fix: Fix typings for @sendgrid/eventwebhook (#1180)

Author: igrayson

packages/eventwebhook/index.d.ts

@@ -1,6 +1,3 @@
-import {EventWebhook, EventWebhookHeader} = require('./src/eventwebhook');
+import EventWebhook = require('./src/eventwebhook');
 
-export {
-    EventWebhook,
-    EventWebhookHeader
-};
+export = EventWebhook;

packages/eventwebhook/src/eventwebhook.d.ts

@@ -19,4 +19,16 @@ declare class EventWebhook {
     verifySignature(publicKey: PublicKey, payload: string|Buffer, signature: string, timestamp: string): boolean;
 }
 
-export = EventWebhook;
+/*
+ * This class lists headers that get posted to the webhook. Read the docs for
+ * more details: https://sendgrid.com/docs/for-developers/tracking-events/event
+ */
+declare class EventWebhookHeader {
+    static SIGNATURE(): string;
+    static TIMESTAMP(): string
+}
+
+export {
+    EventWebhook,
+    EventWebhookHeader,
+};

test/typescript/eventwebhook.ts

@@ -1,4 +1,4 @@
-import EventWebhook = require('@sendgrid/eventwebhook');
+import { EventWebhook } from '@sendgrid/eventwebhook';
 
 var ew = new EventWebhook();
 const PUBLIC_KEY = "MFkwEwYHKoZIzj0CAQYIKoZIzj0DAQcDQgAEEDr2LjtURuePQzplybdC+u4CwrqDqBaWjcMMsTbhdbcwHBcepxo7yAQGhHPTnlvFYPAZFceEu/1FwCM/QmGUhA==";