERO(), 'expect 0 addr');
+    assert(!mock.is_operator(c::OPERATOR()), 'expect not operator');
 
     snf::start_prank(CheatTarget::One(mock.contract_address), c::OWNER());
 
-    mock.set_operator(c::OPERATOR());
-    assert(mock.get_operator() == c::OPERATOR(), 'expect operator');
+    mock.register_operator(c::OPERATOR());
+    assert(mock.is_operator(c::OPERATOR()), 'expect operator');
+}
+
+#[test]
+fn config_register_multiple_operators_ok() {
+    let mock = deploy_mock();
+    assert(!mock.is_operator(c::OPERATOR()), 'expect not operator');
+    assert(!mock.is_operator(c::OTHER()), 'expect not operator');
+
+    snf::start_prank(CheatTarget::One(mock.contract_address), c::OWNER());
+
+    mock.register_operator(c::OPERATOR());
+    mock.register_operator(c::OTHER());
+
+    assert(mock.is_operator(c::OPERATOR()), 'expect operator');
+    assert(mock.is_operator(c::OTHER()), 'expect operator');
+}
+
+#[test]
+fn config_unregister_operator_ok() {
+    let mock = deploy_mock();
+
+    snf::start_prank(CheatTarget::One(mock.contract_address), c::OWNER());
+
+    mock.register_operator(c::OPERATOR());
+    assert(mock.is_operator(c::OPERATOR()), 'expect operator');
+
+    mock.unregister_operator(c::OPERATOR());
+    assert(!mock.is_operator(c::OPERATOR()), 'expect not operator');
+}
+
+#[test]
+fn config_unregister_multiple_operators_ok() {
+    let mock = deploy_mock();
+
+    snf::start_prank(CheatTarget::One(mock.contract_address), c::OWNER());
+
+    mock.register_operator(c::OPERATOR());
+    mock.register_operator(c::OTHER());
+
+    assert(mock.is_operator(c::OPERATOR()), 'expect operator');
+    assert(mock.is_operator(c::OTHER()), 'expect operator');
+
+    mock.unregister_operator(c::OPERATOR());
+    mock.unregister_operator(c::OTHER());
+    assert(!mock.is_operator(c::OPERATOR()), 'expect not operator');
+    assert(!mock.is_operator(c::OTHER()), 'expect not operator');
 }
 
 #[test]
 #[should_panic(expected: ('Caller is not the owner',))]
 fn config_set_operator_unauthorized() {
     let mock = deploy_mock();
-    assert(mock.get_operator() == c::ZERO(), 'expect 0 addr');
+    assert(!mock.is_operator(c::OPERATOR()), 'expect 0 addr');
 
-    mock.set_operator(c::OPERATOR());
-    assert(mock.get_operator() == c::OPERATOR(), 'expect operator');
+    mock.register_operator(c::OPERATOR());
+    assert(mock.is_operator(c::OPERATOR()), 'expect operator');
 }
 
 #[test]
@@ -45,7 +91,7 @@ fn config_set_program_info_ok() {
     mock.set_program_info(0x1, 0x2);
     assert(mock.get_program_info() == (0x1, 0x2), 'expect correct hashes');
 
-    mock.set_operator(c::OPERATOR());
+    mock.register_operator(c::OPERATOR());
 
     // Operator can also set the program info.
     snf::start_prank(CheatTarget::One(mock.contract_address), c::OPERATOR());
@@ -75,7 +121,7 @@ fn config_set_facts_registry_ok() {
     mock.set_facts_registry(facts_registry_address);
     assert(mock.get_facts_registry() == facts_registry_address, 'expect valid address');
 
-    mock.set_operator(c::OPERATOR());
+    mock.register_operator(c::OPERATOR());
 
     // Operator can also set the program info.
     snf::start_prank(CheatTarget::One(mock.contract_address), c::OPERATOR());