taprpc: add tapscript sibling to finalize call

Author: jharveyb

rpcserver.go

@@ -1097,7 +1097,8 @@ func (r *rpcServer) NewAddr(ctx context.Context,
 		return nil, err
 	}
 
-	// Was there a tapscript sibling preimage specified?
+	// Was there a tapscript sibling preimage specified? If so, decode it
+	// and check that it is not a Taproot Asset Commitment.
 	tapscriptSibling, _, err := commitment.MaybeDecodeTapscriptPreimage(
 		req.TapscriptSibling,
 	)

taprpc/mintrpc/mint.pb.go

@@ -177,6 +177,22 @@ message FinalizeBatchRequest {
 
     // The optional fee rate to use for the minting transaction, in sat/kw.
     uint32 fee_rate = 2;
+
+    /*
+    The optional tapscript sibling that will be used when deriving the genesis
+    output for the batch. This sibling is a tapscript tree, which allows the
+    minter to encumber future transfers of assets in the batch with Tapscript.
+    */
+    oneof batch_sibling {
+        /*
+        An ordered list of TapLeafs, which will be used to construct a
+        Tapscript tree.
+        */
+        taprpc.TapscriptFullTree full_tree = 3;
+
+        // A TapBranch that represents a Tapscript tree managed externally.
+        taprpc.TapBranch branch = 4;
+    }
 }
 
 message FinalizeBatchResponse {

taprpc/mintrpc/mint.proto

@@ -196,6 +196,14 @@
           "type": "integer",
           "format": "int64",
           "description": "The optional fee rate to use for the minting transaction, in sat/kw."
+        },
+        "full_tree": {
+          "$ref": "#/definitions/taprpcTapscriptFullTree",
+          "description": "An ordered list of TapLeafs, which will be used to construct a\nTapscript tree."
+        },
+        "branch": {
+          "$ref": "#/definitions/taprpcTapBranch",
+          "description": "A TapBranch that represents a Tapscript tree managed externally."
         }
       }
     },
@@ -423,6 +431,43 @@
       ],
       "default": "ASSET_VERSION_V0",
       "description": " - ASSET_VERSION_V0: ASSET_VERSION_V0 is the default asset version. This version will include\nthe witness vector in the leaf for a tap commitment.\n - ASSET_VERSION_V1: ASSET_VERSION_V1 is the asset version that leaves out the witness vector\nfrom the MS-SMT leaf encoding."
+    },
+    "taprpcTapBranch": {
+      "type": "object",
+      "properties": {
+        "left_taphash": {
+          "type": "string",
+          "format": "byte",
+          "description": "The TapHash of the left child of the root hash of a Tapscript tree."
+        },
+        "right_taphash": {
+          "type": "string",
+          "format": "byte",
+          "description": "The TapHash of the right child of the root hash of a Tapscript tree."
+        }
+      }
+    },
+    "taprpcTapLeaf": {
+      "type": "object",
+      "properties": {
+        "script": {
+          "type": "string",
+          "format": "byte",
+          "description": "The script of the tap leaf."
+        }
+      }
+    },
+    "taprpcTapscriptFullTree": {
+      "type": "object",
+      "properties": {
+        "all_leaves": {
+          "type": "array",
+          "items": {
+            "$ref": "#/definitions/taprpcTapLeaf"
+          },
+          "description": "The complete, ordered list of all tap leaves of the tree."
+        }
+      }
     }
   }
 }