add token owners

generated/schema.ts

@@ -522,3 +522,66 @@ export class Minted extends Entity {
     this.set("transactionHash", Value.fromBytes(value));
   }
 }
+
+// add a entity to store token id to owner, id use token id, and owner use address.
+export class TokenOwner extends Entity {
+  constructor(id: BigInt) {
+    super();
+    this.set("id", Value.fromBigInt(id));
+  }
+
+  save(): void {
+    let id = this.get("id");
+    assert(id != null, "Cannot save TokenOwner entity without an ID");
+    if (id) {
+      assert(
+        id.kind == ValueKind.BIGINT,
+        `Entities of type TokenOwner must have an ID of type BigInt but the id '${id.displayData()}' is of type ${id.displayKind()}`,
+      );
+      store.set("TokenOwner", id.toString(), this);
+    }
+  }
+
+  static load(id: BigInt): TokenOwner | null {
+    return changetype<TokenOwner | null>(store.get("TokenOwner", id.toString()));
+  }
+
+  get id(): BigInt {
+    let value = this.get("id");
+    if (!value || value.kind == ValueKind.NULL) {
+      throw new Error("Cannot return null for a required field.");
+    } else {
+      return value.toBigInt();
+    }
+  }
+
+  set id(value: BigInt) {
+    this.set("id", Value.fromBigInt(value));
+  }
+
+  get owner(): Bytes {
+    let value = this.get("owner");
+    if (!value || value.kind == ValueKind.NULL) {
+      throw new Error("Cannot return null for a required field.");
+    } else {
+      return value.toBytes();
+    }
+  }
+
+  set owner(value: Bytes) {
+    this.set("owner", Value.fromBytes(value));
+  }
+
+  get tokenId(): BigInt {
+    let value = this.get("tokenId");
+    if (!value || value.kind == ValueKind.NULL) {
+      throw new Error("Cannot return null for a required field.");
+    } else {
+      return value.toBigInt();
+    }
+  }
+
+  set tokenId(value: BigInt) {
+    this.set("tokenId", Value.fromBigInt(value));
+  }
+}
\ No newline at end of file

schema.graphql

@@ -39,3 +39,10 @@ type ApprovalForAll @entity(immutable: true) {
   blockTimestamp: BigInt!
   transactionHash: Bytes!
 }
+
+// add TokenOwner entity
+type TokenTransfer @entity(immutable: true) {
+  id: BigInt!
+  owner: Bytes! #address
+  tokenId: BigInt! # uint256
+}
\ No newline at end of file

src/drago.ts

@@ -3,7 +3,7 @@ import {
   Approval as ApprovalEvent,
   ApprovalForAll as ApprovalForAllEvent
 } from "../generated/Drago/Drago"
-import { Transfer, Approval, ApprovalForAll, Minted } from "../generated/schema"
+import {Transfer, Approval, ApprovalForAll, Minted, TokenOwner} from "../generated/schema"
 import {
   store,
   Bytes,
@@ -24,6 +24,13 @@ export function handleTransfer(event: TransferEvent): void {
   entity.transactionHash = event.transaction.hash
 
   entity.save()
+  // update TokenOwner
+  if (true) {
+    let ownerEntity= new TokenOwner(event.params.tokenId)
+    ownerEntity.owner = event.params.to
+    ownerEntity.tokenId = event.params.tokenId
+    ownerEntity.save()
+  }
 
   if (event.params.from.toHexString() == "0x0000000000000000000000000000000000000000") {
     // Mint