Session Storage

const response = await fetch("/api/items");

// Topic: Session Storage
const response = { status: 200, items: ['Svelte'] };
console.log(response.status + ' ' + response.items[0]);

// Expected Output: 200 Svelte

200 Svelte

• 1Session Storage relies on tab-scoped browser storage for temporary non-sensitive state for this session, storage lesson.
• 2Use it for ephemeral browser state and handle unavailable storage gracefully. Keep decisions specific to session, storage.
• 3Its main failure mode is Assuming storage is trusted or universally available causes failures. Do not copy assumptions from a neighboring topic into session, storage.
• 4Useful evidence is session persistence correctness measured for session, storage.

• 1Identify the owning component, store, action, route, load function, or server handler.
• 2Keep state local until multiple owners genuinely need it.
• 3Keep server secrets and validation outside browser components.
• 4Define cleanup for subscriptions, actions, timers, and requests.

• 1Test new tab, reload, close, invalid data, and private browsing. Include an assertion that directly exercises session, storage.
• 2Check initial render, assignment-driven updates, user interaction, and cleanup.
• 3Confirm keyboard and screen-reader behavior for visible UI.
• 4Measure production output only after correctness passes.

• 1Build the smallest Session Storage example.
• 2Introduce this failure: Assuming storage is trusted or universally available causes failures. Do not copy assumptions from a neighboring topic into session, storage.
• 3Correct it using this rule: Use it for ephemeral browser state and handle unavailable storage gracefully. Keep decisions specific to session, storage.
• 4Record session persistence correctness measured for session, storage before and after the change.