Hashes for the NFTs

db/migrations/1645015239078-Data.js

@@ -0,0 +1,13 @@
+module.exports = class Data1645015239078 {
+  name = 'Data1645015239078'
+
+  async up(db) {
+    await db.query(`ALTER TABLE "nft_entity" ADD "hash" text NOT NULL`)
+    await db.query(`CREATE INDEX "IDX_16e57ac8478b6ea1f383e3eb03" ON "nft_entity" ("hash") `)
+  }
+
+  async down(db) {
+    await db.query(`ALTER TABLE "nft_entity" DROP COLUMN "hash"`)
+    await db.query(`DROP INDEX "public"."IDX_16e57ac8478b6ea1f383e3eb03"`)
+  }
+}

justfile

@@ -45,7 +45,7 @@ migrate:
 	@npx sqd db:migrate
 
 update NAME:
-	npx sqd db:create-migration -n "{{NAME}}"
+	npx sqd db:create-migration "{{NAME}}"
 
 test:
   npm run test:unit

package.json

@@ -22,6 +22,7 @@
     "class-validator": "^0.13.1",
     "dotenv": "^16.0.0",
     "inflected": "^2.1.0",
+    "md5": "^2.3.0",
     "nanoid": "^3.1.30",
     "signale": "^1.4.0",
     "type-graphql": "^1.2.0-rc.1"
@@ -31,6 +32,7 @@
     "@subsquid/substrate-typegen": "^0.2.1",
     "@types/chai": "^4.3.0",
     "@types/inflected": "^1.1.29",
+    "@types/md5": "^2.3.2",
     "@types/mocha": "^9.0.0",
     "@types/pg": "^8.6.1",
     "chai": "^4.3.4",

schema.graphql

@@ -37,6 +37,7 @@ type NFTEntity @entity {
   issuer: String
   sn: String
   id: ID!
+  hash: String! @index
   metadata: String
   currentOwner: String
   price: BigInt!

src/mappings/index.ts

@@ -39,6 +39,7 @@ import { create, get } from './utils/entity'
 import { fetchMetadata } from './utils/metadata'
 import { Store} from '@subsquid/substrate-processor'
 import {updateCache} from './utils/cache'
+import md5 from 'md5'
 
 
 export async function handleRemark(context: Context): Promise<void> {
@@ -158,8 +159,9 @@ async function mintNFT(
     canOrElseError<CollectionEntity>(exists, collection, true)
     isOwnerOrElseError(collection, remark.caller)
     const final = create<NFTEntity>(NFTEntity, collection.id, {})
-
-    final.id = getNftId(nft, remark.blockNumber)
+    const id = getNftId(nft, remark.blockNumber)
+    final.id = id
+    final.hash = md5(id)
     final.issuer = remark.caller
     final.currentOwner = remark.caller
     final.blockNumber = BigInt(remark.blockNumber)

src/model/generated/nftEntity.model.ts

@@ -33,6 +33,10 @@ export class NFTEntity {
   @PrimaryColumn_()
   id!: string
 
+  @Index_()
+  @Column_("text", {nullable: false})
+  hash!: string
+
   @Column_("text", {nullable: true})
   metadata!: string | undefined | null