From d4ddd20b9ade0e68281736bfebf56f17c94c4fd2 Mon Sep 17 00:00:00 2001
From: rijkvanzanten <rijkvanzanten@me.com>
Date: Fri, 19 Jun 2020 11:14:40 -0400
Subject: [PATCH] Add extensions service and routes

---
 .env.example               |  2 ++
 src/app.ts                 |  2 ++
 src/error.ts               |  8 ++++++--
 src/routes/extensions.ts   | 28 ++++++++++++++++++++++++++++
 src/services/extensions.ts | 18 ++++++++++++++++++
 src/utils/list-folders.ts  | 25 +++++++++++++++++++++++++
 6 files changed, 81 insertions(+), 2 deletions(-)
 create mode 100644 src/routes/extensions.ts
 create mode 100644 src/services/extensions.ts
 create mode 100644 src/utils/list-folders.ts

diff --git a/.env.example b/.env.example
index c3da0aec83..aa23c26ca3 100644
--- a/.env.example
+++ b/.env.example
@@ -6,3 +6,5 @@ DB_PORT=5432
 DB_NAME="directus"
 DB_USER="postgres"
 DB_PASSWORD="psql1234"
+
+EXTENSIONS_PATH="./extensions"
diff --git a/src/app.ts b/src/app.ts
index 07be3a4975..7244dd3826 100644
--- a/src/app.ts
+++ b/src/app.ts
@@ -13,6 +13,7 @@ import relationsRouter from './routes/relations';
 import revisionsRouter from './routes/revisions';
 import rolesRouter from './routes/roles';
 import usersRouter from './routes/users';
+import extensionsRouter from './routes/extensions';
 import notFoundHandler from './routes/not-found';
 
 const app = express()
@@ -27,6 +28,7 @@ const app = express()
 	.use('/revisions', revisionsRouter)
 	.use('/roles', rolesRouter)
 	.use('/users', usersRouter)
+	.use('/extensions', extensionsRouter)
 	.use(notFoundHandler)
 	.use(errorHandler);
 
diff --git a/src/error.ts b/src/error.ts
index c962d09229..5dc3242008 100644
--- a/src/error.ts
+++ b/src/error.ts
@@ -5,12 +5,16 @@ export enum ErrorCode {
 	NOT_FOUND = 'NOT_FOUND',
 	FIELD_NOT_FOUND = 'FIELD_NOT_FOUND',
 	INTERNAL_SERVER_ERROR = 'INTERNAL_SERVER_ERROR',
+	ENOENT = 'ENOENT',
+	EXTENSION_ILLEGAL_TYPE = 'EXTENSION_ILLEGAL_TYPE',
 }
 
 enum HTTPStatus {
 	NOT_FOUND = 404,
 	FIELD_NOT_FOUND = 400,
 	INTERNAL_SERVER_ERROR = 500,
+	ENOENT = 501,
+	EXTENSION_ILLEGAL_TYPE = 400,
 }
 
 export const errorHandler: ErrorRequestHandler = (error: APIError | Error, req, res, next) => {
@@ -38,12 +42,12 @@ export const errorHandler: ErrorRequestHandler = (error: APIError | Error, req,
 			},
 		};
 
-		if ((process.env.NODE_ENV = 'development')) {
+		if (process.env.NODE_ENV === 'development') {
 			response.error.message = error.message;
 		}
 	}
 
-	if ((process.env.NODE_ENV = 'development')) {
+	if (process.env.NODE_ENV === 'development') {
 		response.error.stack = error.stack;
 	}
 
diff --git a/src/routes/extensions.ts b/src/routes/extensions.ts
new file mode 100644
index 0000000000..1e973bfcaf
--- /dev/null
+++ b/src/routes/extensions.ts
@@ -0,0 +1,28 @@
+import { Router } from 'express';
+import asyncHandler from 'express-async-handler';
+import * as ExtensionsService from '../services/extensions';
+import APIError, { ErrorCode } from '../error';
+
+const router = Router();
+
+router.get(
+	'/:type',
+	asyncHandler(async (req, res) => {
+		const typeAllowList = ['interfaces', 'layouts', 'displays', 'modules'];
+
+		if (typeAllowList.includes(req.params.type) === false) {
+			throw new APIError(
+				ErrorCode.EXTENSION_ILLEGAL_TYPE,
+				`${req.params.type} is not an extension type.`
+			);
+		}
+
+		const interfaces = await ExtensionsService.listExtensions(req.params.type);
+
+		return res.json({
+			data: interfaces,
+		});
+	})
+);
+
+export default router;
diff --git a/src/services/extensions.ts b/src/services/extensions.ts
new file mode 100644
index 0000000000..edde0634b4
--- /dev/null
+++ b/src/services/extensions.ts
@@ -0,0 +1,18 @@
+import listFolders from '../utils/list-folders';
+import path from 'path';
+import APIError, { ErrorCode } from '../error';
+
+export async function listExtensions(type: string) {
+	const extensionsPath = process.env.EXTENSIONS_PATH;
+	const location = path.join(extensionsPath, type);
+
+	try {
+		return await listFolders(location);
+	} catch (err) {
+		if (err.code === 'ENOENT') {
+			throw new APIError(ErrorCode.ENOENT, `The ${type} folder doesn't exist.`);
+		}
+
+		throw err;
+	}
+}
diff --git a/src/utils/list-folders.ts b/src/utils/list-folders.ts
new file mode 100644
index 0000000000..705d9b181a
--- /dev/null
+++ b/src/utils/list-folders.ts
@@ -0,0 +1,25 @@
+import fs from 'fs';
+import path from 'path';
+import { promisify } from 'util';
+import APIError, { ErrorCode } from '../error';
+
+const readdir = promisify(fs.readdir);
+const stat = promisify(fs.stat);
+
+export default async function listFolders(location: string) {
+	const fullPath = path.join(process.cwd(), location);
+	const files = await readdir(fullPath);
+
+	const directories: string[] = [];
+
+	for (const file of files) {
+		const filePath = path.join(fullPath, file);
+		const stats = await stat(filePath);
+
+		if (stats.isDirectory()) {
+			directories.push(file);
+		}
+	}
+
+	return directories;
+}