add token owners

generated/schema.ts

@@ -525,9 +525,9 @@ export class Minted extends Entity {
 
 // 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) {
+  constructor(id: string) {
     super();
-    this.set("id", Value.fromBigInt(id));
+    this.set("id", Value.fromString(id));
   }
 
   save(): void {
@@ -535,28 +535,28 @@ export class TokenOwner extends Entity {
     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 ${id.displayKind()}`,
+        id.kind == ValueKind.STRING,
+        `Entities of type TokenOwner must have an ID of type string but the id '${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()));
+  static load(id: string): TokenOwner | null {
+    return changetype<TokenOwner | null>(store.get("TokenOwner", id));
   }
 
-  get id(): BigInt {
+  get id(): string {
     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();
+      return value.toString();
     }
   }
 
-  set id(value: BigInt) {
-    this.set("id", Value.fromBigInt(value));
+  set id(value: string) {
+    this.set("id", Value.fromString(value));
   }
 
   get owner(): Bytes {

schema.graphql

@@ -42,7 +42,7 @@ type ApprovalForAll @entity(immutable: true) {
 
 // add TokenOwner entity
 type TokenTransfer @entity(immutable: true) {
-  id: BigInt!
+  id: string!
   owner: Bytes! #address
   tokenId: BigInt! # uint256
 }
\ No newline at end of file

src/drago.ts

@@ -26,7 +26,7 @@ export function handleTransfer(event: TransferEvent): void {
   entity.save()
   // update TokenOwner
   if (true) {
-    let ownerEntity= new TokenOwner(event.params.tokenId)
+    let ownerEntity= new TokenOwner(event.params.tokenId.toString())
     ownerEntity.owner = event.params.to
     ownerEntity.tokenId = event.params.tokenId
     ownerEntity.save()