Add a "download my answers" button

Adds a button that, when clicked, gathers every question() and student_info() answer currently on the page – each already saved to the browser's localStorage as the reader worked through the tutorial – into a single readable JSON file and downloads it. This happens entirely in the reader's browser; there is no server to submit to, so this is meant for a reader to save and turn in themselves (e.g. attach to an email or upload to an LMS).

Usage

download_answers_button(
  filename_prefix = "learnr2-answers",
  label = "Download My Answers"
)

Arguments

filename_prefix

Prefix for the downloaded file's name. Defaults to "learnr2-answers".

label

Button label. Defaults to "Download My Answers".

Value

A learnr2_download_button object, printed as an interactive HTML button.

Details

The download's exercises array also includes every {webr} code exercise's current code, under the same condition quarto-live itself requires to keep a record of it at all: #| persist: true (already the convention every bundled tutorial follows). An exercise without persist: true has no saved copy of the reader's code anywhere – learnr2 included – so it can't appear in the download; this is a structural limit of quarto-live's own editor, not something download_answers_button() chooses to skip.

The download includes a metadata block (timestamp, timezone, browser info, and a random per-device id persisted across the reader's visits) and a SHA-256 integrity hash over the content. Check a downloaded file with verify_submission(). This is tamper-evidence, not proof of identity: since everything runs in the reader's own browser with no server-held secret, a technical reader could reproduce the hash themselves. What it reliably catches is editing the file afterward (e.g. changing a wrong answer to a right one before turning it in).

Examples

download_answers_button()