add onPreInit log

Author: saikojosh

gatsby-node.js

@@ -1 +1,4 @@
-exports.sourceNodes = require(`./dist/src/main`).sourceNodes;
+const plugin = require(`./dist/src/main`);
+
+exports.onPreInit = plugin.onPreInit;
+exports.sourceNodes = plugin.sourceNodes;

src/gatsby/onPreInit.ts

@@ -0,0 +1,12 @@
+/**
+ * @file On pre init.
+ */
+
+import pkg from '../../package.json';
+
+/**
+ * Outputs a log on initialisation.
+ */
+export function onPreInit(): void {
+	console.log(`${pkg.name} @ ${pkg.version} loaded`); // tslint:disable-line:no-console
+}

src/main.ts

@@ -4,4 +4,5 @@
 
 export * from './lib/definitions';
 
+export { onPreInit } from './gatsby/onPreInit';
 export { sourceNodes } from './gatsby/sourceNodes';