Add firebase user auth middleware

src/app/http/middlewares/api/FirebaseUserOnly.middleware.ts

@@ -0,0 +1,42 @@
+import {Config, error, Middleware} from "@extollo/lib"
+import {Inject, Injectable} from "@extollo/di"
+import {FirebaseUnit} from "../../../units/FirebaseUnit"
+import {HTTPStatus} from "@extollo/util"
+
+/**
+ * FirebaseUserOnly Middleware
+ * --------------------------------------------
+ * Authenticates the request based on the user ID token.
+ */
+@Injectable()
+export class FirebaseUserOnly extends Middleware {
+    @Inject()
+    protected readonly firebase!: FirebaseUnit
+
+    @Inject()
+    protected readonly config!: Config
+
+    get headerName(): string {
+        return String(this.config.get('app.firebase.api_auth_header'))
+    }
+
+    getAuthHeader(): string {
+        const tokens = this.request.getHeader(this.headerName)
+        if ( Array.isArray(tokens) ) return tokens[0]
+        return String(tokens)
+    }
+
+    public async apply() {
+        const token = this.getAuthHeader()
+
+        if ( !token ) {
+            return error(`Missing ${this.headerName} header`, HTTPStatus.UNAUTHORIZED, 'json')
+        }
+
+        try {
+            await this.firebase.get().auth().verifyIdToken(token)
+        } catch (e) {
+            return error('Invalid API token.', HTTPStatus.UNAUTHORIZED, 'json')
+        }
+    }
+}