SRC14 add proxy_target() (#110)

* Add proxy_target() to standard

* Add proxy_target to SRC14 abi

* Add proxy_target() to examples

* Update CHANGELOG with SRC14 add proxy_target() PR

CHANGELOG.md

@@ -12,6 +12,7 @@ Description of the upcoming release here.
 ### Added
 
 - [#107](https://github.com/FuelLabs/sway-standards/pull/107) Adds the `proxy_owner()` function to the SRC-14 standard.
+- [#110](https://github.com/FuelLabs/sway-standards/pull/110) Adds the `proxy_target()` function to the SRC-14 standard.
 - Something new here 2
 
 ### Changed
@@ -25,5 +26,13 @@ Description of the upcoming release here.
 
 #### Breaking
 
-- Some breaking change here 1
-- Some breaking change here 2
+- [#110](https://github.com/FuelLabs/sway-standards/pull/110) Breaks the `SRC14` abi by adding the `proxy_target()` function. This will need to be added to any SRC14 implementation. The new abi is as follows:
+
+```sway
+abi SRC14 {
+    #[storage(read, write)]
+    fn set_proxy_target(new_target: ContractId);
+    #[storage(read)]
+    fn proxy_target() -> Option<ContractId>;
+}
+```

docs/src/src-14-simple-upgradeable-proxies.md

@@ -38,9 +38,13 @@ The following functions MUST be implemented by a proxy contract to follow the SR
 
 #### `fn set_proxy_target(new_target: ContractId);`
 
-If a valid call is made to this function it MUST change the target address of the proxy to `new_target`.
+If a valid call is made to this function it MUST change the target contract of the proxy to `new_target`.
 This method SHOULD implement access controls such that the target can only be changed by a user that possesses the right permissions (typically the proxy owner).
 
+#### `fn proxy_target() -> Option<ContractId>;`
+
+This function MUST return the target contract of the proxy as `Some`. If no proxy is set then `None` MUST be returned.
+
 ### Optional Public Functions
 
 The following functions are RECOMMENDED to be implemented by a proxy contract to follow the SRC-14 standard:
@@ -73,6 +77,8 @@ Use of the [SRC-5; Ownership Standard](./src-5-ownership.md) is discouraged. If
 abi SRC14 {
     #[storage(read, write)]
     fn set_proxy_target(new_target: ContractId);
+    #[storage(read)]
+    fn proxy_target() -> Option<ContractId>;
 }
 
 abi SRC14Extension {

examples/src14-simple-proxy/minimal/src/minimal.sw

@@ -15,6 +15,11 @@ impl SRC14 for Contract {
     fn set_proxy_target(new_target: ContractId) {
         storage.target.write(new_target);
     }
+
+    #[storage(read)]
+    fn proxy_target() -> Option<ContractId> {
+        storage.target.try_read()
+    }
 }
 
 #[fallback]

examples/src14-simple-proxy/owned/src/owned.sw

@@ -21,6 +21,11 @@ impl SRC14 for Contract {
         only_owner();
         storage.target.write(new_target);
     }
+
+    #[storage(read)]
+    fn proxy_target() -> Option<ContractId> {
+        storage.target.try_read()
+    }
 }
 
 impl SRC14Extension for Contract {

standards/src/src14.sw

@@ -3,7 +3,7 @@ library;
 use ::src5::State;
 
 abi SRC14 {
-    /// Change the target address of a proxy contract.
+    /// Change the target contract of a proxy contract.
     ///
     /// # Arguments
     ///
@@ -22,6 +22,25 @@ abi SRC14 {
     /// ```
     #[storage(read, write)]
     fn set_proxy_target(new_target: ContractId);
+
+    /// Returns the target contract of a proxy contract.
+    ///
+    /// # Returns
+    ///
+    /// * [Option<ContractId>] - The new proxy contract to which all fallback calls will be passed or `None`.
+    ///
+    /// # Examples
+    ///
+    /// ```sway
+    /// use src14::SRC14;
+    ///
+    /// fn foo(contract_id: ContractId) {
+    ///     let contract_abi = abi(SRC14, contract_id.bits());
+    ///     let target_contract: Option<ContractId> = contract_abi.proxy_target();
+    /// }
+    /// ```
+    #[storage(read)]
+    fn proxy_target() -> Option<ContractId>;
 }
 
 abi SRC14Extension {