feat: track future cashflows per asset (#219)

* feat: track future cashflows per asset
Fixes #196

* feat: track future cashflows
Closes #196
Closes #220

* chore: record cashflows for debt transfers

* fix: runtime typing

schema.graphql

@@ -341,6 +341,15 @@ type AssetTransaction @entity {
  realizedProfitFifo: BigInt
 }
 
+type AssetCashflow @entity {
+ id: ID! # pool id - asset id - cf timestamp
+ asset: Asset! @index
+
+ timestamp: Date!
+ principal: BigInt!
+ interest: BigInt!
+}
+
 type OracleTransaction @entity {
  id: ID! # extrinsic hash - timestamp - oracle key
  timestamp: Date!

src/chaintypes.ts

@@ -1,6 +1,4 @@
-import type { OverrideBundleDefinition } from '@polkadot/types/types'
-
-/* eslint-disable sort-keys */
+import type { DefinitionsCallEntry, OverrideBundleDefinition } from '@polkadot/types/types'
 
 const latestTypes = {
  ActiveLoanInfoV2: {
@@ -36,6 +34,61 @@ const latestTypes = {
  bucket: 'CfgTraitsFeePoolFeeBucket',
  fees: 'Vec<CfgTypesPoolsPoolFee>',
  },
+ CashflowPayment: {
+ when: 'u64',
+ principal: 'Balance',
+ interest: 'Balance',
+ },
+}
+
+const loansRuntimeApiMethodsV1: DefinitionsCallEntry['methods'] = {
+ portfolio: {
+ description: 'Get active pool loan',
+ params: [
+ {
+ name: 'pool_id',
+ type: 'u64',
+ },
+ ],
+ type: 'Vec<(u64, ActiveLoanInfoV1)>',
+ },
+ portfolio_loan: {
+ description: 'Get active pool loan',
+ params: [
+ {
+ name: 'pool_id',
+ type: 'u64',
+ },
+ {
+ name: 'loan_id',
+ type: 'u64',
+ },
+ ],
+ type: 'Option<PalletLoansEntitiesLoansActiveLoan>',
+ },
+}
+
+const loansRuntimeApiMethodsV2: DefinitionsCallEntry['methods'] = {
+ ...loansRuntimeApiMethodsV1,
+ portfolio: { ...loansRuntimeApiMethodsV1.portfolio, type: 'Vec<(u64, ActiveLoanInfoV2)>' },
+}
+
+const loansRuntimeApiMethodsV3: DefinitionsCallEntry['methods'] = {
+ ...loansRuntimeApiMethodsV2,
+ expected_cashflows: {
+ description: 'Retrieve expected cashflows',
+ params: [
+ {
+ name: 'pool_id',
+ type: 'u64',
+ },
+ {
+ name: 'loan_id',
+ type: 'u64',
+ },
+ ],
+ type: 'Result<Vec<CashflowPayment<Balance>>, SpRuntimeDispatchError>',
+ },
 }
 
 const definitions: OverrideBundleDefinition = {
@@ -47,64 +100,9 @@ const definitions: OverrideBundleDefinition = {
  ],
  runtime: {
  LoansApi: [
- {
- methods: {
- portfolio: {
- description: 'Get active pool loan',
- params: [
- {
- name: 'pool_id',
- type: 'u64',
- },
- ],
- type: 'Vec<(u64, ActiveLoanInfoV2)>',
- },
- portfolio_loan: {
- description: 'Get active pool loan',
- params: [
- {
- name: 'pool_id',
- type: 'u64',
- },
- {
- name: 'loan_id',
- type: 'u64',
- },
- ],
- type: 'Option<PalletLoansEntitiesLoansActiveLoan>',
- },
- },
- version: 2,
- },
- {
- methods: {
- portfolio: {
- description: 'Get active pool loan',
- params: [
- {
- name: 'pool_id',
- type: 'u64',
- },
- ],
- type: 'Vec<(u64, ActiveLoanInfoV1)>',
- },
- portfolio_loan: {
- description: 'Get active pool loan',
- params: [
- {
- name: 'pool_id',
- type: 'u64',
- },
- {
- name: 'loan_id',
- type: 'u64',
- },
- ],
- type: 'Option<PalletLoansEntitiesLoansActiveLoan>',
- },
- },
- version: 1,
- },
+ { methods: loansRuntimeApiMethodsV3, version: 3 },
+ { methods: loansRuntimeApiMethodsV2, version: 2 },
+ { methods: loansRuntimeApiMethodsV1, version: 1 },
  ],
  PoolsApi: [
  {

src/helpers/types.ts

@@ -1,6 +1,6 @@
 //find out types: const a = createType(api.registry, '[u8;32]', 18)
 import { AugmentedCall, AugmentedRpc, PromiseRpcResult } from '@polkadot/api/types'
-import { Enum, Null, Struct, u128, u32, u64, U8aFixed, Option, Vec, Bytes } from '@polkadot/types'
+import { Enum, Null, Struct, u128, u32, u64, U8aFixed, Option, Vec, Bytes, Result } from '@polkadot/types'
 import { AccountId32, Perquintill, Balance } from '@polkadot/types/interfaces'
 import { ITuple, Observable } from '@polkadot/types/types'
 
@@ -265,7 +265,7 @@ export interface LoanPricing extends Enum {
  asExternal: {
  priceId: OracleKey
  maxBorrowAmount: LoanExternalPricingMaxBorrowAmount
- notional: u128,
+ notional: u128
  maxPriceVariation: u128
  }
 }
@@ -403,32 +403,40 @@ export interface PoolFee extends Struct {
 }
 
 export interface OracleKey extends Enum {
- readonly isIsin: boolean;
-  readonly asIsin: U8aFixed;
-  readonly isConversionRatio: boolean;
-  readonly asConversionRatio: ITuple<[TokensCurrencyId, TokensCurrencyId]>;
-  readonly isPoolLoanId: boolean;
-  readonly asPoolLoanId: ITuple<[u64, u64]>;
-  readonly type: 'Isin' | 'ConversionRatio' | 'PoolLoanId';
+ readonly isIsin: boolean
+ readonly asIsin: U8aFixed
+ readonly isConversionRatio: boolean
+ readonly asConversionRatio: ITuple<[TokensCurrencyId, TokensCurrencyId]>
+ readonly isPoolLoanId: boolean
+ readonly asPoolLoanId: ITuple<[u64, u64]>
+ readonly type: 'Isin' | 'ConversionRatio' | 'PoolLoanId'
 }
 
 interface DevelopmentRuntimeOriginCaller extends Enum {
- readonly isSystem: boolean;
- readonly asSystem: unknown//FrameSupportDispatchRawOrigin;
- readonly isVoid: boolean;
- readonly isCouncil: boolean;
+ readonly isSystem: boolean
+ readonly asSystem: unknown //FrameSupportDispatchRawOrigin;
+ readonly isVoid: boolean
+ readonly isCouncil: boolean
  readonly asCouncil: unknown //PalletCollectiveRawOrigin;
- readonly isLiquidityPoolsGateway: boolean;
+ readonly isLiquidityPoolsGateway: boolean
  readonly asLiquidityPoolsGateway: unknown //PalletLiquidityPoolsGatewayOriginGatewayOrigin;
- readonly isPolkadotXcm: boolean;
- readonly asPolkadotXcm: unknown//PalletXcmOrigin;
- readonly isCumulusXcm: boolean;
+ readonly isPolkadotXcm: boolean
+ readonly asPolkadotXcm: unknown //PalletXcmOrigin;
+ readonly isCumulusXcm: boolean
  readonly asCumulusXcm: unknown //CumulusPalletXcmOrigin;
- readonly isEthereum: boolean;
+ readonly isEthereum: boolean
  readonly asEthereum: unknown //PalletEthereumRawOrigin;
- readonly type: 'System' | 'Void' | 'Council' | 'LiquidityPoolsGateway' | 'PolkadotXcm' | 'CumulusXcm' | 'Ethereum';
+ readonly type: 'System' | 'Void' | 'Council' | 'LiquidityPoolsGateway' | 'PolkadotXcm' | 'CumulusXcm' | 'Ethereum'
+}
+
+export interface CashflowPayment extends Struct {
+ when: u64
+ principal: Balance
+ interest: Balance
 }
 
+export interface DispatchError extends Enum {}
+
 export type LoanAsset = ITuple<[collectionId: u64, itemId: u128]>
 export type LoanCreatedEvent = ITuple<[poolId: u64, loanId: u64, loanInfo: LoanInfoCreated]>
 export type LoanClosedEvent = ITuple<[poolId: u64, loanId: u64, collateralInfo: LoanAsset]>
@@ -492,6 +500,10 @@ export type ExtendedRpc = typeof api.rpc & {
 export type ExtendedCall = typeof api.call & {
  loansApi: {
  portfolio: AugmentedCall<'promise', (poolId: string) => Observable<Vec<ITuple<[u64, LoanInfoActivePortfolio]>>>>
+ expectedCashflows: AugmentedCall<
+ 'promise',
+ (poolId: string, loanId: string) => Observable<Result<Vec<CashflowPayment>, DispatchError>>
+ >
  }
  poolsApi: {
  nav: AugmentedCall<'promise', (poolId: string) => Observable<Option<PoolNav>>>

src/mappings/handlers/loansHandlers.ts

@@ -18,6 +18,7 @@ import { AssetType, AssetValuationMethod } from '../../types'
 import { bnToBn, nToBigInt } from '@polkadot/util'
 import { WAD } from '../../config'
 import { AssetPositionService } from '../services/assetPositionService'
+import { AssetCashflowService } from '../services/assetCashflowService'
 
 export const handleLoanCreated = errorHandler(_handleLoanCreated)
 async function _handleLoanCreated(event: SubstrateEvent<LoanCreatedEvent>) {
@@ -96,6 +97,9 @@ async function _handleLoanCreated(event: SubstrateEvent<LoanCreatedEvent>) {
  // Update pool info
  await pool.increaseNumberOfAssets()
  await pool.save()
+
+ // Record cashflows
+ await AssetCashflowService.recordAssetCashflows(asset.id)
 }
 
 export const handleLoanBorrowed = errorHandler(_handleLoanBorrowed)
@@ -168,6 +172,9 @@ async function _handleLoanBorrowed(event: SubstrateEvent<LoanBorrowedEvent>): Pr
  await epoch.save()
  }
  await asset.save()
+
+ // Record cashflows
+ await AssetCashflowService.recordAssetCashflows(asset.id)
 }
 
 export const handleLoanRepaid = errorHandler(_handleLoanRepaid)
@@ -245,22 +252,28 @@ async function _handleLoanRepaid(event: SubstrateEvent<LoanRepaidEvent>) {
  }
 
  await asset.save()
+
+ // Record cashflows
+ await AssetCashflowService.recordAssetCashflows(asset.id)
 }
 
 export const handleLoanWrittenOff = errorHandler(_handleLoanWrittenOff)
 async function _handleLoanWrittenOff(event: SubstrateEvent<LoanWrittenOffEvent>) {
  const [poolId, loanId, status] = event.event.data
  logger.info(`Loan writtenoff event for pool: ${poolId.toString()} loanId: ${loanId.toString()}`)
  const { percentage, penalty } = status
- const loan = await AssetService.getById(poolId.toString(), loanId.toString())
- await loan.writeOff(percentage.toBigInt(), penalty.toBigInt())
- await loan.save()
+ const asset = await AssetService.getById(poolId.toString(), loanId.toString())
+ await asset.writeOff(percentage.toBigInt(), penalty.toBigInt())
+ await asset.save()
 
  const pool = await PoolService.getById(poolId.toString())
  if (pool === undefined) throw missingPool
 
- await pool.increaseWriteOff(loan.writtenOffAmountByPeriod)
+ await pool.increaseWriteOff(asset.writtenOffAmountByPeriod)
  await pool.save()
+
+ // Record cashflows
+ await AssetCashflowService.recordAssetCashflows(asset.id)
 }
 
 export const handleLoanClosed = errorHandler(_handleLoanClosed)
@@ -273,9 +286,9 @@ async function _handleLoanClosed(event: SubstrateEvent<LoanClosedEvent>) {
 
  const account = await AccountService.getOrInit(event.extrinsic.extrinsic.signer.toHex())
 
- const loan = await AssetService.getById(poolId.toString(), loanId.toString())
- await loan.close()
- await loan.save()
+ const asset = await AssetService.getById(poolId.toString(), loanId.toString())
+ await asset.close()
+ await asset.save()
 
  const epoch = await EpochService.getById(pool.id, pool.currentEpoch)
  if (!epoch) throw new Error('Epoch not found!')
@@ -289,6 +302,9 @@ async function _handleLoanClosed(event: SubstrateEvent<LoanClosedEvent>) {
  timestamp: event.block.timestamp,
  })
  await at.save()
+
+ // Record cashflows
+ await AssetCashflowService.recordAssetCashflows(asset.id)
 }
 
 export const handleLoanDebtTransferred = errorHandler(_handleLoanDebtTransferred)
@@ -375,6 +391,9 @@ async function _handleLoanDebtTransferred(event: SubstrateEvent<LoanDebtTransfer
  realizedProfitFifo,
  })
  await principalRepayment.save()
+
+ // Record cashflows
+ await AssetCashflowService.recordAssetCashflows(principalRepayment.assetId)
  }
 
  if (fromAsset.isOffchainCash() && toAsset.isNonCash()) {
@@ -415,6 +434,9 @@ async function _handleLoanDebtTransferred(event: SubstrateEvent<LoanDebtTransfer
  fromAssetId: fromLoanId.toString(10),
  })
  await purchaseTransaction.save()
+
+ // Record cashflows
+ await AssetCashflowService.recordAssetCashflows(purchaseTransaction.assetId)
  }
 }
 

src/mappings/services/assetCashflowService.ts

@@ -0,0 +1,37 @@
+import { ExtendedCall } from '../../helpers/types'
+import { AssetCashflow } from '../../types/models/AssetCashflow'
+
+export class AssetCashflowService extends AssetCashflow {
+ static init(assetId: string, timestamp: Date, principal: bigint, interest: bigint) {
+ const id = `${assetId}-${timestamp.valueOf()}`
+ logger.info(`Initialising new AssetCashflow with Id ${id}`)
+ return new this(id, assetId, timestamp, principal, interest)
+ }
+
+ static async recordAssetCashflows(_assetId: string) {
+ const specVersion = api.runtimeVersion.specVersion.toNumber()
+ if (specVersion < 1103) return
+ const [poolId, assetId] = _assetId.split('-')
+ logger.info(`Recording AssetCashflows for Asset ${_assetId}`)
+ const apiCall = api.call as ExtendedCall
+ logger.info(`Calling runtime API loansApi.expectedCashflows(${poolId}, ${assetId})`)
+ const response = await apiCall.loansApi.expectedCashflows(poolId, assetId)
+ logger.info(JSON.stringify(response))
+ if(!response.isOk) return
+ await this.clearAssetCashflows(_assetId)
+ const saves = response.asOk.map((cf) => {
+ const { when, principal, interest } = cf
+ const timestamp = new Date(when.toNumber() * 1000)
+ const cashflow = this.init(_assetId, timestamp, principal.toBigInt(), interest.toBigInt())
+ return cashflow.save()
+ })
+ return Promise.all(saves)
+ }
+
+ static async clearAssetCashflows(assetId: string) {
+ logger.info(`Clearing AssetCashflows for asset: ${assetId}`)
+ const cashflows = await this.getByAssetId(assetId)
+ const deletes = cashflows.map((cf) => this.remove(cf.id))
+ return Promise.all(deletes)
+ }
+}