Add more format validation and better error messages

src/explorers/index.ts

@@ -7,6 +7,7 @@ import { TRANSACTION_APIS } from '../constants/api';
 import { ExplorerAPI, TExplorerFunctionsArray } from '../models/Explorers';
 import { ethereumRPCParsingFunction } from './rpc/ethereum';
 import { bitcoinRPCParsingFunction } from './rpc/bitcoin';
+import ensureExplorerAPIValidity from '../utils/ensureExplorerAPIValidity';
 
 export interface TDefaultExplorersPerBlockchain {
   bitcoin: TExplorerFunctionsArray;
@@ -93,6 +94,7 @@ export function getRPCExplorers (customExplorerAPIs?: ExplorerAPI[]): Partial<TE
 }
 
 export function prepareExplorerAPIs (customExplorerAPIs: ExplorerAPI[]): TExplorerAPIs {
+  ensureExplorerAPIValidity(customExplorerAPIs);
   const { bitcoin, ethereum } = getDefaultExplorers(customExplorerAPIs);
   const { custom: rpcCustomExplorers } = getRPCExplorers(customExplorerAPIs.filter(e => e.apiType === 'rpc'));
   const restCustomExplorers = explorerFactory(customExplorerAPIs.filter(e => e.apiType !== 'rpc'));

src/utils/ensureExplorerAPIValidity.ts

@@ -1,7 +1,7 @@
 import { ExplorerAPI } from '../models/Explorers';
 
 function isPriorityValid (explorerAPI: ExplorerAPI): boolean {
-  return explorerAPI.priority >= 0;
+  return explorerAPI.priority >= 0 && explorerAPI.priority <= 1;
 }
 
 function isParsingFunctionValid (explorerAPI: ExplorerAPI): boolean {
@@ -14,11 +14,13 @@ export default function ensureExplorerAPIValidity (explorerAPIs: ExplorerAPI[] =
   }
 
   if (explorerAPIs.some(explorerAPI => !isPriorityValid(explorerAPI))) {
-    throw new Error('One or more of your custom explorer APIs has a priority set below zero');
+    throw new Error('One or more of your custom explorer APIs has a priority set below 0 or above 1. ' +
+      'Use 0 to give precedence to custom explorers over the default ones, or 1 for the contrary.');
   }
 
   if (explorerAPIs.some(explorerAPI => !isParsingFunctionValid(explorerAPI))) {
-    throw new Error('One or more of your custom explorer APIs does not have a parsing function');
+    throw new Error('One or more of your custom explorer APIs does not have a parsing function. ' +
+      'Parsing functions are required to convert the data received from the explorer.');
   }
 
   return true;

tests/explorers/explorer.test.ts

@@ -290,5 +290,27 @@ describe('Blockchain Explorers test suite', function () {
         expect(JSON.stringify(output)).toEqual(JSON.stringify(expectedExplorers));
       });
     });
+
+    describe('given the explorers provided are invalid', function () {
+      it('should throw an error', function () {
+        const fixtureCustomExplorerAPI: ExplorerAPI[] = [{
+          serviceURL: 'https://explorer-example.com',
+          priority: -1,
+          parsingFunction: (): TransactionData => {
+            return {
+              remoteHash: 'a',
+              issuingAddress: 'b',
+              time: 'c',
+              revokedAddresses: ['d']
+            };
+          }
+        }];
+        const expectedExplorers: TExplorerAPIs = getDefaultExplorers();
+        expectedExplorers.custom = explorerFactory(fixtureCustomExplorerAPI);
+        expect(() => prepareExplorerAPIs(fixtureCustomExplorerAPI))
+          .toThrow('One or more of your custom explorer APIs has a priority set below 0 or above 1. ' +
+            'Use 0 to give precedence to custom explorers over the default ones, or 1 for the contrary.');
+      });
+    });
   });
 });

tests/lookForTx/lookForTx.test.ts

@@ -4,12 +4,13 @@ import * as explorers from '../../src/explorers';
 import { TransactionData } from '../../src/models/TransactionData';
 import CONFIG from '../../src/constants/config';
 import lookForTx, { getExplorersByChain } from '../../src/lookForTx';
+import { ExplorerAPI } from '../../src/models/Explorers';
 
 describe('lookForTx test suite', function () {
   const MOCK_TRANSACTION_ID = 'mock-transaction-id';
 
   describe('given there are no custom explorers', function () {
-    it('should call and resolve from the explorers passed', async function () {
+    it('should call and resolve from the default explorers', async function () {
       const mockTxData: TransactionData = {
         revokedAddresses: [],
         time: '2020-04-20T00:00:00Z',
@@ -33,7 +34,56 @@ describe('lookForTx test suite', function () {
     });
   });
 
-  describe('given it is called with a transactionId, a chain and a certificateVersion', function () {
+  describe('given some custom explorers are passed', function () {
+    describe('when it is a valid custom explorer API object', function () {
+      describe('and the custom explorer API is set an invalid priority', function () {
+        it('should throw an error', async function () {
+          const fixtureExplorerAPI: ExplorerAPI[] = [{
+            serviceURL: 'https://explorer-example.com',
+            priority: -1,
+            parsingFunction: (): TransactionData => {
+              return {
+                remoteHash: 'a',
+                issuingAddress: 'b',
+                time: 'c',
+                revokedAddresses: ['d']
+              };
+            }
+          }];
+
+          await expect(async () => {
+            await lookForTx({
+              transactionId: 'a-transaction-id',
+              chain: SupportedChains.Bitcoin,
+              explorerAPIs: fixtureExplorerAPI
+            });
+          }).rejects.toThrow('One or more of your custom explorer APIs has a priority set below 0 or above 1. ' +
+            'Use 0 to give precedence to custom explorers over the default ones, or 1 for the contrary.');
+        });
+      });
+
+      describe('and the custom explorer API has a missing parsing function', function () {
+        it('should throw an error', async function () {
+          const fixtureExplorerAPI: ExplorerAPI[] = [{
+            serviceURL: 'https://explorer-example.com',
+            priority: 0,
+            parsingFunction: undefined
+          }];
+
+          await expect(async () => {
+            await lookForTx({
+              transactionId: 'a-transaction-id',
+              chain: SupportedChains.Bitcoin,
+              explorerAPIs: fixtureExplorerAPI
+            });
+          }).rejects.toThrow('One or more of your custom explorer APIs does not have a parsing function. ' +
+            'Parsing functions are required to convert the data received from the explorer.');
+        });
+      });
+    });
+  });
+
+  describe('given it is called with a transactionId and a chain', function () {
     describe('given the chain is invalid', function () {
       it('should throw an error', async function () {
         await expect(lookForTx({

tests/utils/ensureExplorerAPIValidity.test.ts

@@ -20,7 +20,8 @@ describe('ensureExplorerAPIValidity test suite', function () {
     it('should throw the right error', function () {
       expect(() => {
         ensureExplorerAPIValidity(fixtureExplorerAPIs);
-      }).toThrow('One or more of your custom explorer APIs has a priority set below zero');
+      }).toThrow('One or more of your custom explorer APIs has a priority set below 0 or above 1. ' +
+        'Use 0 to give precedence to custom explorers over the default ones, or 1 for the contrary.');
     });
   });
 
@@ -34,7 +35,8 @@ describe('ensureExplorerAPIValidity test suite', function () {
     it('should throw the right error', function () {
       expect(() => {
         ensureExplorerAPIValidity(fixtureExplorerAPIs);
-      }).toThrow('One or more of your custom explorer APIs does not have a parsing function');
+      }).toThrow('One or more of your custom explorer APIs does not have a parsing function. ' +
+        'Parsing functions are required to convert the data received from the explorer.');
     });
   });