DAO-528 Fixed transactions crashing due to .to.hash not being existent. Created new endpoint to fetch events by topic0 from an address. This is used to fetch governor ProposalCreated event - openapi.js implementation is pending. (#152)

Author: Freshenext

src/blockscoutApi/index.ts

@@ -11,6 +11,7 @@ import {
   fromApiToInternalTransaction, fromApiToNft, fromApiToNftOwner, fromApiToRtbcBalance, fromApiToTEvents,
   fromApiToTokenWithBalance, fromApiToTokens, fromApiToTransaction
 } from './utils'
+import { GetEventLogsByAddressAndTopic0 } from '../service/address/AddressService'
 
 export class BlockscoutAPI extends DataSource {
   private chainId: number
@@ -118,4 +119,30 @@ export class BlockscoutAPI extends DataSource {
     }
     return fromApiToNftOwner(address, [...(response?.items || []), ...items])
   }
+
+  async getEventLogsByAddressAndTopic0 ({
+    address, topic0, toBlock = 'latest', fromBlock
+  }: Omit<GetEventLogsByAddressAndTopic0, 'chainId'>) {
+    let fromBlockToUse = fromBlock
+    if (!fromBlock) {
+      const tx = await this.getTransactionsByAddress(address)
+      // @ts-ignore ignored because it's using never as type
+      const lastTx = tx.data.pop() // The last tx is the first transaction
+
+      if (lastTx) fromBlockToUse = lastTx.blockNumber
+    }
+
+    if (!fromBlockToUse) return []
+    const params = {
+      module: 'logs',
+      action: 'getLogs',
+      address: address.toLowerCase(),
+      toBlock,
+      fromBlock: fromBlockToUse,
+      topic0
+    }
+    return this.axios?.get<ServerResponse<TokenTransferApi>>(`${this.url}`, { params })
+      .then(({ data }) => data.result)
+      .catch(() => [])
+  }
 }

src/blockscoutApi/utils.ts

@@ -147,7 +147,7 @@ export const fromApiToTransaction = (transaction: TransactionServerResponse): IT
     blockNumber: transaction.block,
     transactionIndex: 0,
     from: transaction.from.hash,
-    to: transaction.to.hash,
+    to: transaction.to?.hash,
     gas: Number(transaction.gas_used),
     gasPrice: transaction.gas_price,
     value: transaction.value,
@@ -167,7 +167,7 @@ export const fromApiToTransaction = (transaction: TransactionServerResponse): IT
       contractAddress: null,
       logs: [],
       from: transaction.from.hash,
-      to: transaction.to.hash,
+      to: transaction.to?.hash,
       status: transaction.status === 'ok' ? '0x1' : '0x0',
       logsBloom: '',
       type: String(transaction.type)

src/controller/httpsAPI.ts

@@ -173,6 +173,27 @@ export class HttpsAPI {
         }
       })
 
+    this.app.get('/address/:address/eventsByTopic0',
+      async ({ params: { address }, query: { chainId = '31', topic0, fromBlock, toBlock } } : Request, res: Response,
+        nextFunction: NextFunction) => {
+        try {
+          chainIdSchema.validateSync({ chainId })
+          addressSchema.validateSync({ address })
+          const result = await this.addressService
+            .getEventLogsByAddressAndTopic0({
+              chainId: chainId as string,
+              address: address as string,
+              topic0: topic0 as string,
+              fromBlock: fromBlock as string,
+              toBlock: toBlock as string
+            })
+            .catch(nextFunction)
+          return this.responseJsonOk(res)(result)
+        } catch (e) {
+          this.handleValidationError(e, res)
+        }
+      })
+
     this.app.get(
       '/price',
       async (req: Request<{}, {}, {}, PricesQueryParams>, res: Response) => {

src/repository/DataSource.ts

@@ -1,6 +1,7 @@
 import _axios from 'axios'
 import { ethers } from 'ethers'
 import BitcoinCore from '../service/bitcoin/BitcoinCore'
+import { GetEventLogsByAddressAndTopic0 } from '../service/address/AddressService'
 
 export abstract class DataSource {
   readonly url: string
@@ -27,6 +28,8 @@ export abstract class DataSource {
 
   abstract getNft(address: string);
   abstract getNftOwnedByAddress(address: string, nft: string);
+  abstract getEventLogsByAddressAndTopic0({ address, topic0, toBlock, fromBlock } :
+    Omit<GetEventLogsByAddressAndTopic0, 'chainId'>);
 }
 
 export type RSKDatasource = {

src/rskExplorerApi/index.ts

@@ -139,4 +139,8 @@ export class RSKExplorerAPI extends DataSource {
   getNftOwnedByAddress () {
     throw new Error('Feature not supported')
   }
+
+  getEventLogsByAddressAndTopic0 () {
+    throw new Error('Feature not supported')
+  }
 }

src/service/address/AddressService.ts

@@ -33,6 +33,14 @@ interface GetNftsByAddress extends GetTokensByAddress {
   nftAddress: string
 }
 
+export interface GetEventLogsByAddressAndTopic0 {
+  address: string
+  topic0: string
+  toBlock: string
+  chainId: string
+  fromBlock?: string
+}
+
 type GetBalancesTransactionsPricesByAddress = {
   chainId: string
   address: string
@@ -139,4 +147,9 @@ export class AddressService {
     const dataSource = this.dataSourceMapping[chainId]
     return dataSource.getNftOwnedByAddress(address, nftAddress)
   }
+
+  async getEventLogsByAddressAndTopic0 ({ chainId, ...rest }: GetEventLogsByAddressAndTopic0) {
+    const dataSource = this.dataSourceMapping[chainId]
+    return dataSource.getEventLogsByAddressAndTopic0(rest)
+  }
 }