Handle empty state_changes array in contract details (#733)

* Handle empty state_change array in contract details

Signed-off-by: lukelee-sl <[email protected]>

* update errors to use predefined errors

Signed-off-by: lukelee-sl <[email protected]>

* remove redundant null check

Signed-off-by: lukelee-sl <[email protected]>

add utility function for brevity and clarity

Signed-off-by: lukelee-sl <[email protected]>

remove unused import

Signed-off-by: lukelee-sl <[email protected]>

Signed-off-by: lukelee-sl <[email protected]>

Author: lukelee-sl

packages/relay/src/lib/eth.ts

@@ -482,6 +482,7 @@ export class EthImpl implements Eth {
    */
   async getStorageAt(address: string, slot: string, blockNumberOrTag?: string | null, requestId?: string) : Promise<string> {
     const requestIdPrefix = formatRequestIdMessage(requestId);
+    this.logger.trace(`${requestIdPrefix} getStorageAt(address=${address}, slot=${slot}, blockNumberOrTag=${blockNumberOrTag})`);
     let result = EthImpl.zeroHex32Byte; // if contract or slot not found then return 32 byte 0
     const blockResponse  = await this.getHistoricalBlockResponse(blockNumberOrTag, false);
 
@@ -498,7 +499,7 @@ export class EthImpl implements Eth {
       // retrieve the contract result details
       await this.mirrorNodeClient.getContractResultsDetails(address, contractResult.results[0].timestamp)
         .then(contractResultDetails => {
-          if (contractResultDetails?.state_changes != null) {
+          if (EthImpl.isArrayNonEmpty(contractResultDetails?.state_changes)) {
             // filter the state changes to match slot and return value
             const stateChange = contractResultDetails.state_changes.find(stateChange => stateChange.slot === slot);
             result = stateChange.value_written;
@@ -1400,4 +1401,9 @@ export class EthImpl implements Eth {
 
     return contractAddress;
   }
+
+  static isArrayNonEmpty(input: any): boolean {
+    return Array.isArray(input) && input.length > 0;
+  }
+
 }

packages/relay/tests/lib/eth.spec.ts

@@ -42,6 +42,7 @@ import { Block, Transaction } from '../../src/lib/model';
 import constants from '../../src/lib/constants';
 import { SDKClient } from '../../src/lib/clients';
 import { SDKClientError } from '../../src/lib/errors/SDKClientError';
+
 const LRU = require('lru-cache');
 
 const logger = pino();
@@ -378,6 +379,18 @@ describe('Eth calls using MirrorNode', async function () {
     }
   };
 
+  const defaultDetailedContractResultsNullStateChange = {
+    ...defaultDetailedContractResults, ...{
+      'state_changes' : null
+    }
+  };
+
+  const defaultDetailedContractResultsEmptyArrayStateChange = {
+    ...defaultDetailedContractResults, ...{
+      'state_changes' : []
+    }
+  };
+
   const detailedContractResultNotFound = { "_status": { "messages": [{ "message": "No correlating transaction" }] } };
   const timeoutError = { "type": "Error", "message": "timeout of 10000ms exceeded" };
 
@@ -2213,8 +2226,40 @@ describe('Eth calls using MirrorNode', async function () {
         await ethImpl.getStorageAt(contractAddress1, defaultDetailedContractResults.state_changes[0].slot, EthImpl.numberTo0x(blockNumber));
       } catch (e: any) {
         hasError = true;
-        expect(e.code).to.equal(-32001);
-        expect(e.name).to.equal('Resource not found');
+        expect(e.code).to.equal(predefined.RESOURCE_NOT_FOUND().code);
+        expect(e.name).to.equal(predefined.RESOURCE_NOT_FOUND().name);
+      }
+      expect(hasError).to.be.true;
+    });
+
+    it('eth_getStorageAt should throw a predefined RESOURCE_NOT_FOUND when state_changes is null', async function () {
+      defaultDetailedContractResultsNullStateChange
+      mock.onGet(`blocks/${blockNumber}`).reply(200, defaultBlock);
+      mock.onGet(`contracts/${contractAddress1}/results?timestamp=lte:${defaultBlock.timestamp.to}&limit=1&order=desc`).reply(200, defaultContractResults);
+      mock.onGet(`contracts/${contractAddress1}/results/${contractTimestamp1}`).reply(200, defaultDetailedContractResultsNullStateChange);
+      let hasError = false;
+      try {
+        await ethImpl.getStorageAt(contractAddress1, defaultDetailedContractResults.state_changes[0].slot, EthImpl.numberTo0x(blockNumber));
+      } catch (e: any) {
+        hasError = true;
+        expect(e.code).to.equal(predefined.RESOURCE_NOT_FOUND().code);
+        expect(e.name).to.equal(predefined.RESOURCE_NOT_FOUND().name);
+      }
+      expect(hasError).to.be.true;
+    });
+
+    it('eth_getStorageAt should throw a predefined RESOURCE_NOT_FOUND when state_changes is an empty array', async function () {
+      defaultDetailedContractResultsNullStateChange
+      mock.onGet(`blocks/${blockNumber}`).reply(200, defaultBlock);
+      mock.onGet(`contracts/${contractAddress1}/results?timestamp=lte:${defaultBlock.timestamp.to}&limit=1&order=desc`).reply(200, defaultContractResults);
+      mock.onGet(`contracts/${contractAddress1}/results/${contractTimestamp1}`).reply(200, defaultDetailedContractResultsEmptyArrayStateChange);
+      let hasError = false;
+      try {
+        await ethImpl.getStorageAt(contractAddress1, defaultDetailedContractResults.state_changes[0].slot, EthImpl.numberTo0x(blockNumber));
+      } catch (e: any) {
+        hasError = true;
+        expect(e.code).to.equal(predefined.RESOURCE_NOT_FOUND().code);
+        expect(e.name).to.equal(predefined.RESOURCE_NOT_FOUND().name);
       }
       expect(hasError).to.be.true;
     });
@@ -2230,8 +2275,8 @@ describe('Eth calls using MirrorNode', async function () {
         await ethImpl.getStorageAt(contractAddress1, defaultDetailedContractResults.state_changes[0].slot, EthImpl.numberTo0x(blockNumber));
       } catch (e: any) {
         hasError = true;
-        expect(e.code).to.equal(-32001);
-        expect(e.name).to.equal('Resource not found');
+        expect(e.code).to.equal(predefined.RESOURCE_NOT_FOUND().code);
+        expect(e.name).to.equal(predefined.RESOURCE_NOT_FOUND().name);
       }
       expect(hasError).to.be.true;
     });