Re-running scripts

Sparke keeps the JS context alive across swaps. Re-run page code with data-sparke-rerun or an event.

Sparke keeps the JS context alive across navigations, so scripts in fetched pages don't re-run automatically. Most of the time that's exactly what you want. When a page needs its own script to run on each visit, mark it.

data-sparke-rerun

Mark a page's own script with data-sparke-rerun and Sparke runs it on each swap. It must live in the swapped region (inside <main>, or anywhere in <body>).

On each swaphtml

<main>
  <canvas id="chart"></canvas>

  <!-- re-runs every time this page is swapped in -->
  <script data-sparke-rerun>
    initChart(document.getElementById("chart"));
  </script>

  <!-- run only on the first visit, then never again -->
  <script data-sparke-rerun="once" src="/widgets.js"></script>
</main>

A marked script re-runs in the same live context, so keep it idempotent: avoid top-level const/let/class, and clean up old listeners and timers.

Site-wide logic

For things that run on every page (analytics, re-binding widgets), listen once instead of repeating code on every page:

Listen oncejs

window.addEventListener("sparke:after-swap", (e) => {
  initMyWidgets();
  // e.detail.from / e.detail.to are the URLs
});

See Events for the full set, and Migrating a site for an init checklist.