zwave-js / zwave-js-ui / 29833164293

12%

push

github

ci: stop PR builds from filling the Actions cache (#4752)

## Problem

The repository's Actions cache is over its 10 GB cap and permanently
evicting entries:

```
active_caches_size_in_bytes: 10,695,169,546   (cap 10 GB)
active_caches_count:         597
```

Broken down by ref, almost all of it is unreachable by anything:

| ref | entries | size |
|---|---:|---:|
| `refs/pull/4727/merge` | 124 | 1387 MB |
| `refs/pull/4751/merge` | 104 | 1284 MB |
| `refs/pull/4734/merge` | 62 | 1237 MB |
| `refs/pull/4732/merge` | 62 | 1237 MB |
| `refs/pull/4733/merge` | 57 | 1229 MB |
| `refs/pull/4735/merge` | 59 | 1189 MB |
| `refs/pull/4741/merge` | 59 | 1189 MB |
| `refs/pull/4742/merge` | 57 | 1185 MB |
| **`refs/heads/master`** | **16** | **262 MB** |

8.3 GB of that is buildkit blobs written by `docker-test.yml`'s
`cache-to: type=gha,mode=max`, which runs on every pull request.

A cache saved on a PR ref **can only be read back by that same PR**. So
each PR wrote roughly a gigabyte no other PR and no master build could
ever use, and it stayed until eviction. `docker-test.yml` also used the
unscoped default scope while the release builds use `scope=zwave-js-ui`,
so it never shared with them either: every new PR started cold and every
new PR made things worse.

Being over the cap, GitHub evicts least-recently-used entries. The
visible casualty is the docs answer bot from #4743, whose 1–2 MB indexes
vanish within hours. Direct evidence — the nightly `docs-embeddings` run
missed the cache **it had saved itself the previous morning under the
identical key**:

```
2026-07-17T05:58:52Z  Cache not found for input keys: docs-embeddings-v2-4d1349a..., docs-embeddings-v2-
2026-07-17T05:59:11Z  Cache saved with key:           docs-embeddings-v2-4d1349a...
```

## Changes

**`docker-test.yml` — read the cache, don't write it.** `cache-to` is
dropped and `cache-from` now points at `scope=zwave-js-ui`, the scope
the release builds populate on master. PR builds stop writing... (continued)

493 of 4531 branches covered (10.88%)

Branch coverage included in aggregate %.

938 of 7002 relevant lines covered (13.4%)

2.08 hits per line