Add support for middleware

src/service/Middlewares.ts

@@ -0,0 +1,20 @@
+import {CanonicalStatic} from "./CanonicalStatic";
+import {Singleton, Instantiable} from "@extollo/di";
+import {CanonicalDefinition} from "./Canonical";
+import {Middleware} from "../http/routing/Middleware";
+
+@Singleton()
+export class Middlewares extends CanonicalStatic<Instantiable<Middleware>, Middleware> {
+    protected appPath = ['http', 'middlewares']
+    protected canonicalItem = 'middleware'
+    protected suffix = '.middleware.js'
+
+    public async initCanonicalItem(definition: CanonicalDefinition) {
+        const item = await super.initCanonicalItem(definition)
+        if ( !(item.prototype instanceof Middleware) ) {
+            throw new TypeError(`Invalid middleware definition: ${definition.originalName}. Controllers must extend from @extollo/lib.http.routing.Middleware.`)
+        }
+
+        return item
+    }
+}