Implement method for storage based access in subgraph mapping code (#162)

* Implement storage call in subgraph mapping code

* Add test for mapping type variable storage call

* Use vulcanize graph-ts

* Revert to graph-ts version 0.22.1

packages/graph-node/test/utils/index.ts

@@ -4,12 +4,15 @@
 
 import { BaseProvider } from '@ethersproject/providers';
 import { getCustomProvider } from '@vulcanize/util';
+import { EthClient } from '@vulcanize/ipld-eth-client';
+import { StorageLayout } from '@vulcanize/solidity-mapper';
 
 import { EventData } from '../../src/utils';
 import { Database } from '../../src/database';
 import { Indexer } from './indexer';
 
 const NETWORK_URL = 'http://127.0.0.1:8081';
+const IPLD_ETH_SERVER_GQL_URL = 'http://127.0.0.1:8082/graphql';
 
 export const ZERO_ADDRESS = '0x0000000000000000000000000000000000000000';
 export const ZERO_HASH = '0x0000000000000000000000000000000000000000000000000000000000000000';
@@ -71,8 +74,13 @@ export const getTestDatabase = (): Database => {
   return new Database({ type: 'postgres' }, '');
 };
 
-export const getTestIndexer = (): Indexer => {
-  return new Indexer();
+export const getTestIndexer = (storageLayout?: Map<string, StorageLayout>): Indexer => {
+  const ethClient = new EthClient({
+    gqlEndpoint: IPLD_ETH_SERVER_GQL_URL,
+    cache: undefined
+  });
+
+  return new Indexer(ethClient, storageLayout);
 };
 
 export const getTestProvider = (): BaseProvider => {

packages/graph-node/test/utils/indexer.ts

@@ -6,14 +6,43 @@ import {
   BlockProgressInterface,
   EventInterface,
   SyncStatusInterface,
-  ServerConfig as ServerConfigInterface
+  ServerConfig as ServerConfigInterface,
+  ValueResult
 } from '@vulcanize/util';
+import { EthClient } from '@vulcanize/ipld-eth-client';
+import { GetStorageAt, getStorageValue, MappingKey, StorageLayout } from '@vulcanize/solidity-mapper';
 
 export class Indexer implements IndexerInterface {
+  _getStorageAt: GetStorageAt;
+  _storageLayoutMap: Map<string, StorageLayout> = new Map()
+
+  constructor (ethClient: EthClient, storageLayoutMap?: Map<string, StorageLayout>) {
+    this._getStorageAt = ethClient.getStorageAt.bind(ethClient);
+
+    if (storageLayoutMap) {
+      this._storageLayoutMap = storageLayoutMap;
+    }
+  }
+
   get serverConfig () {
     return new ServerConfig();
   }
 
+  get storageLayoutMap (): Map<string, StorageLayout> {
+    return this._storageLayoutMap;
+  }
+
+  async getStorageValue (storageLayout: StorageLayout, blockHash: string, contractAddress: string, variable: string, ...mappingKeys: MappingKey[]): Promise<ValueResult> {
+    return getStorageValue(
+      storageLayout,
+      this._getStorageAt,
+      blockHash,
+      contractAddress,
+      variable,
+      ...mappingKeys
+    );
+  }
+
   async getBlockProgress (blockHash: string): Promise<BlockProgressInterface | undefined> {
     assert(blockHash);