diff --git a/src/entities/RequestHandler.ts b/src/entities/RequestHandler.ts
index 3277e0a..b297eab 100644
--- a/src/entities/RequestHandler.ts
+++ b/src/entities/RequestHandler.ts
@@ -6,6 +6,7 @@ import { AccountHelper } from "../helpers/AccountHelper";
 import { UploadedFile } from "express-fileupload";
 import { prepareFileCreation, generateNewUserDataFileName, pathUserData } from "../utils/UserDataUtils";
 import * as sharp from 'sharp';
+import { UserHelper } from "../helpers/UserHelper";
 
 /**
  * Response to a request
@@ -162,16 +163,39 @@ export class RequestHandler {
 	 * Get a boolean included in the request
 	 * 
 	 * @param name The name of the POST field
+	 * @param fallback Fallback value to use if the value is not
+	 * found in the request
 	 */
-	public postBool(name: string) : boolean {
+	public postBool(name: string, fallback ?: boolean) : boolean {
 		const param = this.getPostParam(name);
 
-		if(param == undefined)
+		if(param == undefined) {
+			if(fallback != undefined)
+				return fallback;
+
 			this.error(400, "Missing boolean '" + name + "' in the request!");
+		}
 		
 		return param === "true" || param === true;
 	}
 
+	/**
+	 * Get the ID of a user specified in a POST request
+	 * 
+	 * @param name Name of the POST field
+	 */
+	public async postUserId(name: string) : Promise<number> {
+		const userID = this.postInt(name);
+
+		if(userID < 1)
+			this.error(400, "Invalid user ID specified in '" + name +"'!");
+		
+		if(!await UserHelper.Exists(userID))
+			this.error(404, "User with ID " + userID + " not found!");
+		
+		return userID;
+	}
+
 	/**
 	 * Get information about an uploaded file
 	 *