Commit Graph

4 Commits

Author SHA1 Message Date
Pim van Pelt
1191b3d994 Frontend aggregate state: SPA-side derive + checker fixes
The web UI showed the wrong up/down state for frontends whose pool
composition had been touched by a mix of runtime disable/enable and
weight changes: a frontend with every backend at effective_weight=0
would still display "up", while a sibling frontend with a serving
fallback backend would display "down". Two independent bugs, each
fixed on its own layer.

On the fast path (healthCheckEqual returns true), Reload did
`w.entry = b`, blindly replacing the runtime worker entry with the
fresh YAML record. YAML's default for Enabled is true, so any
backend the operator had runtime-disabled would have its Enabled
flag silently reset while the worker's backend.State stayed at
StateDisabled. Subsequent EnableBackend calls then early-returned
on `if w.entry.Enabled` and never transitioned the state machine
— the CLI reported "enabled, state is 'disabled'" and the backend
was permanently stuck.

Fix: preserve w.entry.Enabled across the fast-path replacement.

    runtimeEnabled := w.entry.Enabled
    w.entry = b
    w.entry.Enabled = runtimeEnabled

Runtime operator state now outlives config reloads. On the worker-
restart path (different health check) the new worker is
structurally fresh and the YAML's Enabled is still authoritative.

Both methods used `w.entry.Enabled` as their idempotency check,
which meant a stuck `Enabled=true, State=disabled` combo couldn't
be repaired even after the Reload fix (existing bad state had to
survive the upgrade). Switched both methods to key on
`w.backend.State`:

 - DisableBackend: if state == StateDisabled, sync the flag but
   don't emit a redundant transition; otherwise do the full
   state transition + flag flip + worker cancel.
 - EnableBackend: if state != StateDisabled, sync the flag but
   don't emit a redundant transition; otherwise do the full
   transition + flag flip + probe-goroutine restart.

Either method will now unstick any inconsistency between the
flag and the state machine — future drift from a panic, a new
code path we haven't thought of, or existing already-stuck
backends from before this commit are all repaired on the next
enable/disable call.

Changing a backend's weight can flip a frontend between up and
down (e.g. zeroing the last non-zero-weighted backend in the
active pool), but SetFrontendPoolBackendWeight never called
updateFrontendState, so the checker's cached frontend state
would drift from reality until the next genuine backend
transition happened to trigger a recompute. The symptom was
"show frontends nginx-ip4-http" reporting up even with every
effective_weight=0.

Fix: call c.updateFrontendState(frontendName, fe) after the
weight mutation, under the same lock. The recompute emits a
FrontendEvent transition if the aggregate flipped, so any
WatchEvents consumer picks up the change live.

stores/state.ts recomputeEffectiveWeights is renamed and
extended to recomputeDerivedState, which now also writes
fe.state using the same rule as health.ComputeFrontendState:
unknown if no backends or all unknown, up if any effective
weight > 0, down otherwise. Called from every mutation path
(replaceAll, replaceSnapshot, applyBackendTransition,
applyConfiguredWeight) so the SPA is authoritative for *display*
state and doesn't inherit any staleness the server's cached
frontendStates map might have.

applyFrontendTransition is now a no-op for the state field —
the server's `to` value is no longer trusted because
recomputeDerivedState walks the local backends array on every
update and produces a fresh, correct answer. The reducer is kept
as a named function so sse.ts's dispatch table still has a
landing spot for "frontend" events (they still feed the
DebugPanel via pushEvent); the empty body is deliberate, not a
bug — a comment at the top spells it out.
2026-04-12 23:50:26 +02:00
Pim van Pelt
4347bb9b05 Bug fixes, config validation, SPA tightening, set-weight UI
This session covers three distinct arcs: correctness bug fixes in the
VPP sync path and frontend reducers, new config validation, and a
large polish pass on the web frontend (tighter layout, backend kebab
dialogs, live grouped-table, live config-reload re-sync).

 - encap for a VIP is now derived from the backend address family,
   not the VIP's. A v6 VIP with v4 backends is programmed as IP6_GRE4
   (not the buggy IP6_GRE6), matching the VPP LB plugin's
   requirement that encap reflects the tunnel inner family. desiredVIP
   gained an Encap field populated in desiredFromFrontend.
 - ActivePoolIndex now requires at least one backend in a pool to be
   BOTH in StateUp AND pb.Weight>0 before the pool counts as active.
   Previously a primary pool with every backend manually zeroed would
   still win over a fallback with weight=100, so fallback traffic
   never materialized. New TestActivePoolIndexWeightedFailover table
   pins the rule in five subcases.
 - SyncLBStateVIP gained a flushAddress parameter threaded through
   reconcileVIP; it forces flush=true on the setASWeight call for a
   specific backend regardless of the usual 0→N heuristic. Wires up
   the explicit [flush] knob the CLI exposes.

 - convertFrontend already enforced that backends within one frontend
   share a family. New cross-frontend pass validateVIPFamilyConsistency
   rejects configs where two frontends share a VIP address but carry
   backends in different families — VPP's LB plugin requires every
   VIP on a prefix to have the same encap type, so such a config
   would fail at lb_add_del_vip_v2 time with VNET_API_ERROR_INVALID
   _ARGUMENT (-73). Catching it at config load turns a silent
   runtime failure into a clear startup error.
 - Two new TestValidationErrors cases pin the behavior: mismatched
   families reject, same-family frontends on one VIP address allowed.

 - Proto adds `bool flush = 5` to SetWeightRequest. The RPC now
   drives a VIP sync immediately after mutating config (fixing the
   latent "weight change only takes effect at the next 30s periodic
   reconcile" gap), passing flushAddress = backend IP when req.Flush
   is true.
 - maglevc grows an optional [flush] token: `set frontend F pool P
   backend B weight N [flush]`. Implementation uses two Run closures
   (runSetFrontendPoolBackendWeight and -Flush) because the tree
   walker only puts slot tokens in args — literal keywords like
   `flush` advance the node but don't appear in the arg list.
 - docs/user-guide.md updated with the [flush] optional and a
   three-paragraph explainer of the graceful-drain vs. flush
   semantics at the VPP level.

 - checker.ListFrontends now sorts alphabetically to match the
   existing sort in ListBackends / ListHealthChecks — RPC responses
   no longer shuffle VIPs per call. cmd/frontend/client.go also
   sorts defensively in refreshAll so an old maglevd build renders
   alphabetically too.
 - backendFromProto was returning out.Transitions[n-1] as the
   LastTransition, but maglevd stores (and the proto carries)
   transitions newest-first, so [n-1] was actually the oldest.
   Reverse on read, which normalizes the client's Transitions slice
   to oldest-first and makes [n-1] genuinely the newest. LastTransition
   now points at the actual latest transition record.
 - applyBackendTransition (Go and TS) derives Enabled = state!="disabled"
   so the two fields stay in lockstep — closed a drift window where
   a recently re-enabled backend still rendered with a stuck
   [disabled] tag. The tag was later removed entirely since state
   and enabled carry the same information.

 - Layout tightened substantially: "FRONTENDS" panel header removed,
   zippy-summary and zippy-body paddings cut, backend-table row
   padding dropped to 2px, per-pool <h3> removed. Pools now live in
   a single consolidated table per frontend with a dedicated "pool"
   column that shows the pool name only on the first row of each
   group — classic grouped-table layout, maximally dense.
 - Description moved inline into the Zippy summary as muted italic
   text, freeing a vertical line per frontend card.
 - formatVIPAddress() helper renders IPv6 VIPs as [addr]:port and
   IPv4 as addr:port, matching RFC 3986 authority syntax.
 - Pools with effective_weight=0 on every backend (standby
   fallbacks, fully-drained primaries) render at opacity 0.35 on
   their non-actions cells; the kebab column stays at full contrast
   because its menu is still fully functional on standby backends.
 - Config-reload propagation: a maglevd config-reload-done log
   event triggers triggerConfigResync() on the frontend side —
   refreshAll() runs off the event-dispatch goroutine, then a
   BrowserEvent{Type:"resync"} is published through the broker.
   writeEvent emits type="resync" as a named SSE frame so the
   SPA's existing addEventListener("resync") handler picks it up
   and calls fetchAllState → replaceAll.
 - recomputeEffectiveWeights in stores/state.ts mirrors the
   server-side health.EffectiveWeights logic so the SPA keeps
   pool.effective_weight correct the moment a backend transitions,
   without waiting for the 30s refresh. Fixed a nasty bug where
   applyBackendEffectiveWeight wrote VIP-scoped vpp-lb-sync-as-*
   event weights into every frontend sharing the backend,
   corrupting frontends with different per-pool configured weights.
   The old log-event reducer was removed; applyConfiguredWeight is
   the narrower replacement used by the kebab set-weight flow.
 - applyBackendTransition calls recomputeEffectiveWeights after
   state updates so pool-failover transitions (primary ⇌ fallback)
   reflect instantly in the UI.

 - Confirmation dialogs via a new Modal primitive
   (Portal-mounted to document.body, escape/click-outside close,
   click-outside debounced on mousedown so mid-row-text-selection
   drags don't dismiss).
 - pause/resume/enable/disable each show a Modal with a consequence
   paragraph explaining what hits live traffic ("will keep existing
   flows", "will flush VPP's flow table", etc.). The disable commit
   button is styled btn-danger red.
 - set-weight action shows a Modal with a range slider (0-100,
   seeded from the current configured weight, accent-colored live
   numeric readout via <output>) plus a flush checkbox and a live-
   swapping note/warn paragraph describing what will happen. On
   commit, the SPA also updates its local store via
   applyConfiguredWeight so the operator sees the new weight
   immediately without waiting for the next refresh.

 - ProbeHeartbeat is now state-aware: ▶ (play) at rest for up/
   down/unknown backends, ⏸ (pause) for paused, ⏹ (stop) for
   disabled/removed, ❤️ (heart) during an in-flight probe.
 - Drop the probe-done event listener — fast probes (<10ms)
   could fire probe-done in the same render tick as probe-start
   and the heart would never visibly paint. Each probe-start now
   runs a fixed 400ms scale-pop animation on a timer; subsequent
   probe-start events reset the timer, so fast cadences produce a
   continuous heart pulse.
 - Fixed wrapper box (16x14 px, overflow hidden) so the row
   doesn't jiggle when the glyph swaps between the narrow ▶/⏸/⏹
   text glyphs and the wider ❤️ emoji.

 - Brand wordmark changed from "maglev" to "vpp-maglev" and wrapped
   in an <a> linking to https://git.ipng.ch/ipng/vpp-maglev. Logo
   link changed to https://ipng.ch/. Both open in a new tab with
   rel="noopener".
 - .gitignore fix: `frontend`, `maglevc`, `maglevd` were matching
   ANY file or directory with those names anywhere in the tree,
   silently ignoring cmd/frontend and friends. Anchored with
   leading slashes so only repo-root build artifacts match.
2026-04-12 23:06:42 +02:00
Pim van Pelt
25e9d79aba Frontend: live clocks, admin mode, backend actions; packaging polish
Builds on the maglev-frontend component introduced in 284b4cc with
quality-of-life improvements, an authenticated /admin surface, a
live-action control plane, and Debian packaging cleanup.

 - Backend state now renders live: maglevd's FrontendEvent synthetic
   from==to replay hydrates FrontendSnapshot.State on WatchEvents
   subscribe, and live transitions update both the in-process cache
   and every connected browser via a new applyFrontendTransition
   reducer. Shown as a StatusBadge next to the frontend name.
 - VPP connection state surfaces in the VPP zippy title as a
   green/red badge. Driven by vpp-connect / vpp-disconnect and by
   the steady stream of vpp-api-send/recv debug heartbeats so a
   silent VPP drop is caught within one debug-log tick.
 - Probe heartbeat dot becomes ❤️ while a probe is in flight and
   reverts to · on probe-done. Fixed-size wrapper so the emoji swap
   doesn't jiggle the row; both states share the same font-size.
 - Flash component replaced its subtle background-only fade with a
   scale-pop + yellow halo box-shadow + longer duration so
   weight/effective/state changes are unmissable on tiny numeric
   cells. Initial mount still skipped via defer so no flash on load.
 - Last-transition age is now a live countdown driven by a global
   1-second ticker signal (one timer, many subscribers). Two most
   significant units: 10m30s / 1h12m / 1d16h. Sub-second ages
   render as "now" to absorb clock skew between maglevd and the
   browser.
 - Event stream is now chronological (oldest at top) with tail-
   style auto-scroll, pause/resume, and the toolbar moved below the
   list. Row separators removed. Also shown only in /admin (see
   below) so /view stays a focused read-only surface.
 - Table nowrap so backend names like nginx0-frggh0 and the
   "last transition" header don't wrap. Frontends render in the
   order returned by ListFrontends instead of Go map iteration
   order so reload doesn't shuffle VIP order.
 - IPng logo in the header, clickable, links to the git repo.
   Header padding reduced so the logo can fill the bar up to the
   separator. Version + commit + build date shown in the brand area
   (fetched once from /view/api/version).
 - "view" / "admin" mode tag moved to sit just left of the admin
   toggle button so it reads as a pair.
 - Prettier wired in as the web-side fixstyle via a new
   fixstyle-web Make target that also runs from `make fixstyle`.
   Added .prettierrc.json and .prettierignore; 8 existing files
   were normalized in place.

 - Fixed a "20555d ago" rendering bug: maglevd's synthetic
   backend-replay events (from==to, at_unix_ns=0) were corrupting
   the local cache's LastTransition via applyBackendTransition.
   Backend synthetic events are now skipped entirely (refreshAll
   covers initial hydration for backends), while frontend synthetic
   events are still applied because FrontendInfo doesn't carry
   state — the event is the only source.

 - New MAGLEV_FRONTEND_USER / MAGLEV_FRONTEND_PASSWORD env vars.
   When both are set and non-empty, /admin/ becomes a basic-auth-
   protected SPA shell backed by the same embedded index.html as
   /view/. The SPA detects its base path via a new stores/mode.ts
   isAdmin constant and conditionally renders admin-only sections
   (currently: the Event Stream / DebugPanel). When disabled,
   /admin/ returns 404 (not 501) so operators who didn't configure
   it see no teasing affordance, and the SPA's admin-toggle button
   is hidden entirely via the admin_enabled flag on
   /view/api/version.
 - basicAuth uses crypto/subtle.ConstantTimeCompare for both user
   and password so timing can't distinguish a wrong username from
   a wrong password.

 - New POST /admin/api/{maglevd}/backend/{name}/{pause|resume|
   enable|disable} endpoint, gated by the same basic-auth
   middleware as the SPA shell. maglevClient.BackendAction wraps
   the four matching gRPC RPCs and returns a fresh BackendSnapshot;
   the same transition lands via WatchEvents so every connected
   browser converges through the normal reducer path.
 - BackendActionsMenu Solid component: kebab (⋮) button in a new
   trailing column rendered only in /admin. Click-outside and
   Escape close the popover (document listeners installed only
   while open). Actions are state-aware: up/down/unknown → pause,
   disable; paused → resume, disable; disabled → enable;
   removed → menu suppressed entirely. Busy indicator per action;
   errors render inline under the item list.
 - Structured audit log: every mutation logs an
   admin-backend-action record with maglevd / backend / action /
   resulting state.

 - Renamed debian/vpp-maglevd.service → debian/vpp-maglev.service
   to align naming with the new vpp-maglev-frontend.service
   sibling. postinst handles upgrades by stopping + disabling any
   lingering vpp-maglevd.service before enabling the renamed unit;
   prerm stops both (the frontend unit is installed but not
   enabled by default — operators opt in with systemctl enable).
 - New debian/vpp-maglev-frontend.service (hardened:
   NoNewPrivileges, ProtectSystem=strict, ProtectHome, PrivateTmp,
   no capabilities). Reads the same /etc/default/vpp-maglev
   conffile and expands MAGLEV_FRONTEND_ARGS via
   `ExecStart=/usr/bin/maglev-frontend $MAGLEV_FRONTEND_ARGS` so
   word-splitting works.
 - docs/maglev-frontend.8 manpage documenting flags, endpoints,
   and SSE reverse-proxy requirements.
 - build-deb.sh: drops the commit hash from the .deb filename
   (now vpp-maglev_<version>_<arch>.deb) and no longer takes the
   commit as a CLI arg. Binaries continue to carry the commit via
   -ldflags so `maglevd --version` et al are the authoritative
   "which build is running" answer.
2026-04-12 20:04:53 +02:00
Pim van Pelt
284b4cc9a4 New maglev-frontend component; promote LB sync events to INFO
Introduces maglev-frontend, a responsive, real-time web dashboard for one
or more running maglevd instances. Source lives at cmd/frontend/; the
built binary is maglev-frontend. It is a single Go process with the
SolidJS SPA embedded via //go:embed — no runtime file dependencies.

Architecture
 - One persistent gRPC connection per configured maglevd (-server A,B,C).
   Each connection runs three background loops: a WatchEvents stream
   subscribed at log_level=debug for live events, a 30s refresh loop as
   a safety net for drift, and a 5s health loop that surfaces connection
   drops quickly.
 - In-process pub/sub broker with a 30s / 2000-event replay ring using
   <epoch>-<seq> monotonic IDs. Short browser reconnects (nginx idle,
   wifi flap, laptop wake) silently replay buffered events via the
   EventSource Last-Event-ID header; longer outages or frontend restarts
   fall through to a "resync" event that triggers a full state refetch.
 - HTTP surface: /view/ (SPA), /view/api/state, /view/api/state/{name},
   /view/api/maglevds, /view/api/version, /view/api/events (SSE),
   /healthz, and an /admin/* placeholder returning 501 for a future
   basic-auth mutation surface.
 - SSE handler follows the full operational checklist: retry hint, 15s
   : ping heartbeat, Flush after every write, r.Context().Done() teardown,
   X-Accel-Buffering: no, and no gzip.

SolidJS SPA (cmd/frontend/web/, Vite + TypeScript)
 - solid-js/store for a reactive per-maglevd state tree; reducers apply
   backend transitions, maglevd-status flips, and resync refetches.
 - Scope selector tabs for multi-maglevd support, per-maglevd frontend
   cards with pool tables showing state, configured weight, effective
   weight, and last-transition age.
 - ProbeHeartbeat component turns a middle-dot into ❤️ on probe-start and
   back on probe-done, driven by real log events; fixed-size wrapper so
   the emoji swap doesn't jiggle the row.
 - Flash wrapper animates any primitive on change (1s yellow fade via
   Web Animations API, skipped on first mount). Wired into the state
   badge, configured weight, and effective weight columns.
 - DebugPanel: chronological rolling event tail with tail-style auto-
   scroll, pause/resume, and scope/firehose filter. Syntactic highlight
   for vpp-lb-sync-* events with fixed-order attribute formatting.
 - Live effective_weight updates: vpp-lb-sync-as-added/removed/weight-
   updated log events are routed through a reducer that walks the
   snapshot's pool rows and sets effective_weight on every match
   without waiting for the 30s refresh.
 - Header shows build version + commit with build date in a tooltip,
   fetched once from /view/api/version on mount.
 - Prettier wired in as the web-side fixstyle; make fixstyle now tidies
   both Go and web in one shot via a new fixstyle-web target.

Per-mutation VPP LB sync logging
 - Promotes the addVIP/delVIP/addAS/delAS/setASWeight helpers from
   slog.Debug to slog.Info and renames them from vpp-lbsync-* to
   vpp-lb-sync-{vip-added,vip-removed,as-added,as-removed,as-weight-
   updated}. Matching rename for vpp-lb-sync-start / -done / -error /
   -vip-recreate. The Prometheus metric name (maglev_vpp_lbsync_total)
   is left alone to preserve dashboards.
 - setASWeight now takes the prior weight so the event can emit
   from=X to=Y and the UI can show the delta.
 - The vip field in every event is the bare address (no /32 or /128
   mask), matching the CLI output style.
 - Any listener on the gRPC WatchEvents stream — CLI watch events or
   maglev-frontend — now sees every VIP/AS dataplane change in real
   time without needing to raise the log level.

Build and tooling
 - Makefile: maglev-frontend added to BINARIES; build / build-amd64 /
   build-arm64 emit the binary alongside maglevd and maglevc. A new
   maglev-frontend-web target rebuilds the SolidJS bundle via npm.
 - web/dist/ is tracked so a bare `go build` keeps working for Go-only
   contributors and CI.
 - .gitignore skips cmd/frontend/web/node_modules/.

Stability fixes
 - maglevd's WatchEvents synthetic replay events (from==to, at_unix_ns=0)
   were corrupting the frontend's LastTransition cache with at=0,
   rendering as "20555d ago" in the browser. Client now skips synthetic
   events: the cache comes from refreshAll and doesn't need them.
 - Frontends, Backends, and HealthChecks are now served in the order
   returned by the corresponding List* RPC instead of Go map iteration
   order, so reloads and refreshes keep the SPA stable.
2026-04-12 17:48:31 +02:00