Abstract out DataContainer into interface

src/http/lifecycle/Request.ts

@@ -39,11 +39,18 @@ export interface HTTPSourceAddress {
     port: number;
 }
 
+/**
+ * Interface describing a container that holds user input data.
+ */
+export interface DataContainer {
+    input(key?: string): any
+}
+
 /**
  * A class that represents an HTTP request from a client.
  */
 @Injectable()
-export class Request extends ScopedContainer {
+export class Request extends ScopedContainer implements DataContainer {
 
     /** The cookie manager for the request. */
     public readonly cookies: HTTPCookieJar;
@@ -170,7 +177,15 @@ export class Request extends ScopedContainer {
      * Get the value of an input field on the request. Spans multiple input sources.
      * @param key
      */
-    public input(key: string) {
+    public input(key?: string) {
+        if ( !key ) {
+            return {
+                ...this.parsedInput,
+                ...this.query,
+                ...this.uploadedFiles,
+            }
+        }
+
         if ( key in this.parsedInput ) {
             return this.parsedInput[key]
         }