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User Story 12a - Task List Resource

Status: Expected released on 2023/02/02

It is an early morning in the heart of Tel Aviv, a CEO wakes up and heads out to WayCup, his favorite coffee shop.

He starts his day going over his emails, slack messages, updates from github, etc... But he is struggling. There are so many things he needs to do, such little time. What would he do? How will he manage all his tasks?

Well... Luckily, he is also an app developer, and when you are a developer everything can be solved with... a new app!

So he spins up VSCode with a file called task-list.w and starts writing code in a his new favorite programming language, Wing!

Your mission, if you choose to accept it, is to implement the needed pieces of the Wing compile for the first iteration of the task list app. This step includes a custom Wing resource that represents the task list, and offers an inflight API for editing the list.

bring cloud;

* Represents a cloud task list.
resource TaskList {
/** stores the tasks */
_bucket: cloud.Bucket;

/** used to create a global id */
_counter: cloud.Counter;

init() {
this._bucket = new cloud.Bucket();
this._counter = new cloud.Counter();

* Adds a task to the task list.
* @returns The ID of the new task.
inflight add_task(title: str): str {
let id = "${}";
log("adding task ${id} with title: ${title}");
this._bucket.put(id, title);
return id;

* Gets a task from the task list.
* @param id - the id of the task to return
* @returns the title of the task (optimistic)
inflight get_task(id: str): str {
return this._bucket.get(id);

* Removes a task from the list
* @throws Will throw an error if taks with id doesn't exist
* @param id - the id of the task to be removed
inflight remove_tasks(id: str): str {
log("removing task ${id}");
return id;

* Gets the tasks ids
* @returns set of task id
inflight list_task_ids(): Set<str> {
let result = MutSet<str> {};
for id in this._bucket.list() {
return result.copy();

* Find tasks with title that contains a term
* @param term - the term to search
* @returns set of task id that matches the term
inflight find_tasks_with(term: str): Array<str> {
log("find_tasks_with: ${term}");
let task_ids = this.list_task_ids();
log("found ${task_ids.size} tasks");
let output = MutArray<str>[];
for id in task_ids {
let title = this.get_task(id);
if title.contains(term) {
log("found task ${id} with title \"${title}\" with term \"${term}\"");

log("found ${output.length} tasks which match term '${term}'");
return output.copy();

// --------------------------------------------
// testing
// --------------------------------------------

let tasks = new TaskList();

new cloud.Function(inflight (s: str): str => {
tasks.add_task("clean the dishes");
let result = tasks.find_tasks_with("clean the dishes");
assert(result.length == 1);
assert("clean the dishes" == tasks.get_task(;
}) as "test: get and find task";

new cloud.Function(inflight (s: str): str => {
tasks.add_task("clean the dishes");
tasks.add_task("buy dishwasher soap");
tasks.remove_tasks(tasks.find_tasks_with("clean the").at(0));
let result = tasks.find_tasks_with("clean the dish");
assert(result.length == 0);
}) as "test: get, remove and find task";

Wing Console

During the development process of the task list app, our CEO uses Wing Console to test the application locally.

After creating the task-list.w file he starts Wing Console by running the following command and continues to develop the application side by side with the console:

wing it ./task-list.w

While Wing Console is running in the background, it watches the .w file src dir for changes, recompile the application and updates the view in real time.

In the Console, the developer can see the TaskList resource as a box. If he clicks through into this resource, he can see that it includes a Bucket and a Counter. He can see a number that represents the current value of the counter (initially 0).

Next to the TaskList resource (at the root of the app), we can see the testing cloud.Function and by clicking on the functions, tests are executed and logs and events appear in the event view. He also sees the bucket fills up with tasks as he iterates.