NEP 22: Contract Update Standard

nep-22.mediawiki

@@ -0,0 +1,71 @@
+<pre>
+  NEP: 22
+  Title: Contract Update Function
+  Author: Owen Zhang <[email protected]>, Fernando Díaz Toledano <[email protected]>, Erik Zhang <[email protected]>, Roman Khimov <[email protected]>
+  Type: Standard
+  Status: Accepted
+  Created: 2021-04-19
+</pre>
+
+
+==Abstract==
+
+This proposal outlines a standard for the NEO blockchain that will provide systems with a generalized interaction mechanism for smart contract update.
+
+==Motivation==
+
+As the Neo blockchain scales, Smart Contract Update will become increasingly important. We need a standard for <code>update</code> method in contract to callback native <code>ContractManagement</code> correctly.
+
+==Specification==
+
+All contracts SHOULD implement this NEP in case of any bug hotfix or improvement. If no update method there, incorrect action can never be corrected.
+
+===Methods===
+
+====update====
+
+<pre>
+{
+  "name": "update",
+  "safe": false,
+  "parameters": [
+    {
+      "name": "nefFile",
+      "type": "ByteArray"
+    },
+    {
+      "name": "manifest",
+      "type": "ByteArray"
+    },
+    {
+      "name": "data",
+      "type": "Any"
+    }
+  ],
+  "returntype": "Void"
+}
+</pre>
+
+This method MUST CALL <code>update</code> method in native <code>ContractManagement</code> contract. It will update contract state if it's executed successfully.
+
+Updating a smart contract MUST have <code>nefFile</code> or <code>manifest.json</code>. How do they work is in reference of [NEP-15](https://github.com/neo-project/proposals/blob/master/nep-15.mediawiki) and [NEP-16](https://github.com/neo-project/proposals/blob/master/nep-16.mediawiki). Just updating one of them at a time is OK. This means no change on another, so another SHOULD be set as null. It MUST be passed to ContractManagement.Update() in this method.
+
+The parameter <code>data</code> can be any type of supported parameters for contract-specific purpose. For [example](https://github.com/nspcc-dev/neofs-contract/blob/99fb86c35a48ed12017423aa4fee13f7d07fa4c0/contracts/proxy/contract.go#L33) some kinds of parameters can be put into data for specific check. Also some reference in [NEP-29](https://github.com/neo-project/proposals/blob/master/nep-29.mediawiki).
+
+This method SHOULD do <code>Checkwitness</code> for contract <code>owner</code> to avoid security risks. This function SHOULD use the SYSCALL <code>Neo.Runtime.CheckWitness</code> to verify the <code>signer</code>. 
+
+It's strongly recommended to execute all codes before calling ContractManagement.Update() to ensure they can be executed correctly.
+
+===References===
+
+https://github.com/neo-project/proposals/blob/master/nep-15.mediawiki
+
+https://github.com/neo-project/proposals/blob/master/nep-16.mediawiki
+
+https://github.com/neo-project/proposals/blob/master/nep-29.mediawiki
+
+===Implementation===
+
+* C#: https://github.com/neo-project/neo-devpack-dotnet/blob/003a50095efe88f63f518a0c989921be086409f3/examples/Example.SmartContract.NEP17/SampleNep17Token.cs#L130
+
+* Go: https://github.com/nspcc-dev/neofs-contract/blob/99fb86c35a48ed12017423aa4fee13f7d07fa4c0/contracts/proxy/contract.go#L33