Create Task Form - End to End Build the first real browser form against the secured NestJS API
Phase 21 - Forms with React Hook Form + Zod Volume 06 - Professional Frontend
Build CreateTaskForm The create form starts with empty defaults, validates locally, maps UI values to the API contract, acquires a current Supabase access token, submits to NestJS, and then refreshes the Task list after success.
const defaultValues: TaskFormValues = { title: "", description: "", priority: "MEDIUM", dueAtLocal: "", };
Map UI values to API input function toCreateTaskInput( projectId: string, values: TaskFormValues, ) { return { projectId, title: values.title, description: values.description || null, priority: values.priority, dueAt: values.dueAtLocal ? new Date(values.dueAtLocal).toISOString() : null, }; }
Submission const onSubmit = handleSubmit(async (values) => { clearErrors("root.server");
try { const input = toCreateTaskInput(projectId, values); await createTaskFromBrowser(input); reset(defaultValues); router.push("/tasks"); router.refresh(); } catch (error) { setError("root.server", { message: messageForApiError(error), }); } });
zodResolver validates UI shape
Prevent duplicate submissions Use isSubmitting to disable the submit button while the promise returned by the submit handler is pending. Do not maintain a second manual loading flag for the same form operation unless it represents different state.
<button type="submit" disabled={isSubmitting}>
{isSubmitting ? "Creating..." : "Create task"}
</button>Create Task Form End to End matters because it changes a real boundary in TaskFlow. The goal is to understand the inputs, owner, observable output, and failure modes before adding more abstraction.
Restate the goal of “Create Task Form End to End” as one observable behavior. Write the success signal before touching code.
Trace the boundary map: user input → form state → Zod validation → mutation → server feedback. Mark the one boundary this lesson changes.
Inspect the current repository state and record the exact files, route, table, or runtime involved. Avoid creating an abstraction before you can name the existing owner.
Implement the smallest vertical slice. Add one coherent change, run the narrowest verification command, and read the output before continuing.
Connect the slice to TaskFlow’s phase artifact: Create/edit task forms with shared field rules, accessible errors, async submission, server-error mapping, and reset behavior.. Verify behavior from the outside as a user or API client would.
Create one controlled failure that is safe to reproduce. Predict the symptom first, capture evidence, locate the earliest broken boundary, then fix only that cause.
Close the reference and rebuild or explain the core change from memory. Record what you would monitor or test before trusting the same change in production.
const form = useForm<CreateTaskInput>({
resolver: zodResolver(CreateTaskSchema),
defaultValues: { title: "", priority: "MEDIUM" },
});
const onSubmit = form.handleSubmit(values => mutate(values));Do not copy this as a finished answer. Predict what each boundary does, type the smallest useful slice, run it, then compare the result with your prediction.
Return to the nearest observable boundary: input, network, process log, database, or rendered UI. Compare actual evidence with the predicted path.
Change one variable at a time and reproduce the original failure after the fix; otherwise you have correlation, not diagnosis.
Without copying the final source, create a second small scenario that applies “Create Task Form End to End” to a different TaskFlow resource or input. Write the acceptance criteria first, implement it, and provide the evidence that each criterion is satisfied.
Send data through the mutation layer and map server validation/conflict errors back to fields or form-level feedback.
Use the smallest change that demonstrates this lesson. Stop after it works and capture evidence.Duplicating server data into form state without reset strategy
Predict the symptom before causing the failure. Then locate the earliest boundary where reality diverges from expectation.Why does this responsibility live here, what input does it trust, what output proves success, and what would go wrong if another layer owned it?
If your explanation is vague, repeat the boundary trace before moving on.Close the reference. Reproduce the core idea from memory or explain the exact request/data flow aloud. Then check your diff or notes for accidental shortcuts that bypass validation, authorization, error handling, or verification earned in earlier phases.