Refactor event scraping and add support for scraping ERC20 approval events (#1401)

* Refactor event scraping and add support for scraping ERC20 approval events

* Add tests for data_sources/contract-wrappers/utils

1 files changed, 26 insertions, 0 deletions

diff --git a/packages/pipeline/migrations/1544131464368-CreateERC20ApprovalEvents.ts b/packages/pipeline/migrations/1544131464368-CreateERC20ApprovalEvents.ts
new file mode 100644
index 000000000..2e84e0ec8
--- /dev/null
+++ b/packages/pipeline/migrations/1544131464368-CreateERC20ApprovalEvents.ts
@@ -0,0 +1,26 @@
+import { MigrationInterface, QueryRunner, Table } from 'typeorm';
+
+const erc20ApprovalEvents = new Table({
+    name: 'raw.erc20_approval_events',
+    columns: [
+        { name: 'token_address', type: 'varchar(42)', isPrimary: true },
+        { name: 'log_index', type: 'integer', isPrimary: true },
+        { name: 'block_number', type: 'bigint', isPrimary: true },
+
+        { name: 'raw_data', type: 'varchar' },
+        { name: 'transaction_hash', type: 'varchar' },
+        { name: 'owner_address', type: 'varchar(42)' },
+        { name: 'spender_address', type: 'varchar(42)' },
+        { name: 'amount', type: 'numeric' },
+    ],
+});
+
+export class CreateERC20TokenApprovalEvents1544131464368 implements MigrationInterface {
+    public async up(queryRunner: QueryRunner): Promise<any> {
+        await queryRunner.createTable(erc20ApprovalEvents);
+    }
+
+    public async down(queryRunner: QueryRunner): Promise<any> {
+        await queryRunner.dropTable(erc20ApprovalEvents);
+    }
+}