OCI layer blobs accumulate forever — every pull writes layers to
~/.cache/banger/oci/blobs/sha256/<hex> via go-containerregistry's
filesystem cache, and nothing ever evicts them. The cache is purely
a re-pull-avoidance (every flattened image is independent of the
blobs that sourced it), so it's a perfect candidate for an opt-in
operator-driven prune.
New surface:
* api: ImageCachePruneParams{DryRun}, ImageCachePruneResult
{BytesFreed, BlobsFreed, DryRun, CacheDir}.
* daemon: ImageService.PruneOCICache walks layout.OCICacheDir for
a (bytes, blobs) tally, then — outside dry-run — atomically
renames the cache aside, recreates it empty, and rm -rf's the
aside dir. The rename-then-rm avoids leaving the cache in a
half-removed state if a pull starts mid-prune (the in-flight
pull's open files survive the rename via standard Linux
semantics; it just sees a fresh empty cache afterwards). Missing
cache dir is treated as zero — fresh installs that have never
pulled an OCI image don't error.
* dispatch: image.cache.prune RPC (paramHandler-wrapped, mirroring
every other image RPC). Documented-methods test list updated.
* cli: `banger image cache` group with a `prune` subcommand
(--dry-run flag). Output is a single line: "freed 1.2 GiB
across 47 blob(s) in /var/cache/banger/oci" or "would free …".
formatBytes helper for the size pretty-print.
docs/oci-import.md: replaced the "Tech debt: cache eviction" bullet
with a "Cache lifecycle" section describing the new command and
the in-flight-pull caveat.
Tests: PruneOCICache covers the happy path (real prune empties the
cache, recreates an empty dir, doesn't leak the .pruning- aside),
the dry-run path (returns size, leaves blobs intact), and the
fresh-install path (cache dir absent → zero result, no error).
Smoke at JOBS=4 still green; live exercise against an empty cache
on a system install prints the expected zero summary.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Closes commit 3 of the god-service decomposition. VMService still
owned 45+ methods after the startVMLocked extraction and RPC table
landed in commits 1 and 2. Stats / ports / health / vsock-ping sit
in a corner of that surface that doesn't share any state with
lifecycle orchestration — nothing about "what's this VM's CPU
doing" belongs in the same service as Create/Start/Stop/Delete/Set.
New StatsService owns:
- GetVMStats / getVMStatsLocked / collectStats (stats collection)
- HealthVM / PingVM (vsock-agent health probe)
- PortsVM + buildVMPorts + probeWebListener + probeHTTPScheme +
dedupeVMPorts (listening-port enumeration)
- pollStats (background ticker refresh)
- stopStaleVMs (auto-stop sweep past config.AutoStopStaleAfter)
The three VMService touch-points stats genuinely needs — vmAlive,
vmHandles, the per-VM lock helpers, plus cleanupRuntime for the
stale-sweep tear-down — come in as function-typed closures, not a
*VMService pointer. StatsService has no back-reference to its
sibling. Mirrors the dependency-struct pattern WorkspaceService
already uses.
Wiring: d.stats is populated in wireServices AFTER d.vm (closures
must see a non-nil d.vm at call time). Dispatch table's four
entries (vm.stats / vm.health / vm.ping / vm.ports) now resolve
through d.stats. Background loop's pollStats / stopStaleVMs
tickers do the same. Dispatch surface from the RPC client's
perspective is byte-identical.
After this commit:
- vm_stats.go and ports.go are deleted; their content (plus the
stats-specific fields) lives in stats_service.go.
- VMService loses 12 methods. It's still the biggest service
(~30 methods, all lifecycle-supporting: handle cache, disk
provisioning, preflight, create-ops registry, lock helpers,
the lifecycle verbs themselves) but it's finally one coherent
concern instead of five.
Tests:
- TestWireServicesInstantiatesStatsService — pins that the
wiring order puts d.stats non-nil + its five closures all
populated. Prevents a silent background-loop regression.
- All existing tests that called d.vm.HealthVM / d.vm.PingVM /
d.vm.PortsVM / d.vm.collectStats were re-pointed at d.stats.
Smoke: all 21 scenarios green, including vm ports (exercises the
new PortsVM entry end-to-end) and the long-running workspace
scenarios (exercise the background stats poller implicitly).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The dispatch method was a single ~240-line switch of 34 cases, each
following the same pattern: decode params into some type P, call a
service method returning (R, error), wrap R in a result struct and
either marshalResultOrError-encode or return a raw rpc.NewError.
Adding a method was a 4-line ceremony per site, and grepping for
"methods banger speaks" meant reading the full switch.
New shape, in internal/daemon/dispatch.go:
- handler is the uniform `func(ctx, d, req) rpc.Response` type
every method dispatches through.
- paramHandler[P, R] is the generic wrapper that absorbs 28 of
the 34 cases (decode, call, marshal). No reflection — P and R
are deduced from the service-call literal, so each map entry
is a one-liner referencing a small adapter func.
- noParamHandler[R] is the decode-free variant for 6 methods
that don't carry params.
- rpcHandlers is the single source of truth for which methods
exist and which adapter they dispatch to.
- Four specials (ping, shutdown, vm.logs, vm.ssh) stay as named
`handler`-typed functions: ping/shutdown encode with raw
rpc.NewResult, vm.logs/vm.ssh need pre-service validation to
emit distinct error codes (not_found, not_running) that the
generic wrapper maps uniformly to operation_failed.
Daemon.dispatch shrinks from a 240-line switch to 11 lines:
version check, test-only handler short-circuit, table lookup,
invoke-or-unknown.
Tests:
- TestRPCHandlersMatchDocumentedMethods — keyset guard. Adding
or removing a method without updating the expected slice is a
red flag the test surfaces.
- TestRPCHandlersAllNonNil — catches nil-function registrations.
All pre-existing dispatch tests (param decode, error codes, etc.)
keep passing unchanged — the handler contract for any given
method is byte-identical from the RPC client's perspective. Smoke
(all 21 scenarios) exercises every code path end-to-end.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
