Skip to main content

Tracking several projects

One deployment already serves many sites: every counter is keyed under a site segment, each site has its own token, and prune walks each one separately. This page is the reasoning; the hands-on flow, with a check after every step, lives at /help on your own collector.

One site id per project​

GitHub Pages projects usually share a host — user.github.io/proj-a, user.github.io/proj-b. Host-based resolution cannot separate those, so each project gets its own id and declares it on the tag:

<script defer src="https://<collector>/s.js" data-site="proj-a"></script>
SITES="proj-a,proj-b,acme:acme.dev"
STATS_TOKEN_PROJ_A=…
STATS_TOKEN_PROJ_B=…

A bare id in SITES is selectable only through ?s= / data-site; id:host also maps a custom domain, and on such a domain data-site is optional because the Host already answers the question.

There is deliberately no path-prefix routing (why).

Adding one is an env edit, not a deploy​

Editing environment variables on Deno Deploy creates a new revision by itself — no git push and no code change. That is why the site allowlist stays in SITES rather than in a runtime registry: a registry would trade a two-field form for a mutation endpoint, stored token hashes, and a cache-invalidation story across isolates.

The write budget is shared, not per site​

The whole deployment carries about 25K pageviews/month on the free tier, split across every site on it. Eight projects at an even split is ~3K pageviews each. Numbers and the reasoning: Design notes.

Two consequences worth knowing before you add the fifth project:

  • Adding a dimension costs a write unit on every pageview of every site.
  • One project going viral spends the shared budget. There is no per-site cap today; watch the pageview counts on the dashboard if that becomes a risk.

deno task admin -- size --db <uuid> gives you the per-site split of what is actually stored.

Reading them back​

STATS_TOKEN is the admin token: it reads any site and is the only token allowed on /sites, which is what fills the dashboard's site picker. A per-site STATS_TOKEN_<ID> reads exactly one site — hand it out and the holder cannot see any other project. The check is against the resolved site, never against the set of all tokens.