Add supply indexing

project.ts

@@ -1,4 +1,8 @@
-import { CosmosDatasourceKind, CosmosHandlerKind, CosmosProject } from "@subql/types-cosmos";
+import {
+  CosmosDatasourceKind,
+  CosmosHandlerKind,
+  CosmosProject,
+} from "@subql/types-cosmos";
 
 import * as dotenv from "dotenv";
 import path from "path";

schema.graphql

@@ -9,6 +9,11 @@ type EventAttribute @entity {
   event: Event!
 }
 
+type SupplyDenom @entity {
+  # ID is the supply coin denomination.
+  id: ID!
+}
+
 type Block @entity {
   id: ID! # The block header hash
   chainId: String! @index
@@ -18,6 +23,7 @@ type Block @entity {
   messages: [Message] @derivedFrom(field: "block")
   events: [Event] @derivedFrom(field: "block")
   balancesOfAccountByDenom: [Balance] @derivedFrom(field: "lastUpdatedBlock")
+  supplies: [BlockSupply]! @derivedFrom(field: "block")
   # PARAMS
   appParams: [AppParam] @derivedFrom(field: "block")
   authParams: [AuthParam] @derivedFrom(field: "block")
@@ -585,3 +591,17 @@ type AuthzMsgExec @entity {
   authzExec: AuthzExec!
   message: Message!
 }
+
+type Supply @entity {
+  id: ID!
+  denom: String! @index
+  amount: BigInt!
+  blocks: [BlockSupply]! @derivedFrom(field: "supply")
+}
+
+# This entity is a Join between Block and Supply
+type BlockSupply @entity {
+  id: ID!
+  block: Block!
+  supply: Supply!
+}

src/mappings/bank/supply.ts

@@ -0,0 +1,88 @@
+import type {
+  Coin,
+  CosmosBlock,
+} from "@subql/types-cosmos";
+import type { QueryTotalSupplyResponse } from "cosmjs-types/cosmos/bank/v1beta1/query";
+import {
+  BlockSupply,
+  Supply,
+} from "../../types";
+import { stringify } from "../utils";
+
+export const getSupplyId = function(denom: string, height: number): string {
+  return `${denom}@${height}`;
+};
+
+export const getSupplyRecord = function(supply: Coin, block: CosmosBlock): Supply {
+  return Supply.create({
+    id: getSupplyId(supply.denom, block.header.height),
+    denom: supply.denom,
+    amount: BigInt(supply.amount),
+  });
+};
+
+export async function queryTotalSupply(): Promise<Coin[]> {
+  const finalSupply: Coin[] = [];
+  let paginationKey: Uint8Array | undefined;
+
+  try {
+    // Here we force the use of a private property, breaking typescript limitation, due to the need of call a total supply
+    // rpc query of cosmosjs that is not exposed on the implemented client by SubQuery team.
+    // To avoid this, we need to move to implement our own rpc client and also use `unsafe` parameter which I prefer to avoid.
+    // eslint-disable-next-line @typescript-eslint/ban-ts-comment
+    // @ts-ignore
+    const queryClient = api.forceGetQueryClient();
+
+    // Initial call to get the first set of results
+    const initialResponse: QueryTotalSupplyResponse = await queryClient.bank.totalSupply() as unknown as QueryTotalSupplyResponse;
+    logger.debug(`[handleTotalSupply]: initialResponse=${stringify(initialResponse, undefined, 2)}`);
+    finalSupply.push(...initialResponse.supply);
+    paginationKey = initialResponse.pagination?.nextKey;
+
+    // Continue fetching if there is a nextKey
+    while (paginationKey && paginationKey.length > 0) {
+      logger.debug(`[handleTotalSupply]: loading more supply pages pagination.nextKey=${JSON.stringify(paginationKey, undefined, 2)}`);
+      const response = await queryClient.bank.totalSupply(paginationKey);
+      finalSupply.push(...response.supply);
+      paginationKey = response.pagination?.nextKey;
+    }
+    logger.debug(`[handleTotalSupply]: all_total_supply=${JSON.stringify(finalSupply, undefined, 2)}`);
+  } catch (error) {
+    logger.error(`[handleTotalSupply] errored: ${error}`);
+  }
+
+  return finalSupply;
+}
+
+export async function _handleSupply(block: CosmosBlock): Promise<void> {
+  const totalSupply = await queryTotalSupply();
+  if (totalSupply.length === 0) {
+    logger.warn(`[_handleSupply]: no total supply found`);
+    return;
+  }
+
+  for (const supply of totalSupply) {
+    // get the current blockSupply create on block handler to been able to access the assigned previous supply id
+    // that will allow us to compare the amount and create a new on if needed.
+    const blockSupplyId = getSupplyId(supply.denom, block.header.height);
+    const latestBlockSupply = await BlockSupply.get(blockSupplyId);
+    if (!latestBlockSupply) {
+      logger.warn(`[_handleSupply]: no BlockSupply found id=${blockSupplyId}`);
+      continue;
+    }
+
+    const latestDenomSupply = await Supply.get(latestBlockSupply.supplyId);
+    if (!latestDenomSupply) {
+      logger.warn(`[_handleSupply]: no total supply found id=${latestBlockSupply.supplyId}`);
+      continue;
+    }
+
+    if (latestDenomSupply.amount.toString() !== supply.amount) {
+      const newSupply = getSupplyRecord(supply, block);
+      await newSupply.save();
+      latestBlockSupply.supplyId = newSupply.id;
+      await latestBlockSupply.save();
+      break;
+    }
+  }
+}