Subgraph: address issues pointed out by review (#687)

This commit addresses some issues pointed out by @danielattilasimon’s review.

- [x] Consistent `status` updates (fix troves being stuck in redeemed mode)
- [x] Simplify `getLeverageUpdate()`
- [x] `enterBatch()` and `leaveBatch()` now return the Trove
- [x] NFT transfers support
- [x] ~Fix collateral calculations~ removed, these were not used

subgraph/schema.graphql

@@ -7,9 +7,6 @@ type Collateral @entity {
   addresses: CollateralAddresses! @derivedFrom(field: "collateral")
   stabilityPoolDeposits: [StabilityPoolDeposit!]!
   @derivedFrom(field: "collateral")
-  totalDeposited: BigInt!
-  totalDebt: BigInt!
-  price: BigInt!
 }
 
 type Token @entity(immutable: true) {

subgraph/src/BoldToken.mapping.ts

@@ -7,7 +7,11 @@ import { CollateralRegistry as CollateralRegistryContract } from "../generated/B
 import { ERC20 as ERC20Contract } from "../generated/BoldToken/ERC20";
 import { TroveManager as TroveManagerContract } from "../generated/BoldToken/TroveManager";
 import { Collateral, CollateralAddresses, StabilityPoolEpochScale, Token } from "../generated/schema";
-import { StabilityPool as StabilityPoolTemplate, TroveManager as TroveManagerTemplate } from "../generated/templates";
+import {
+  StabilityPool as StabilityPoolTemplate,
+  TroveManager as TroveManagerTemplate,
+  TroveNFT as TroveNFTTemplate,
+} from "../generated/templates";
 
 function addCollateral(
   collIndex: i32,
@@ -20,9 +24,6 @@ function addCollateral(
   let collateral = new Collateral(collId);
   collateral.collIndex = collIndex;
   collateral.token = collId;
-  collateral.totalDebt = BigInt.fromI32(0);
-  collateral.totalDeposited = BigInt.fromI32(0);
-  collateral.price = BigInt.fromI32(0);
 
   let token = new Token(collId);
   let tokenContract = ERC20Contract.bind(tokenAddress);
@@ -68,6 +69,7 @@ function addCollateral(
   context.setI32("totalCollaterals", totalCollaterals);
 
   TroveManagerTemplate.createWithContext(troveManagerAddress, context);
+  TroveNFTTemplate.createWithContext(Address.fromBytes(addresses.troveNft), context);
   StabilityPoolTemplate.createWithContext(Address.fromBytes(addresses.stabilityPool), context);
 }
 

subgraph/src/TroveManager.mapping.ts

@@ -10,9 +10,9 @@ import { TroveNFT as TroveNFTContract } from "../generated/templates/TroveManage
 // decides whether to update the flag indicating
 // that a trove might be leveraged or not.
 enum LeverageUpdate {
-  yes = 0,
-  no = 1,
-  unchanged = 2,
+  yes,
+  no,
+  unchanged,
 }
 
 // see Operation enum in
@@ -49,7 +49,9 @@ export function handleTroveOperation(event: TroveOperationEvent): void {
   }
 
   if (operation === OP_ADJUST_TROVE) {
-    updateTrove(tm, troveId, timestamp, getLeverageUpdate(event), true);
+    trove = updateTrove(tm, troveId, timestamp, getLeverageUpdate(event), false);
+    trove.status = "active";
+    trove.save();
     return;
   }
 
@@ -65,17 +67,23 @@ export function handleTroveOperation(event: TroveOperationEvent): void {
   }
 
   if (operation === OP_ADJUST_TROVE_INTEREST_RATE) {
-    updateTrove(tm, troveId, timestamp, LeverageUpdate.unchanged, false);
+    trove = updateTrove(tm, troveId, timestamp, getLeverageUpdate(event), false);
+    trove.status = "active";
+    trove.save();
     return;
   }
 
   if (operation === OP_SET_INTEREST_BATCH_MANAGER) {
-    enterBatch(collId, troveId, tm.Troves(troveId).getInterestBatchManager());
+    trove = enterBatch(collId, troveId, tm.Troves(troveId).getInterestBatchManager());
+    trove.status = "active";
+    trove.save();
     return;
   }
 
   if (operation === OP_REMOVE_FROM_BATCH) {
-    leaveBatch(collId, troveId, event.params._annualInterestRate);
+    trove = leaveBatch(collId, troveId, event.params._annualInterestRate);
+    trove.status = "active";
+    trove.save();
     return;
   }
 
@@ -114,27 +122,14 @@ export function handleTroveOperation(event: TroveOperationEvent): void {
 }
 
 function getLeverageUpdate(event: TroveOperationEvent): LeverageUpdate {
-  let operation = event.params._operation;
-
-  // check if the operation involved a flash loan,
-  // which would indicate a potential leveraged update
-  if (
-    operation === OP_OPEN_TROVE
-    || operation === OP_OPEN_TROVE_AND_JOIN_BATCH
-    || operation === OP_ADJUST_TROVE
-    || operation === OP_ADJUST_TROVE_INTEREST_RATE
-  ) {
-    let receipt = event.receipt;
-    let logs = receipt ? receipt.logs : [];
-    for (let i = 0; i < logs.length; i++) {
-      if (logs[i].topics[0].equals(FLASH_LOAN_TOPIC)) {
-        return LeverageUpdate.yes;
-      }
+  let receipt = event.receipt;
+  let logs = receipt ? receipt.logs : [];
+  for (let i = 0; i < logs.length; i++) {
+    if (logs[i].topics[0].equals(FLASH_LOAN_TOPIC)) {
+      return LeverageUpdate.yes;
     }
-    return LeverageUpdate.no;
   }
-
-  return LeverageUpdate.unchanged;
+  return LeverageUpdate.no;
 }
 
 function floorToDecimals(value: BigInt, decimals: u8): BigInt {
@@ -150,25 +145,15 @@ function getRateFloored(rate: BigInt): BigInt {
 //  1. set the interest batch on the trove
 //  2. set the interest rate to 0 (indicating that the trove is in a batch)
 //  3. remove its debt from its rate bracket (handled at the batch level)
-function enterBatch(collId: string, troveId: BigInt, batchManager: Address): void {
+function enterBatch(collId: string, troveId: BigInt, batchManager: Address): Trove {
   let troveFullId = collId + ":" + troveId.toHexString();
   let batchId = collId + ":" + batchManager.toHexString();
 
   let trove = Trove.load(troveFullId);
-  if (!trove) {
+  if (trove === null) {
     throw new Error("Trove not found: " + troveFullId);
   }
 
-  // leave the previous batch if needed
-  if (trove.interestBatch !== null) {
-    leaveBatch(collId, troveId, BigInt.fromI32(0));
-  }
-
-  let batch = InterestBatch.load(batchId);
-  if (!batch) {
-    throw new Error("Batch not found: " + batchId);
-  }
-
   updateRateBracketDebt(
     collId,
     trove.interestRate,
@@ -180,30 +165,26 @@ function enterBatch(collId: string, troveId: BigInt, batchManager: Address): voi
   trove.interestBatch = batchId;
   trove.interestRate = BigInt.fromI32(0);
   trove.save();
+
+  return trove;
 }
 
 // When a trove leaves a batch:
 //  1. remove the interest batch on the trove
 //  2. set the interest rate to the new rate
 //  3. add its debt to the rate bracket of the current rate
-function leaveBatch(collId: string, troveId: BigInt, interestRate: BigInt): void {
+function leaveBatch(collId: string, troveId: BigInt, interestRate: BigInt): Trove {
   let troveFullId = collId + ":" + troveId.toHexString();
 
   let trove = Trove.load(troveFullId);
   if (trove === null) {
     throw new Error("Trove not found: " + troveFullId);
   }
 
-  let batchId = trove.interestBatch;
-  if (batchId === null) {
+  if (trove.interestBatch === null) {
     throw new Error("Trove is not in a batch: " + troveFullId);
   }
 
-  let batch = InterestBatch.load(batchId);
-  if (batch === null) {
-    throw new Error("Batch not found: " + batchId);
-  }
-
   updateRateBracketDebt(
     collId,
     BigInt.fromI32(0), // coming from rate 0 (in batch)
@@ -214,7 +195,10 @@ function leaveBatch(collId: string, troveId: BigInt, interestRate: BigInt): void
 
   trove.interestBatch = null;
   trove.interestRate = interestRate;
+  trove.status = "active"; // always reset the status when leaving a batch
   trove.save();
+
+  return trove;
 }
 
 function loadOrCreateInterestRateBracket(
@@ -350,7 +334,6 @@ function updateTrove(
   let trove = Trove.load(troveFullId);
 
   let prevDebt = trove ? trove.debt : BigInt.fromI32(0);
-  let prevDeposit = trove ? trove.deposit : BigInt.fromI32(0);
   let prevInterestRate = trove ? trove.interestRate : null;
 
   let troveData = troveManagerContract.getLatestTroveData(troveId);
@@ -359,8 +342,6 @@ function updateTrove(
   let newInterestRate = troveData.annualInterestRate;
   let newStake = troveManagerContract.Troves(troveId).getStake();
 
-  collateral.totalDeposited = collateral.totalDeposited.minus(prevDeposit).plus(newDeposit);
-  collateral.totalDebt = collateral.totalDebt.minus(prevDebt).plus(newDebt);
   collateral.save();
 
   // create trove if needed

subgraph/src/TroveNFT.mapping.ts

@@ -0,0 +1,68 @@
+import { Address, BigInt, dataSource } from "@graphprotocol/graph-ts";
+import { BorrowerInfo, Trove } from "../generated/schema";
+import { Transfer as TransferEvent } from "../generated/templates/TroveNFT/TroveNFT";
+
+enum BorrowerInfoUpdate {
+  add,
+  remove,
+}
+
+function updateBorrowerInfo(
+  borrowerAddress: Address,
+  troveFullId: string,
+  update: BorrowerInfoUpdate,
+): void {
+  let trove = Trove.load(troveFullId);
+  if (!trove) {
+    throw new Error("Trove does not exist: " + troveFullId);
+  }
+
+  let borrowerInfo = BorrowerInfo.load(borrowerAddress.toHexString());
+
+  if (!borrowerInfo && update == BorrowerInfoUpdate.add) {
+    borrowerInfo = new BorrowerInfo(borrowerAddress.toHexString());
+    borrowerInfo.troves = 0;
+
+    let totalCollaterals = dataSource.context().getI32("totalCollaterals");
+    borrowerInfo.trovesByCollateral = (new Array<i32>(totalCollaterals)).fill(0);
+  }
+
+  if (!borrowerInfo) {
+    throw new Error("BorrowerInfo does not exist: " + borrowerAddress.toHexString());
+  }
+
+  let diff = update == BorrowerInfoUpdate.add ? 1 : -1;
+
+  let trovesByColl = borrowerInfo.trovesByCollateral;
+  let collIndex = <i32> parseInt(trove.collateral);
+  trovesByColl[collIndex] += diff;
+
+  borrowerInfo.trovesByCollateral = trovesByColl;
+  borrowerInfo.troves += diff;
+  borrowerInfo.save();
+}
+
+export function handleTransfer(event: TransferEvent): void {
+  // Minting doesn’t need to be handled as we are already
+  // handling OP_OPEN_TROVE & OP_OPEN_TROVE_AND_JOIN_BATCH
+  // in TroveManager.mapping.ts.
+  if (event.params.from.equals(Address.zero())) {
+    return;
+  }
+
+  let collId = dataSource.context().getString("collId");
+  let troveFullId = collId + ":" + event.params.tokenId.toHexString();
+
+  // update BorrowerInfo for the previous owner
+  updateBorrowerInfo(event.params.from, troveFullId, BorrowerInfoUpdate.remove);
+
+  // update BorrowerInfo for the new owner (including zero address)
+  updateBorrowerInfo(event.params.to, troveFullId, BorrowerInfoUpdate.add);
+
+  // update the trove borrower
+  let trove = Trove.load(troveFullId);
+  if (trove) {
+    trove.borrower = event.params.to;
+    trove.save();
+  }
+}

subgraph/subgraph.yaml

@@ -27,6 +27,8 @@ dataSources:
           file: ../contracts/out/ERC20.sol/ERC20.json
         - name: TroveManager
           file: ../contracts/out/TroveManager.sol/TroveManager.json
+        - name: TroveNFT
+          file: ../contracts/out/TroveNFT.sol/TroveNFT.json
       eventHandlers:
         - event: CollateralRegistryAddressChanged(address)
           handler: handleCollateralRegistryAddressChanged
@@ -99,6 +101,25 @@ templates:
         - event: BatchUpdated(indexed
             address,uint8,uint256,uint256,uint256,uint256,uint256,uint256)
           handler: handleBatchUpdated
+  - name: TroveNFT
+    kind: ethereum/contract
+    network: sepolia
+    source:
+      abi: TroveNFT
+    mapping:
+      kind: ethereum/events
+      apiVersion: 0.0.9
+      language: wasm/assemblyscript
+      file: ./src/TroveNFT.mapping.ts
+      entities:
+        - BorrowerInfo
+        - Trove
+      abis:
+        - name: TroveNFT
+          file: ../contracts/out/TroveNFT.sol/TroveNFT.json
+      eventHandlers:
+        - event: Transfer(indexed address,indexed address,indexed uint256)
+          handler: handleTransfer
   - name: StabilityPool
     kind: ethereum/contract
     network: sepolia