feat!: add cache service v2, add toolkit patches (#1110)

Serves `github.actions.results.api.v1.CacheService` next to the v1 cache API, sharing its store, plus the subset of the Azure blob protocol the toolkit uploads with. On by default via `cache.v2`, and works with `external_server`.

Clients reach it through two edits in the action's own bundle: the GHES check is opened, and the cache service URL is taken from `ACTIONS_CACHE_URL`.

The same GHES check is what makes the stock `actions/upload-artifact` and `download-artifact` abort on Gitea. Opening it makes them work without the `gitea-upload-artifact` fork, from `upload-artifact@v4.4.0` on.

Verified against 118 real bundles, every major version of 16 actions: 92 patched, the rest deliberately left alone, and every patched bundle checked with `node --check`. Also end to end against pinned `actions/cache@v6.1.0` with an unreachable results URL, so only the patch can make the cache work.

---------

Co-authored-by: silverwind <me@silverwind.io>
Co-authored-by: bircni <me@silverwind.io>
Reviewed-on: https://gitea.com/gitea/runner/pulls/1110
Reviewed-by: silverwind <2021+silverwind@noreply.gitea.com>

internal/pkg/config/config.example.yaml

@@ -155,6 +155,11 @@ cache:
   # A moved tag (e.g. a re-tagged "v6") or an updated branch stays at the cached commit
   # until its cache entry expires or is manually removed.
   offline_mode: false
+  # Serve the actions cache service v2 API, used by actions/cache@v4.2 and later. Those actions
+  # refuse any host they do not take for GitHub, so reaching it means editing that check out of
+  # the action's own bundle, keeping the untouched copy beside it. The same edit lets the stock
+  # upload-artifact and download-artifact work here. A bundle that does not match is left alone.
+  v2: true
 
 container:
   # Specifies the network to which the container will connect.

internal/pkg/config/config.go

@@ -74,6 +74,7 @@ type Cache struct {
 	ExternalSecret     string `yaml:"external_secret"`      // ExternalSecret is a shared secret between this runner and an external gitea-runner cache-server, enabling per-job ACTIONS_RUNTIME_TOKEN authentication and repo scoping over the network. Required whenever ExternalServer is set; ExternalSecretFile is the alternative way to provide it.
 	ExternalSecretFile string `yaml:"external_secret_file"` // ExternalSecretFile is the path to a file holding the ExternalSecret value, so the secret can be mounted instead of stored in the config file. LoadDefault reads it into ExternalSecret; setting both is an error.
 	OfflineMode        bool   `yaml:"offline_mode"`         // OfflineMode reuses a cached action without fetching from the remote; a moved tag or branch stays at the cached commit until the cache entry is removed.
+	V2                 *bool  `yaml:"v2"`                   // V2 serves the actions cache service v2 API to jobs, used by actions/cache@v4.2 and later, and edits the action bundles that would otherwise refuse it. Unset means enabled.
 }
 
 // Container represents the configuration for the container.

internal/pkg/config/config_test.go

@@ -347,3 +347,13 @@ cache:
 	require.Error(t, err)
 	assert.Contains(t, err.Error(), "contains no secret")
 }
+
+// The shipped example must parse, and every key in it must be one the config knows.
+func TestLoadDefault_ExampleConfigParses(t *testing.T) {
+	hook := test.NewGlobal()
+	defer hook.Reset()
+
+	_, err := LoadDefault("config.example.yaml")
+	require.NoError(t, err)
+	assert.Empty(t, hook.AllEntries())
+}