Simple functions for querying the SW cache

cacheTools.js

// Simple functions for querying the SW cache.

// Only approximate! (1) Only includes bodies. (2) Can't count opaque resources.

function cacheDump(c) {
  return c.keys().then(a => {
    return Promise.all(a.map(req =>
      c.match(req).then(res => res.clone().blob().then(b => [req.url, b.size]))
    )).then(a => new Map(a));
  });
}

function cacheSize(c) {
  return c.keys().then(a => {
    return Promise.all(
      a.map(req => c.match(req).then(res => res.clone().blob().then(b => b.size)))
    ).then(a => a.reduce((acc, n) => acc + n, 0));
  });
}

function cachesDump() {
  return caches.keys().then(a => {
    return Promise.all(a.map(n => {
      return caches.open(n).then(c => cacheDump(c)).then(v => [n, v]);
    })).then(a => new Map(a));
  });
}

function cachesSize() {
  return caches.keys().then(a => {
    return Promise.all(
      a.map(n => caches.open(n).then(c => cacheSize(c)))
    ).then(a => a.reduce((acc, n) => acc + n, 0));
  });
}

function cachesStats() {
  return caches.keys().then(a => {
    return Promise.all(
      a.map(n => caches.open(n).then(c => {
        return Promise.all([cacheDump(c), cacheSize(c)]).then(v => {
          return new Map([
            ["entries", [...v[0].entries()].sort((a, b) => b[1] - a[1])],
            ["size", v[1]]
          ]);
        }).then(v => [n, v]);
      }))
    ).then(a => new Map(a));
  });
}

cachesSize().then(console.log); // total size of all caches