Initial Beach: homelab control panel

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,4 @@
+bin/
+*.db
+*.db-wal
+*.db-shm

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2026 Alex
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -0,0 +1,61 @@
+# Beach
+
+A one-page control panel for a homelab. One binary, one SQLite file, and everything is done in the web UI.
+
+| Section | Source |
+|---|---|
+| **Containers** | Docker Engine API: state, ports, health, start / stop / restart, last 200 log lines |
+| **Pools, disks, SMART** | TrueNAS REST API (`/api/v2.0`: pools, scrub state, disks, temperatures, alerts), and/or local `smartctl` |
+| **Host** | CPU, memory, swap, load, uptime and mounted filesystems from `/proc` (Linux) |
+| **Tunnels & sites** | [Hammerhead](../hammerhead)'s `GET /api/orgs/{org}/state`: site agents online/offline, port mappings up/down, target health |
+
+A section appears only when it is configured, and one failing source never takes down the page: it shows its own error.
+
+It is built in the same style as Hammerhead, Blacktip, Bamboo and Sandbar, but has no dependency on Reef.
+
+## Quick start
+
+```
+go build -o bin/ ./cmd/beach
+bin/beach -listen :8095 -data beach.db
+```
+
+Open `http://localhost:8095`, create the administrator account, then open **Settings**:
+
+- **Docker**: the socket path (default `/var/run/docker.sock`) or `tcp://host:2375`. Beach must be able to read the socket.
+- **TrueNAS**: the URL and an API key (Credentials → API Keys). Tick "self-signed certificate" if needed.
+- **smartctl**: reads SMART from the machine Beach runs on (needs `smartmontools` and permission to open the devices). Results are merged with TrueNAS by serial number.
+- **Hammerhead**: the URL, your organization ID and an API key for that organization. Read access is enough.
+
+There are two flags only: `-listen` and `-data`. There is no config file or environment variable.
+
+## Running in Docker
+
+Mount the Docker socket (this gives the container control of Docker, which is what the start/stop buttons need) and, for host metrics, run it with the host's `/proc` visible:
+
+```
+docker run -d --name beach -p 127.0.0.1:8095:8095 -v beach:/data \
+  -v /var/run/docker.sock:/var/run/docker.sock \
+  beach -data /data/beach.db
+```
+
+(There is no published image yet: build one from `go build` output in a `scratch`/`distroless` image.)
+
+## Security notes
+
+- Sign-in is a name and password (bcrypt), with a 30-day session cookie (`HttpOnly`, `SameSite=Strict`, `Secure` behind HTTPS) and a lockout after 8 failed attempts per address in 5 minutes. Every write needs an `X-Beach` header.
+- Anyone who can sign in can start, stop and restart every container and read its logs. Put Beach behind Hammerhead/Blacktip or bind it to `127.0.0.1`; do not expose it plainly.
+- API keys for TrueNAS and Hammerhead are stored in the SQLite file as plain text (they are never sent back to the browser). Protect the file like the keys themselves.
+- Beach only reads from TrueNAS and Hammerhead.
+
+## Development
+
+```
+go test ./...
+```
+
+The collectors parse recorded API shapes and `/proc` text, so the tests run anywhere. Host collection itself is Linux only (`host_linux.go`); other platforms report just the CPU count.
+
+## License
+
+MIT, see [LICENSE](LICENSE).

cmd/beach/main.go

@@ -0,0 +1,26 @@
+// Beach is a one-page control panel for a homelab: containers, disks, host load and tunnels.
+package main
+
+import (
+	"flag"
+	"log"
+	"net/http"
+	"time"
+
+	"beach/internal/beach"
+)
+
+func main() {
+	listen := flag.String("listen", ":8095", "address to listen on")
+	data := flag.String("data", "beach.db", "path of the SQLite file")
+	flag.Parse()
+
+	st, err := beach.OpenStore(*data)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer st.Close()
+	srv := &http.Server{Addr: *listen, Handler: beach.NewServer(st), ReadHeaderTimeout: 10 * time.Second}
+	log.Printf("Beach listening on %s (data: %s)", *listen, *data)
+	log.Fatal(srv.ListenAndServe())
+}

go.mod

@@ -0,0 +1,20 @@
+module beach
+
+go 1.27.3
+
+require (
+	golang.org/x/crypto v0.58.0
+	modernc.org/sqlite v1.61.0
+)
+
+require (
+	github.com/dustin/go-humanize v1.1.0 // indirect
+	github.com/google/uuid v1.6.0 // indirect
+	github.com/mattn/go-isatty v0.0.24 // indirect
+	github.com/ncruces/go-strftime v1.1.0 // indirect
+	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
+	golang.org/x/sys v0.49.0 // indirect
+	modernc.org/libc v1.79.0 // indirect
+	modernc.org/mathutil v1.7.1 // indirect
+	modernc.org/memory v1.12.1 // indirect
+)

go.sum

@@ -0,0 +1,52 @@
+github.com/dustin/go-humanize v1.1.0 h1:dbKTrvD0klcbBV/h4AWJdMuZogJACoMlvWIWZ5b2xWg=
+github.com/dustin/go-humanize v1.1.0/go.mod h1:hc1CvRkJMsgxqjmjMQF3QNRAZBwY8AXBAzKYoSX9sFI=
+github.com/google/pprof v0.0.0-20261016150608-1facf8f91b50 h1:PlNWJRxu5APSV0pWqfIsZ0qt9OOGHSWfZQ4zvx+WgWs=
+github.com/google/pprof v0.0.0-20261016150608-1facf8f91b50/go.mod h1:yUo1AMMpsPIDFGuwDK8nLcf8+vvAd5l2O6JDZ6hpwrM=
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/hashicorp/golang-lru/v2 v2.0.7 h1:a+bsQ5rvGLjzHuww6tVxozPZFVghXaHOwFs4luLUK2k=
+github.com/hashicorp/golang-lru/v2 v2.0.7/go.mod h1:QeFd9opnmA6QUJc5vARoKUSoFhyfM2/ZepoAG6RGpeM=
+github.com/mattn/go-isatty v0.0.24 h1:tGZZoVgT/KiqK1c8ocVLeDS8BSWMRd47J3Lbz7vsReI=
+github.com/mattn/go-isatty v0.0.24/go.mod h1:nMCL3Zebbrt45jsMDgnfIwz6ydEQApk5oEI3HqDio6A=
+github.com/ncruces/go-strftime v1.1.0 h1:vtPmPWMkb539RGV9WpWT9EwJGvrOCKvMNI4obWL47Hk=
+github.com/ncruces/go-strftime v1.1.0/go.mod h1:yVaq7iwCN09vHRrKBrrflXT0M9tTMG2KmZ9Fj7xeG/g=
+github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec h1:W09IVJc94icq4NjY3clb7Lk8O1qJ8BdBEF8z0ibU0rE=
+github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec/go.mod h1:qqbHyh8v60DhA7CoWK5oRCqLrMHRGoxYCSS9EjAz6Eo=
+golang.org/x/crypto v0.58.0 h1:COkYLr4k7nDI4r6QtMML2AfzeIswWHAJthLS6K/M/54=
+golang.org/x/crypto v0.58.0/go.mod h1:Xh+kl5A+M0gMiWDytH2Hhr5Z7WbNCpv/eB/EFgfSk+w=
+golang.org/x/mod v0.42.0 h1:ICeL3t2L30ljSPHHxDnR4fqVcBt/zR2zJAb9juavmQg=
+golang.org/x/mod v0.42.0/go.mod h1:u5fzIrRInkL8MaO1cbRkUHT64v303YIT5KEqpNr7jRs=
+golang.org/x/sync v0.24.0 h1:iqiDrGoDgyuvAKrhLQthUEzU/R378N78gXbBjxed7oA=
+golang.org/x/sync v0.24.0/go.mod h1:sUUOizhqBxiL6pEWpqNLUiaJn1ShEbZ6BBqskPbjZm0=
+golang.org/x/sys v0.49.0 h1:XbzkgYJHdqh/8m2Uu0W/dQv8nktxx4BFHp1M0gROTXA=
+golang.org/x/sys v0.49.0/go.mod h1:hNLxWAXmnKAxqDtdwIYC4bM9oQPEecfsnNMuSxOs3og=
+golang.org/x/tools v0.52.0 h1:ryxg4U63oaUYk7uOLTF37n43f4qgtGvqV4Ioit1BaEs=
+golang.org/x/tools v0.52.0/go.mod h1:ItcP5UNaVGG+Yc4eIYmaFLNJ4soEopkx5Y2d4lcEurs=
+modernc.org/cc/v4 v4.30.3 h1:aDq8gIX1X7+VFgO/JYYji6pLWL2H4tv3g8WatT3KCys=
+modernc.org/cc/v4 v4.30.3/go.mod h1:OnovgIhbbMXMu1aISnJ0wvVD1KnW+cAUJkIrAWh+kVI=
+modernc.org/ccgo/v4 v4.37.0 h1:BAuJCUtIHIxFIYaFhqXIw5YaoMBlNCUlFovejHfMip4=
+modernc.org/ccgo/v4 v4.37.0/go.mod h1:/8627VhwWtAbqUXmPORxFQU5SgLrAx2jl9seLw9GBhY=
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+modernc.org/fileutil v1.4.0/go.mod h1:EqdKFDxiByqxLk8ozOxObDSfcVOv/54xDs/DUHdvCUU=
+modernc.org/gc/v2 v2.6.5 h1:nyqdV8q46KvTpZlsw66kWqwXRHdjIlJOhG6kxiV/9xI=
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+modernc.org/gc/v3 v3.2.0 h1:/Y3LGDMQaoYf55PebP1qsZ5FDGgAZyG1RYKEHeQzh1o=
+modernc.org/gc/v3 v3.2.0/go.mod h1:HFK/6AGESC7Ex+EZJhJ2Gni6cTaYpSMmU/cT9RmlfYY=
+modernc.org/goabi0 v0.2.0 h1:HvEowk7LxcPd0eq6mVOAEMai46V+i7Jrj13t4AzuNks=
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+modernc.org/libc v1.79.0 h1:9Dvvv++bAMSkSuBzuOFAatbTV5OIoq6Y6FohmD3e7q8=
+modernc.org/libc v1.79.0/go.mod h1:uT3kR61NsbeKJSLqq83GJwSnZMVLlSjyAz4DfTaBy1M=
+modernc.org/mathutil v1.7.1 h1:GCZVGXdaN8gTqB1Mf/usp1Y/hSqgI2vAGGP4jZMCxOU=
+modernc.org/mathutil v1.7.1/go.mod h1:4p5IwJITfppl0G4sUEDtCr4DthTaT47/N3aT6MhfgJg=
+modernc.org/memory v1.12.1 h1:nFMiWrpStgZczNl6XI9GnIk/rWhYIyHGUaR04pGbp9g=
+modernc.org/memory v1.12.1/go.mod h1:/JP4VbVC+K5sU2wZi9bHoq2MAkCnrt2r98UGeSK7Mjw=
+modernc.org/opt v0.2.0 h1:tGyef5ApycA7FSEOMraay9SaTk5zmbx7Tu+cJs4QKZg=
+modernc.org/opt v0.2.0/go.mod h1:03fq9lsNfvkYSfxrfUhZCWPk1lm4cq4N+Bh//bEtgns=
+modernc.org/sortutil v1.2.1 h1:+xyoGf15mM3NMlPDnFqrteY07klSFxLElE2PVuWIJ7w=
+modernc.org/sortutil v1.2.1/go.mod h1:7ZI3a3REbai7gzCLcotuw9AC4VZVpYMjDzETGsSMqJE=
+modernc.org/sqlite v1.61.0 h1:sQi63oLQ9uquAUA4CzOisH35Q3pEszkPBuHM0tFL8CY=
+modernc.org/sqlite v1.61.0/go.mod h1:f4gr5tbpx2umklaT/QVtbi/50hNdM+4ng+2zMo8KXJ0=
+modernc.org/strutil v1.2.1 h1:UneZBkQA+DX2Rp35KcM69cSsNES9ly8mQWD71HKlOA0=
+modernc.org/strutil v1.2.1/go.mod h1:EHkiggD70koQxjVdSBM3JKM7k6L0FbGE5eymy9i3B9A=
+modernc.org/token v1.1.0 h1:Xl7Ap9dKaEs5kLoOQeQmPWevfnk/DM5qcLcYlA8ys6Y=
+modernc.org/token v1.1.0/go.mod h1:UGzOrNV1mAFSEB63lOFHIpNRUVMvYTc6yu1SMY/XTDM=

internal/beach/collectors_test.go

@@ -0,0 +1,253 @@
+package beach
+
+import (
+	"context"
+	"encoding/binary"
+	"net/http"
+	"net/http/httptest"
+	"strings"
+	"testing"
+)
+
+func TestParseContainers(t *testing.T) {
+	body := `[
+	 {"Id":"b","Names":["/zeta"],"Image":"nginx","State":"exited","Status":"Exited (0) 2 days ago","Created":1},
+	 {"Id":"a","Names":["/alpha"],"Image":"redis","State":"running","Status":"Up 3 hours (healthy)","Created":2,
+	  "Ports":[{"PrivatePort":6379,"PublicPort":6380,"Type":"tcp"},{"PrivatePort":6379,"PublicPort":6380,"Type":"tcp"},{"PrivatePort":9,"Type":"tcp"}]}]`
+	cs, err := parseContainers([]byte(body))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(cs) != 2 || cs[0].Name != "alpha" {
+		t.Fatalf("running containers should sort first: %+v", cs)
+	}
+	if len(cs[0].Ports) != 1 || cs[0].Ports[0] != "6380:6379/tcp" {
+		t.Fatalf("ports not deduplicated or unpublished port kept: %v", cs[0].Ports)
+	}
+	if cs[1].Ports == nil {
+		t.Fatal("ports must be an empty array, not null")
+	}
+}
+
+func frame(stream byte, s string) []byte {
+	h := make([]byte, 8)
+	h[0] = stream
+	binary.BigEndian.PutUint32(h[4:], uint32(len(s)))
+	return append(h, s...)
+}
+
+func TestDemux(t *testing.T) {
+	in := append(frame(1, "hello\n"), frame(2, "oops\n")...)
+	if got := demux(in); got != "hello\noops\n" {
+		t.Fatalf("got %q", got)
+	}
+	if got := demux([]byte("2026-01-01T00:00:00Z plain tty line\n")); !strings.Contains(got, "plain tty line") {
+		t.Fatalf("unframed text lost: %q", got)
+	}
+}
+
+func TestDockerAPI(t *testing.T) {
+	var calls []string
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		calls = append(calls, r.Method+" "+r.URL.Path)
+		switch {
+		case r.URL.Path == "/containers/json":
+			w.Write([]byte(`[{"Id":"abc","Names":["/web"],"State":"running","Status":"Up"}]`))
+		case strings.HasSuffix(r.URL.Path, "/json"):
+			w.Write([]byte(`{"Config":{"Tty":false}}`))
+		case strings.HasSuffix(r.URL.Path, "/logs"):
+			w.Write(frame(1, "line one\n"))
+		case strings.HasSuffix(r.URL.Path, "/stop"):
+			w.WriteHeader(304)
+		case strings.HasSuffix(r.URL.Path, "/start"):
+			w.WriteHeader(404)
+			w.Write([]byte(`{"message":"No such container: abc"}`))
+		}
+	}))
+	defer srv.Close()
+	d := NewDocker("tcp://" + strings.TrimPrefix(srv.URL, "http://"))
+	ctx := context.Background()
+	cs, err := d.List(ctx)
+	if err != nil || len(cs) != 1 || cs[0].Name != "web" {
+		t.Fatalf("list: %v %+v", err, cs)
+	}
+	if out, err := d.Logs(ctx, "abc", 50); err != nil || out != "line one\n" {
+		t.Fatalf("logs: %q %v", out, err)
+	}
+	if err := d.Action(ctx, "abc", "stop"); err != nil {
+		t.Fatalf("304 means already stopped, not an error: %v", err)
+	}
+	if err := d.Action(ctx, "abc", "start"); err == nil || !strings.Contains(err.Error(), "No such container") {
+		t.Fatalf("engine message should surface: %v", err)
+	}
+	if err := d.Action(ctx, "abc", "rm"); err == nil {
+		t.Fatal("unknown action must be refused")
+	}
+}
+
+func TestTrueNAS(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.Header.Get("Authorization") != "Bearer secret" {
+			w.WriteHeader(401)
+			return
+		}
+		switch r.URL.Path {
+		case "/api/v2.0/pool":
+			w.Write([]byte(`[{"name":"tank","status":"ONLINE","healthy":true,"size":1000,"allocated":250,
+			  "scan":{"function":"SCRUB","state":"FINISHED","errors":0}},
+			  {"name":"fast","status":"DEGRADED","healthy":false,"size":0,"allocated":0,"scan":{"function":"SCRUB","state":"SCANNING","percentage":41.2}}]`))
+		case "/api/v2.0/disk":
+			w.Write([]byte(`[{"name":"sdb","model":"WD","serial":"S2","size":4000,"pool":"tank"},{"name":"sda","model":"WD","serial":"S1","size":4000,"pool":null}]`))
+		case "/api/v2.0/disk/temperatures":
+			w.Write([]byte(`{"sda":34,"sdb":null}`))
+		case "/api/v2.0/alert/list":
+			w.Write([]byte(`[{"level":"WARNING","formatted":"Pool degraded","dismissed":false},{"level":"INFO","formatted":"old","dismissed":true}]`))
+		default:
+			w.WriteHeader(404)
+		}
+	}))
+	defer srv.Close()
+
+	st := NewTrueNAS(srv.URL, "secret", false).Collect(context.Background())
+	if st.Error != "" {
+		t.Fatal(st.Error)
+	}
+	if len(st.Pools) != 2 || st.Pools[0].Name != "fast" {
+		t.Fatalf("pools: %+v", st.Pools)
+	}
+	tank := st.Pools[1]
+	if tank.UsedPct != 25 || tank.Scan != "scrub finished, 0 errors" || !tank.Healthy {
+		t.Fatalf("tank: %+v", tank)
+	}
+	if st.Pools[0].Scan != "scrub in progress 41%" {
+		t.Fatalf("scan progress: %q", st.Pools[0].Scan)
+	}
+	if len(st.Disks) != 2 || st.Disks[0].Name != "sda" || st.Disks[0].TempC != 34 || st.Disks[1].TempC != 0 {
+		t.Fatalf("disks: %+v", st.Disks)
+	}
+	if len(st.Alerts) != 1 || st.Alerts[0].Message != "Pool degraded" {
+		t.Fatalf("dismissed alerts must be hidden: %+v", st.Alerts)
+	}
+
+	bad := NewTrueNAS(srv.URL, "wrong", false).Collect(context.Background())
+	if !strings.Contains(bad.Error, "API key rejected") {
+		t.Fatalf("bad key error: %q", bad.Error)
+	}
+}
+
+const smartJSON = `{"device":{"name":"/dev/sda"},"model_name":"ST4000","serial_number":"Z1","user_capacity":{"bytes":4000787030016},
+ "smart_status":{"passed":%s},"temperature":{"current":38}}`
+
+func TestParseSmartctl(t *testing.T) {
+	d, err := parseSmartctl([]byte(strings.Replace(smartJSON, "%s", "true", 1)))
+	if err != nil || d.Health != "PASSED" || d.TempC != 38 || d.Model != "ST4000" {
+		t.Fatalf("%+v %v", d, err)
+	}
+	d, _ = parseSmartctl([]byte(strings.Replace(smartJSON, "%s", "false", 1)))
+	if d.Health != "FAILED" {
+		t.Fatalf("failed disk reported as %q", d.Health)
+	}
+	d, _ = parseSmartctl([]byte(`{"device":{"name":"/dev/sdc"}}`))
+	if d.Health != "" {
+		t.Fatalf("no verdict must stay unknown, got %q", d.Health)
+	}
+}
+
+func TestLocalSmartAndMerge(t *testing.T) {
+	fake := func(ctx context.Context, args ...string) ([]byte, error) {
+		if args[0] == "--scan" {
+			return []byte(`{"devices":[{"name":"/dev/sda"},{"name":"/dev/sdz"}]}`), nil
+		}
+		if args[len(args)-1] == "/dev/sda" {
+			return []byte(strings.Replace(smartJSON, "%s", "true", 1)), nil
+		}
+		return []byte(`{"device":{"name":"/dev/sdz"},"serial_number":"ONLY","smart_status":{"passed":false}}`), nil
+	}
+	local, err := LocalSmart(context.Background(), fake)
+	if err != nil || len(local) != 2 {
+		t.Fatalf("%v %+v", err, local)
+	}
+	tn := []Disk{{Name: "sda", Serial: "Z1", Source: "truenas"}}
+	merged := mergeDisks(tn, local)
+	if len(merged) != 2 || merged[0].Health != "PASSED" || merged[0].TempC != 38 || merged[0].Source != "truenas" {
+		t.Fatalf("same disk should be merged, not duplicated: %+v", merged)
+	}
+	if merged[1].Serial != "ONLY" || merged[1].Health != "FAILED" {
+		t.Fatalf("smartctl-only disk missing: %+v", merged)
+	}
+}
+
+func TestHostParsers(t *testing.T) {
+	a, err := parseCPU("cpu  100 0 100 700 100 0 0 0 0 0\ncpu0 1 1 1 1 1 1 1 1 1 1\n")
+	if err != nil {
+		t.Fatal(err)
+	}
+	b, _ := parseCPU("cpu  200 0 200 750 150 0 0 0 0 0\n")
+	// between samples: busy +200, idle(+iowait) +100
+	if got := cpuPct(a, b); got < 66 || got > 67 {
+		t.Fatalf("cpu %.1f", got)
+	}
+	if cpuPct(b, a) != 0 {
+		t.Fatal("a counter reset must not give a negative or huge value")
+	}
+	total, used, st, su := parseMeminfo("MemTotal: 1000 kB\nMemAvailable: 400 kB\nSwapTotal: 200 kB\nSwapFree: 150 kB\n")
+	if total != 1000*1024 || used != 600*1024 || st != 200*1024 || su != 50*1024 {
+		t.Fatalf("%d %d %d %d", total, used, st, su)
+	}
+	if l := parseLoad("0.50 1.25 2.00 1/200 999"); l != [3]float64{0.5, 1.25, 2} {
+		t.Fatalf("%v", l)
+	}
+	if parseUptime("3600.55 7000.1") != 3600.55 {
+		t.Fatal("uptime")
+	}
+	mounts := "/dev/sda1 / ext4 rw 0 0\ntmpfs /run tmpfs rw 0 0\ntank/data /mnt/tank zfs rw 0 0\n/dev/sda1 /var/lib/docker/x ext4 rw 0 0\n/dev/sdb1 /var/lib/docker/y ext4 rw 0 0\n"
+	if got := realMounts(mounts); len(got) != 2 || got[0] != "/" || got[1] != "/mnt/tank" {
+		t.Fatalf("%v", got)
+	}
+	if h := CollectHost(); h.CPUs < 1 {
+		t.Fatal("CollectHost should report CPU count")
+	}
+}
+
+func TestParseTunnels(t *testing.T) {
+	body := `{"sites":[{"id":"s1","name":"homelab","version":"v0.1.8"},{"id":"s2","name":"vps","local":true}],
+	 "online":{"s1":true,"s2":false},
+	 "mappings":[{"name":"wiki","proto":"web","hostname":"wiki.example.com","port":443,"enabled":true,"statusKnown":true,
+	   "targets":[{},{}],"status":{"targets":[{"healthy":true},{"healthy":false}]}},
+	  {"name":"ssh","proto":"tcp","port":22,"enabled":true,"statusKnown":true,"status":{"error":"bind: in use"}},
+	  {"name":"off","proto":"tcp","port":1,"enabled":false}]}`
+	tn, err := parseTunnels([]byte(body))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(tn.Sites) != 2 || tn.Sites[0].Name != "homelab" || !tn.Sites[0].Online || tn.Sites[1].Online {
+		t.Fatalf("sites: %+v", tn.Sites)
+	}
+	byName := map[string]TunnelPort{}
+	for _, p := range tn.Ports {
+		byName[p.Name] = p
+	}
+	if w := byName["wiki"]; !w.Up || w.Healthy != 1 || w.Targets != 2 {
+		t.Fatalf("wiki: %+v", w)
+	}
+	if byName["ssh"].Up || byName["off"].Up {
+		t.Fatal("errored or disabled ports must not be up")
+	}
+}
+
+func TestFetchTunnels(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path != "/api/orgs/o1/state" || r.Header.Get("Authorization") != "Bearer k" {
+			w.WriteHeader(401)
+			return
+		}
+		w.Write([]byte(`{"sites":[],"mappings":[],"online":{}}`))
+	}))
+	defer srv.Close()
+	if tn := FetchTunnels(context.Background(), srv.URL+"/", "k", "o1"); tn.Error != "" {
+		t.Fatal(tn.Error)
+	}
+	if tn := FetchTunnels(context.Background(), srv.URL, "nope", "o1"); !strings.Contains(tn.Error, "401") {
+		t.Fatalf("expected 401 error, got %q", tn.Error)
+	}
+}

internal/beach/docker.go

@@ -0,0 +1,179 @@
+package beach
+
+import (
+	"bytes"
+	"context"
+	"encoding/binary"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"net/url"
+	"sort"
+	"strings"
+	"time"
+)
+
+const defaultDockerHost = "/var/run/docker.sock"
+
+// Container is one row in the containers table.
+type Container struct {
+	ID      string   `json:"id"`
+	Name    string   `json:"name"`
+	Image   string   `json:"image"`
+	State   string   `json:"state"`  // running, exited, ...
+	Status  string   `json:"status"` // "Up 3 hours (healthy)"
+	Ports   []string `json:"ports"`
+	Created int64    `json:"created"`
+}
+
+// Docker talks to the Engine API over a unix socket or plain TCP.
+type Docker struct {
+	base   string
+	client *http.Client
+}
+
+// NewDocker accepts "/var/run/docker.sock", "unix:///path", "tcp://host:2375" or "host:2375".
+func NewDocker(host string) *Docker {
+	host = strings.TrimSpace(host)
+	d := &Docker{base: "http://docker"}
+	tr := &http.Transport{}
+	switch {
+	case strings.HasPrefix(host, "tcp://"), strings.HasPrefix(host, "http://"):
+		d.base = "http://" + strings.TrimPrefix(strings.TrimPrefix(host, "tcp://"), "http://")
+	case strings.HasPrefix(host, "/"), strings.HasPrefix(host, "unix://"):
+		path := strings.TrimPrefix(host, "unix://")
+		tr.DialContext = func(ctx context.Context, _, _ string) (net.Conn, error) {
+			return (&net.Dialer{Timeout: 3 * time.Second}).DialContext(ctx, "unix", path)
+		}
+	default:
+		d.base = "http://" + host
+	}
+	d.client = &http.Client{Transport: tr, Timeout: 30 * time.Second}
+	return d
+}
+
+func (d *Docker) do(ctx context.Context, method, path string) ([]byte, error) {
+	req, err := http.NewRequestWithContext(ctx, method, d.base+path, nil)
+	if err != nil {
+		return nil, err
+	}
+	resp, err := d.client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+	body, _ := io.ReadAll(io.LimitReader(resp.Body, 16<<20))
+	if resp.StatusCode >= 300 && resp.StatusCode != http.StatusNotModified {
+		var e struct{ Message string }
+		json.Unmarshal(body, &e)
+		if e.Message == "" {
+			e.Message = resp.Status
+		}
+		return nil, fmt.Errorf("docker: %s", e.Message)
+	}
+	return body, nil
+}
+
+func (d *Docker) List(ctx context.Context) ([]Container, error) {
+	body, err := d.do(ctx, "GET", "/containers/json?all=1")
+	if err != nil {
+		return nil, err
+	}
+	return parseContainers(body)
+}
+
+func parseContainers(body []byte) ([]Container, error) {
+	var raw []struct {
+		ID      string
+		Names   []string
+		Image   string
+		State   string
+		Status  string
+		Created int64
+		Ports   []struct {
+			PrivatePort int
+			PublicPort  int
+			Type        string
+		}
+	}
+	if err := json.Unmarshal(body, &raw); err != nil {
+		return nil, err
+	}
+	out := make([]Container, 0, len(raw))
+	for _, r := range raw {
+		c := Container{ID: r.ID, Image: r.Image, State: r.State, Status: r.Status, Created: r.Created, Ports: []string{}}
+		if len(r.Names) > 0 {
+			c.Name = strings.TrimPrefix(r.Names[0], "/")
+		}
+		seen := map[string]bool{}
+		for _, p := range r.Ports {
+			if p.PublicPort == 0 {
+				continue
+			}
+			s := fmt.Sprintf("%d:%d/%s", p.PublicPort, p.PrivatePort, p.Type)
+			if !seen[s] { // IPv4 and IPv6 bindings repeat
+				seen[s] = true
+				c.Ports = append(c.Ports, s)
+			}
+		}
+		out = append(out, c)
+	}
+	sort.Slice(out, func(i, j int) bool {
+		if (out[i].State == "running") != (out[j].State == "running") {
+			return out[i].State == "running"
+		}
+		return out[i].Name < out[j].Name
+	})
+	return out, nil
+}
+
+// Action is one of start, stop, restart.
+func (d *Docker) Action(ctx context.Context, id, action string) error {
+	switch action {
+	case "start", "stop", "restart":
+	default:
+		return fmt.Errorf("unknown action %q", action)
+	}
+	_, err := d.do(ctx, "POST", "/containers/"+url.PathEscape(id)+"/"+action)
+	return err
+}
+
+func (d *Docker) Logs(ctx context.Context, id string, tail int) (string, error) {
+	if tail < 1 || tail > 5000 {
+		tail = 200
+	}
+	// the multiplexed format is only used for containers without a TTY
+	var info struct{ Config struct{ Tty bool } }
+	if b, err := d.do(ctx, "GET", "/containers/"+url.PathEscape(id)+"/json"); err == nil {
+		json.Unmarshal(b, &info)
+	}
+	body, err := d.do(ctx, "GET", fmt.Sprintf("/containers/%s/logs?stdout=1&stderr=1&timestamps=1&tail=%d", url.PathEscape(id), tail))
+	if err != nil {
+		return "", err
+	}
+	if info.Config.Tty {
+		return string(body), nil
+	}
+	return demux(body), nil
+}
+
+// demux strips the 8-byte stream headers Docker puts in front of each log frame.
+func demux(b []byte) string {
+	var out bytes.Buffer
+	for len(b) >= 8 {
+		if b[0] > 2 || b[1] != 0 || b[2] != 0 || b[3] != 0 { // not framed; treat as plain text
+			out.Write(b)
+			return out.String()
+		}
+		n := int(binary.BigEndian.Uint32(b[4:8]))
+		b = b[8:]
+		if n > len(b) {
+			n = len(b)
+		}
+		out.Write(b[:n])
+		b = b[n:]
+	}
+	return out.String()
+}

internal/beach/hammerhead.go

@@ -0,0 +1,111 @@
+package beach
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"sort"
+	"strings"
+	"time"
+)
+
+type TunnelSite struct {
+	Name     string    `json:"name"`
+	Online   bool      `json:"online"`
+	Local    bool      `json:"local"`
+	Version  string    `json:"version,omitempty"`
+	LastSeen time.Time `json:"lastSeen"`
+}
+
+type TunnelPort struct {
+	Name     string `json:"name"`
+	Proto    string `json:"proto"`
+	Hostname string `json:"hostname,omitempty"`
+	Port     int    `json:"port"`
+	Enabled  bool   `json:"enabled"`
+	Up       bool   `json:"up"` // the edge reports it listening without error
+	Known    bool   `json:"known"`
+	Healthy  int    `json:"healthy"`
+	Targets  int    `json:"targets"`
+}
+
+type Tunnels struct {
+	Sites []TunnelSite `json:"sites"`
+	Ports []TunnelPort `json:"ports"`
+	Error string       `json:"error,omitempty"`
+}
+
+// FetchTunnels reads GET /api/orgs/{org}/state from Hammerhead with an API key.
+func FetchTunnels(ctx context.Context, base, key, org string) Tunnels {
+	u := strings.TrimRight(base, "/") + "/api/orgs/" + url.PathEscape(org) + "/state"
+	req, err := http.NewRequestWithContext(ctx, "GET", u, nil)
+	if err != nil {
+		return Tunnels{Error: err.Error()}
+	}
+	req.Header.Set("Authorization", "Bearer "+key)
+	resp, err := (&http.Client{Timeout: 10 * time.Second}).Do(req)
+	if err != nil {
+		return Tunnels{Error: err.Error()}
+	}
+	defer resp.Body.Close()
+	b, _ := io.ReadAll(io.LimitReader(resp.Body, 8<<20))
+	if resp.StatusCode != 200 {
+		return Tunnels{Error: fmt.Sprintf("hammerhead: %s", resp.Status)}
+	}
+	t, err := parseTunnels(b)
+	if err != nil {
+		return Tunnels{Error: err.Error()}
+	}
+	return t
+}
+
+func parseTunnels(b []byte) (Tunnels, error) {
+	var st struct {
+		Sites []struct {
+			ID       string    `json:"id"`
+			Name     string    `json:"name"`
+			Local    bool      `json:"local"`
+			Version  string    `json:"version"`
+			LastSeen time.Time `json:"lastSeen"`
+		} `json:"sites"`
+		Online   map[string]bool `json:"online"`
+		Mappings []struct {
+			Name     string `json:"name"`
+			Proto    string `json:"proto"`
+			Hostname string `json:"hostname"`
+			Port     int    `json:"port"`
+			Enabled  bool   `json:"enabled"`
+			Targets  []any  `json:"targets"`
+			Status   struct {
+				Error   string `json:"error"`
+				Targets []struct {
+					Healthy bool `json:"healthy"`
+				} `json:"targets"`
+			} `json:"status"`
+			Known bool `json:"statusKnown"`
+		} `json:"mappings"`
+	}
+	if err := json.Unmarshal(b, &st); err != nil {
+		return Tunnels{}, fmt.Errorf("hammerhead: unexpected response: %w", err)
+	}
+	t := Tunnels{Sites: []TunnelSite{}, Ports: []TunnelPort{}}
+	for _, s := range st.Sites {
+		t.Sites = append(t.Sites, TunnelSite{Name: s.Name, Online: st.Online[s.ID], Local: s.Local, Version: s.Version, LastSeen: s.LastSeen})
+	}
+	for _, m := range st.Mappings {
+		p := TunnelPort{Name: m.Name, Proto: m.Proto, Hostname: m.Hostname, Port: m.Port, Enabled: m.Enabled, Known: m.Known, Targets: len(m.Targets)}
+		p.Up = m.Enabled && m.Known && m.Status.Error == ""
+		for _, th := range m.Status.Targets {
+			if th.Healthy {
+				p.Healthy++
+			}
+		}
+		t.Ports = append(t.Ports, p)
+	}
+	sort.Slice(t.Sites, func(i, j int) bool { return t.Sites[i].Name < t.Sites[j].Name })
+	sort.Slice(t.Ports, func(i, j int) bool { return t.Ports[i].Name < t.Ports[j].Name })
+	return t, nil
+}

internal/beach/host.go

@@ -0,0 +1,129 @@
+package beach
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// Host is the machine Beach runs on.
+type Host struct {
+	Hostname  string       `json:"hostname"`
+	Uptime    float64      `json:"uptimeSeconds"`
+	Load      [3]float64   `json:"load"`
+	CPUPct    float64      `json:"cpuPct"`
+	CPUs      int          `json:"cpus"`
+	MemTotal  uint64       `json:"memTotal"`
+	MemUsed   uint64       `json:"memUsed"`
+	SwapTotal uint64       `json:"swapTotal"`
+	SwapUsed  uint64       `json:"swapUsed"`
+	Disks     []Filesystem `json:"filesystems"`
+	Supported bool         `json:"supported"`
+}
+
+type Filesystem struct {
+	Mount string `json:"mount"`
+	Total uint64 `json:"total"`
+	Used  uint64 `json:"used"`
+}
+
+// cpuTimes is the aggregate line of /proc/stat.
+type cpuTimes struct{ busy, total uint64 }
+
+func parseCPU(stat string) (cpuTimes, error) {
+	for _, line := range strings.Split(stat, "\n") {
+		f := strings.Fields(line)
+		if len(f) < 5 || f[0] != "cpu" {
+			continue
+		}
+		var v []uint64
+		for _, s := range f[1:] {
+			n, err := strconv.ParseUint(s, 10, 64)
+			if err != nil {
+				return cpuTimes{}, err
+			}
+			v = append(v, n)
+		}
+		var total uint64
+		for i, n := range v {
+			if i < 8 { // guest times are already counted in user/nice
+				total += n
+			}
+		}
+		idle := v[3]
+		if len(v) > 4 {
+			idle += v[4] // iowait
+		}
+		return cpuTimes{busy: total - idle, total: total}, nil
+	}
+	return cpuTimes{}, fmt.Errorf("no cpu line")
+}
+
+// cpuPct is the busy share between two samples.
+func cpuPct(a, b cpuTimes) float64 {
+	if b.total <= a.total || b.busy < a.busy {
+		return 0
+	}
+	return float64(b.busy-a.busy) / float64(b.total-a.total) * 100
+}
+
+func parseMeminfo(s string) (total, used, swapTotal, swapUsed uint64) {
+	kb := map[string]uint64{}
+	for _, line := range strings.Split(s, "\n") {
+		f := strings.Fields(line)
+		if len(f) >= 2 {
+			n, _ := strconv.ParseUint(f[1], 10, 64)
+			kb[strings.TrimSuffix(f[0], ":")] = n * 1024
+		}
+	}
+	total = kb["MemTotal"]
+	avail, ok := kb["MemAvailable"]
+	if !ok {
+		avail = kb["MemFree"] + kb["Buffers"] + kb["Cached"]
+	}
+	if avail <= total {
+		used = total - avail
+	}
+	swapTotal = kb["SwapTotal"]
+	if kb["SwapFree"] <= swapTotal {
+		swapUsed = swapTotal - kb["SwapFree"]
+	}
+	return
+}
+
+func parseLoad(s string) (l [3]float64) {
+	f := strings.Fields(s)
+	for i := 0; i < 3 && i < len(f); i++ {
+		l[i], _ = strconv.ParseFloat(f[i], 64)
+	}
+	return
+}
+
+func parseUptime(s string) float64 {
+	f := strings.Fields(s)
+	if len(f) == 0 {
+		return 0
+	}
+	v, _ := strconv.ParseFloat(f[0], 64)
+	return v
+}
+
+// realMounts picks the mounts worth showing from /proc/mounts: real block or
+// ZFS filesystems, once per device, without Docker's own overlay mounts.
+func realMounts(mounts string) []string {
+	ok := map[string]bool{"ext4": true, "xfs": true, "btrfs": true, "zfs": true, "ext3": true, "f2fs": true, "vfat": true, "ntfs": true, "ntfs3": true, "exfat": true}
+	seen := map[string]bool{}
+	var out []string
+	for _, line := range strings.Split(mounts, "\n") {
+		f := strings.Fields(line)
+		if len(f) < 3 || !ok[f[2]] || seen[f[0]] {
+			continue
+		}
+		if strings.HasPrefix(f[1], "/var/lib/docker") || strings.HasPrefix(f[1], "/proc") || strings.HasPrefix(f[1], "/sys") {
+			continue
+		}
+		seen[f[0]] = true
+		out = append(out, f[1])
+	}
+	return out
+}

internal/beach/host_linux.go

@@ -0,0 +1,53 @@
+//go:build linux
+
+package beach
+
+import (
+	"os"
+	"runtime"
+	"sync"
+	"syscall"
+	"time"
+)
+
+var (
+	cpuMu   sync.Mutex
+	lastCPU cpuTimes
+	lastAt  time.Time
+	lastPct float64
+)
+
+func readFile(p string) string { b, _ := os.ReadFile(p); return string(b) }
+
+// CollectHost reads /proc. CPU use is the change since the previous call; the
+// first call takes a short sample of its own.
+func CollectHost() Host {
+	h := Host{Supported: true, CPUs: runtime.NumCPU(), Disks: []Filesystem{}}
+	h.Hostname, _ = os.Hostname()
+	h.Uptime = parseUptime(readFile("/proc/uptime"))
+	h.Load = parseLoad(readFile("/proc/loadavg"))
+	h.MemTotal, h.MemUsed, h.SwapTotal, h.SwapUsed = parseMeminfo(readFile("/proc/meminfo"))
+	cpuMu.Lock()
+	if now, err := parseCPU(readFile("/proc/stat")); err == nil {
+		if lastAt.IsZero() {
+			time.Sleep(250 * time.Millisecond)
+			if n2, err := parseCPU(readFile("/proc/stat")); err == nil {
+				lastPct, now = cpuPct(now, n2), n2
+			}
+			lastCPU, lastAt = now, time.Now()
+		} else if time.Since(lastAt) > 500*time.Millisecond {
+			lastPct = cpuPct(lastCPU, now)
+			lastCPU, lastAt = now, time.Now()
+		}
+	}
+	h.CPUPct = lastPct
+	cpuMu.Unlock()
+	for _, m := range realMounts(readFile("/proc/mounts")) {
+		var st syscall.Statfs_t
+		if syscall.Statfs(m, &st) == nil && st.Blocks > 0 {
+			bs := uint64(st.Bsize)
+			h.Disks = append(h.Disks, Filesystem{Mount: m, Total: st.Blocks * bs, Used: (st.Blocks - st.Bfree) * bs})
+		}
+	}
+	return h
+}

internal/beach/host_other.go

@@ -0,0 +1,15 @@
+//go:build !linux
+
+package beach
+
+import (
+	"os"
+	"runtime"
+)
+
+// CollectHost has no portable source off Linux; Beach is meant to run on the homelab box.
+func CollectHost() Host {
+	h := Host{CPUs: runtime.NumCPU(), Disks: []Filesystem{}}
+	h.Hostname, _ = os.Hostname()
+	return h
+}

internal/beach/server.go

@@ -0,0 +1,385 @@
+package beach
+
+import (
+	"context"
+	"embed"
+	"encoding/json"
+	"errors"
+	"io/fs"
+	"net"
+	"net/http"
+	"regexp"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+
+	"golang.org/x/crypto/bcrypt"
+)
+
+//go:embed web
+var webFS embed.FS
+
+const cookieName = "beach_session"
+
+var dummyHash = func() string {
+	h, _ := bcrypt.GenerateFromPassword([]byte("beach"), bcrypt.DefaultCost)
+	return string(h)
+}()
+
+type Server struct {
+	st  *Store
+	mux *http.ServeMux
+
+	smart runner // replaceable in tests
+
+	mu    sync.Mutex
+	fails map[string][]time.Time // login failures per client address
+}
+
+func NewServer(st *Store) *Server {
+	s := &Server{st: st, mux: http.NewServeMux(), smart: execSmartctl, fails: map[string][]time.Time{}}
+	web, _ := fs.Sub(webFS, "web")
+	s.mux.Handle("GET /", http.FileServerFS(web))
+	s.mux.HandleFunc("GET /api/session", s.session)
+	s.mux.HandleFunc("POST /api/setup", s.setup)
+	s.mux.HandleFunc("POST /api/login", s.login)
+	s.mux.HandleFunc("POST /api/logout", s.logout)
+	s.mux.HandleFunc("GET /api/overview", s.auth(s.overview))
+	s.mux.HandleFunc("GET /api/settings", s.auth(s.getSettings))
+	s.mux.HandleFunc("PUT /api/settings", s.auth(s.putSettings))
+	s.mux.HandleFunc("POST /api/containers/{id}/{action}", s.auth(s.containerAction))
+	s.mux.HandleFunc("GET /api/containers/{id}/logs", s.auth(s.containerLogs))
+	return s
+}
+
+func (s *Server) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("X-Content-Type-Options", "nosniff")
+	w.Header().Set("X-Frame-Options", "DENY")
+	w.Header().Set("Content-Security-Policy", "default-src 'self'; style-src 'self' 'unsafe-inline'; script-src 'self' 'unsafe-inline'; img-src 'self' data:")
+	// a custom header on every write keeps cross-site forms from reaching the API
+	if r.Method != "GET" && r.Method != "HEAD" && r.Header.Get("X-Beach") == "" {
+		fail(w, 403, errors.New("missing X-Beach header"))
+		return
+	}
+	s.mux.ServeHTTP(w, r)
+}
+
+func writeJSON(w http.ResponseWriter, code int, v any) {
+	w.Header().Set("Content-Type", "application/json")
+	w.Header().Set("Cache-Control", "no-store")
+	w.WriteHeader(code)
+	json.NewEncoder(w).Encode(v)
+}
+
+func fail(w http.ResponseWriter, code int, err error) {
+	writeJSON(w, code, map[string]string{"error": err.Error()})
+}
+
+func (s *Server) user(r *http.Request) string {
+	c, err := r.Cookie(cookieName)
+	if err != nil {
+		return ""
+	}
+	u, err := s.st.SessionUser(c.Value)
+	if err != nil {
+		return ""
+	}
+	return u
+}
+
+func (s *Server) auth(fn http.HandlerFunc) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		if s.user(r) == "" {
+			fail(w, 401, errors.New("sign in to continue"))
+			return
+		}
+		fn(w, r)
+	}
+}
+
+func (s *Server) session(w http.ResponseWriter, r *http.Request) {
+	u := s.user(r)
+	writeJSON(w, 200, map[string]any{"setup": !s.st.HasUsers(), "user": u})
+}
+
+type creds struct{ Name, Password string }
+
+func (s *Server) startSession(w http.ResponseWriter, r *http.Request, name string) {
+	tok, err := s.st.NewSession(name, 30*24*time.Hour)
+	if err != nil {
+		fail(w, 500, err)
+		return
+	}
+	http.SetCookie(w, &http.Cookie{Name: cookieName, Value: tok, Path: "/", HttpOnly: true, SameSite: http.SameSiteStrictMode,
+		Secure: r.TLS != nil || r.Header.Get("X-Forwarded-Proto") == "https", MaxAge: 30 * 24 * 3600})
+	writeJSON(w, 200, map[string]any{"user": name})
+}
+
+func (s *Server) setup(w http.ResponseWriter, r *http.Request) {
+	var c creds
+	if json.NewDecoder(http.MaxBytesReader(w, r.Body, 1<<16)).Decode(&c) != nil {
+		fail(w, 400, errors.New("bad request"))
+		return
+	}
+	c.Name = strings.TrimSpace(c.Name)
+	if c.Name == "" || len(c.Password) < 8 {
+		fail(w, 400, errors.New("choose a name and a password of at least 8 characters"))
+		return
+	}
+	// serialize so two simultaneous first-run requests cannot both win
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.st.HasUsers() {
+		fail(w, 409, errors.New("Beach is already set up"))
+		return
+	}
+	h, err := bcrypt.GenerateFromPassword([]byte(c.Password), bcrypt.DefaultCost)
+	if err != nil {
+		fail(w, 500, err)
+		return
+	}
+	if err := s.st.AddUser(c.Name, string(h)); err != nil {
+		fail(w, 500, err)
+		return
+	}
+	s.startSession(w, r, c.Name)
+}
+
+func clientIP(r *http.Request) string {
+	h, _, err := net.SplitHostPort(r.RemoteAddr)
+	if err != nil {
+		return r.RemoteAddr
+	}
+	return h
+}
+
+// tooManyFails allows 8 failed sign-ins per client in 5 minutes.
+func (s *Server) tooManyFails(ip string, record bool) bool {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	now := time.Now()
+	kept := s.fails[ip][:0]
+	for _, t := range s.fails[ip] {
+		if now.Sub(t) < 5*time.Minute {
+			kept = append(kept, t)
+		}
+	}
+	if record {
+		kept = append(kept, now)
+	}
+	s.fails[ip] = kept
+	return len(kept) >= 8
+}
+
+func (s *Server) login(w http.ResponseWriter, r *http.Request) {
+	ip := clientIP(r)
+	if s.tooManyFails(ip, false) {
+		fail(w, 429, errors.New("too many attempts, try again in a few minutes"))
+		return
+	}
+	var c creds
+	if json.NewDecoder(http.MaxBytesReader(w, r.Body, 1<<16)).Decode(&c) != nil {
+		fail(w, 400, errors.New("bad request"))
+		return
+	}
+	hash, ok := s.st.UserHash(strings.TrimSpace(c.Name))
+	if !ok {
+		hash = dummyHash // spend the same time as a real check so names cannot be probed
+	}
+	if bcrypt.CompareHashAndPassword([]byte(hash), []byte(c.Password)) != nil || !ok {
+		s.tooManyFails(ip, true)
+		fail(w, 401, errors.New("wrong name or password"))
+		return
+	}
+	s.startSession(w, r, strings.TrimSpace(c.Name))
+}
+
+func (s *Server) logout(w http.ResponseWriter, r *http.Request) {
+	if c, err := r.Cookie(cookieName); err == nil {
+		s.st.DeleteSession(c.Value)
+	}
+	http.SetCookie(w, &http.Cookie{Name: cookieName, Path: "/", MaxAge: -1})
+	writeJSON(w, 200, map[string]bool{"ok": true})
+}
+
+// settingsView never carries secrets back to the browser.
+type settingsView struct {
+	Settings
+	TrueNASKeySet    bool `json:"truenasKeySet"`
+	HammerheadKeySet bool `json:"hammerheadKeySet"`
+}
+
+func (s *Server) getSettings(w http.ResponseWriter, r *http.Request) {
+	set := s.st.Settings()
+	v := settingsView{Settings: set, TrueNASKeySet: set.TrueNAS.APIKey != "", HammerheadKeySet: set.Hammerhead.APIKey != ""}
+	v.TrueNAS.APIKey, v.Hammerhead.APIKey = "", ""
+	writeJSON(w, 200, v)
+}
+
+func (s *Server) putSettings(w http.ResponseWriter, r *http.Request) {
+	var in Settings
+	if json.NewDecoder(http.MaxBytesReader(w, r.Body, 1<<16)).Decode(&in) != nil {
+		fail(w, 400, errors.New("bad request"))
+		return
+	}
+	old := s.st.Settings()
+	// a blank key box means "keep the saved key"
+	if in.TrueNAS.APIKey == "" {
+		in.TrueNAS.APIKey = old.TrueNAS.APIKey
+	}
+	if in.Hammerhead.APIKey == "" {
+		in.Hammerhead.APIKey = old.Hammerhead.APIKey
+	}
+	for _, u := range []string{in.TrueNAS.URL, in.Hammerhead.URL} {
+		if u != "" && !strings.HasPrefix(u, "http://") && !strings.HasPrefix(u, "https://") {
+			fail(w, 400, errors.New("URLs must start with http:// or https://"))
+			return
+		}
+	}
+	if in.RefreshSeconds < 2 || in.RefreshSeconds > 3600 {
+		in.RefreshSeconds = 10
+	}
+	if err := s.st.SaveSettings(in); err != nil {
+		fail(w, 500, err)
+		return
+	}
+	s.getSettings(w, r)
+}
+
+// Overview is the single view: one object, each section collected independently.
+type Overview struct {
+	Time    time.Time   `json:"time"`
+	Host    Host        `json:"host"`
+	Docker  *DockerView `json:"docker"`
+	Storage *Storage    `json:"storage"`
+	Tunnels *Tunnels    `json:"tunnels"`
+	Refresh int         `json:"refreshSeconds"`
+}
+
+type DockerView struct {
+	Containers []Container `json:"containers"`
+	Error      string      `json:"error,omitempty"`
+}
+
+func (s *Server) overview(w http.ResponseWriter, r *http.Request) {
+	set := s.st.Settings()
+	ctx, cancel := context.WithTimeout(r.Context(), 20*time.Second)
+	defer cancel()
+	o := Overview{Time: time.Now(), Refresh: set.RefreshSeconds}
+	var wg sync.WaitGroup
+	run := func(f func()) { wg.Add(1); go func() { defer wg.Done(); f() }() }
+	run(func() { o.Host = CollectHost() })
+	if set.DockerHost != "" {
+		run(func() {
+			v := &DockerView{Containers: []Container{}}
+			cs, err := NewDocker(set.DockerHost).List(ctx)
+			if err != nil {
+				v.Error = err.Error()
+			} else {
+				v.Containers = cs
+			}
+			o.Docker = v
+		})
+	}
+	if (set.TrueNAS.URL != "" && set.TrueNAS.APIKey != "") || set.Smartctl {
+		run(func() {
+			st := Storage{Pools: []Pool{}, Disks: []Disk{}, Alerts: []Alert{}}
+			if set.TrueNAS.URL != "" && set.TrueNAS.APIKey != "" {
+				st = NewTrueNAS(set.TrueNAS.URL, set.TrueNAS.APIKey, set.TrueNAS.Insecure).Collect(ctx)
+			}
+			if set.Smartctl {
+				disks, err := LocalSmart(ctx, s.smart)
+				if err != nil && st.Error == "" {
+					st.Error = "smartctl: " + err.Error()
+				}
+				st.Disks = mergeDisks(st.Disks, disks)
+			}
+			o.Storage = &st
+		})
+	}
+	if set.Hammerhead.URL != "" && set.Hammerhead.APIKey != "" && set.Hammerhead.Org != "" {
+		run(func() {
+			t := FetchTunnels(ctx, set.Hammerhead.URL, set.Hammerhead.APIKey, set.Hammerhead.Org)
+			o.Tunnels = &t
+		})
+	}
+	wg.Wait()
+	writeJSON(w, 200, o)
+}
+
+// mergeDisks lets smartctl fill in what TrueNAS did not report (health, temperature) for the same device,
+// and adds disks only smartctl can see.
+func mergeDisks(tn, local []Disk) []Disk {
+	idx := map[string]int{}
+	for i, d := range tn {
+		idx[d.Serial+"|"+d.Name] = i
+		if d.Serial != "" {
+			idx[d.Serial] = i
+		}
+	}
+	for _, l := range local {
+		i, ok := -1, false
+		if l.Serial != "" {
+			i, ok = lookup(idx, l.Serial)
+		}
+		if !ok {
+			i, ok = lookup(idx, "|"+strings.TrimPrefix(l.Name, "/dev/"))
+		}
+		if !ok {
+			tn = append(tn, l)
+			continue
+		}
+		if tn[i].Health == "" {
+			tn[i].Health = l.Health
+		}
+		if tn[i].TempC == 0 {
+			tn[i].TempC = l.TempC
+		}
+	}
+	return tn
+}
+
+func lookup(m map[string]int, k string) (int, bool) { i, ok := m[k]; return i, ok }
+
+var idRe = regexp.MustCompile(`^[A-Za-z0-9_.-]{1,128}$`)
+
+func (s *Server) docker(w http.ResponseWriter, r *http.Request) (*Docker, string, bool) {
+	set := s.st.Settings()
+	id := r.PathValue("id")
+	if set.DockerHost == "" {
+		fail(w, 400, errors.New("Docker is not configured"))
+		return nil, "", false
+	}
+	if !idRe.MatchString(id) {
+		fail(w, 400, errors.New("bad container id"))
+		return nil, "", false
+	}
+	return NewDocker(set.DockerHost), id, true
+}
+
+func (s *Server) containerAction(w http.ResponseWriter, r *http.Request) {
+	d, id, ok := s.docker(w, r)
+	if !ok {
+		return
+	}
+	if err := d.Action(r.Context(), id, r.PathValue("action")); err != nil {
+		fail(w, 502, err)
+		return
+	}
+	writeJSON(w, 200, map[string]bool{"ok": true})
+}
+
+func (s *Server) containerLogs(w http.ResponseWriter, r *http.Request) {
+	d, id, ok := s.docker(w, r)
+	if !ok {
+		return
+	}
+	tail, _ := strconv.Atoi(r.URL.Query().Get("tail"))
+	out, err := d.Logs(r.Context(), id, tail)
+	if err != nil {
+		fail(w, 502, err)
+		return
+	}
+	writeJSON(w, 200, map[string]string{"logs": out})
+}

internal/beach/server_test.go

@@ -0,0 +1,137 @@
+package beach
+
+import (
+	"encoding/json"
+	"io"
+	"net/http"
+	"net/http/cookiejar"
+	"net/http/httptest"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+type client struct {
+	t *testing.T
+	c *http.Client
+	u string
+}
+
+func newClient(t *testing.T) (*client, *Store) {
+	st, err := OpenStore(filepath.Join(t.TempDir(), "beach.db"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	t.Cleanup(func() { st.Close() })
+	ts := httptest.NewServer(NewServer(st))
+	t.Cleanup(ts.Close)
+	jar, _ := cookiejar.New(nil)
+	return &client{t, &http.Client{Jar: jar}, ts.URL}, st
+}
+
+func (c *client) do(method, path, body string, hdr bool) (int, map[string]any) {
+	req, _ := http.NewRequest(method, c.u+path, strings.NewReader(body))
+	if hdr {
+		req.Header.Set("X-Beach", "1")
+	}
+	resp, err := c.c.Do(req)
+	if err != nil {
+		c.t.Fatal(err)
+	}
+	defer resp.Body.Close()
+	b, _ := io.ReadAll(resp.Body)
+	var m map[string]any
+	json.Unmarshal(b, &m)
+	return resp.StatusCode, m
+}
+
+func TestAuthFlow(t *testing.T) {
+	c, _ := newClient(t)
+	if code, _ := c.do("GET", "/api/overview", "", false); code != 401 {
+		t.Fatalf("overview without a session: %d", code)
+	}
+	if code, _ := c.do("POST", "/api/setup", `{"name":"a","password":"longenough"}`, false); code != 403 {
+		t.Fatalf("writes without X-Beach must be refused, got %d", code)
+	}
+	if code, _ := c.do("POST", "/api/setup", `{"name":"a","password":"short"}`, true); code != 400 {
+		t.Fatalf("short password: %d", code)
+	}
+	if _, m := c.do("GET", "/api/session", "", false); m["setup"] != true {
+		t.Fatalf("fresh install should ask for setup: %v", m)
+	}
+	if code, _ := c.do("POST", "/api/setup", `{"name":"alex","password":"longenough"}`, true); code != 200 {
+		t.Fatalf("setup: %d", code)
+	}
+	if code, _ := c.do("POST", "/api/setup", `{"name":"eve","password":"longenough"}`, true); code != 409 {
+		t.Fatalf("second setup must be refused, got %d", code)
+	}
+	if code, m := c.do("GET", "/api/overview", "", false); code != 200 || m["host"] == nil {
+		t.Fatalf("overview after setup: %d %v", code, m)
+	}
+	c.do("POST", "/api/logout", "", true)
+	if code, _ := c.do("GET", "/api/overview", "", false); code != 401 {
+		t.Fatal("logout should end the session")
+	}
+	if code, _ := c.do("POST", "/api/login", `{"name":"alex","password":"wrongwrong"}`, true); code != 401 {
+		t.Fatalf("bad password: %d", code)
+	}
+	if code, _ := c.do("POST", "/api/login", `{"name":"alex","password":"longenough"}`, true); code != 200 {
+		t.Fatalf("login: %d", code)
+	}
+}
+
+func TestLoginRateLimit(t *testing.T) {
+	c, _ := newClient(t)
+	c.do("POST", "/api/setup", `{"name":"alex","password":"longenough"}`, true)
+	c.do("POST", "/api/logout", "", true)
+	var last int
+	for i := 0; i < 9; i++ {
+		last, _ = c.do("POST", "/api/login", `{"name":"alex","password":"nope-nope"}`, true)
+	}
+	if last != 429 {
+		t.Fatalf("expected lockout after repeated failures, got %d", last)
+	}
+	if code, _ := c.do("POST", "/api/login", `{"name":"alex","password":"longenough"}`, true); code != 429 {
+		t.Fatalf("lockout should hold even for the right password, got %d", code)
+	}
+}
+
+func TestSettingsKeepSecrets(t *testing.T) {
+	c, st := newClient(t)
+	c.do("POST", "/api/setup", `{"name":"alex","password":"longenough"}`, true)
+	body := `{"dockerHost":"","truenas":{"url":"https://nas","apiKey":"k1"},"hammerhead":{"url":"https://hh","org":"o","apiKey":"k2"},"refreshSeconds":5}`
+	code, m := c.do("PUT", "/api/settings", body, true)
+	if code != 200 || m["truenasKeySet"] != true || m["hammerheadKeySet"] != true {
+		t.Fatalf("%d %v", code, m)
+	}
+	if tn := m["truenas"].(map[string]any); tn["apiKey"] != "" {
+		t.Fatal("API key must never be sent back to the browser")
+	}
+	// saving again with blank key boxes keeps the stored keys
+	c.do("PUT", "/api/settings", `{"dockerHost":"","truenas":{"url":"https://nas","apiKey":""},"hammerhead":{"url":"https://hh","org":"o","apiKey":""},"refreshSeconds":5}`, true)
+	if s := st.Settings(); s.TrueNAS.APIKey != "k1" || s.Hammerhead.APIKey != "k2" {
+		t.Fatalf("keys lost: %+v", s)
+	}
+	if code, _ := c.do("PUT", "/api/settings", `{"truenas":{"url":"ftp://x"}}`, true); code != 400 {
+		t.Fatalf("bad URL scheme accepted: %d", code)
+	}
+}
+
+func TestOverviewSectionsFollowSettings(t *testing.T) {
+	c, _ := newClient(t)
+	c.do("POST", "/api/setup", `{"name":"alex","password":"longenough"}`, true)
+	c.do("PUT", "/api/settings", `{"dockerHost":"","refreshSeconds":10}`, true)
+	_, m := c.do("GET", "/api/overview", "", false)
+	if m["docker"] != nil || m["storage"] != nil || m["tunnels"] != nil {
+		t.Fatalf("unconfigured sections must be absent: %v", m)
+	}
+	c.do("PUT", "/api/settings", `{"dockerHost":"127.0.0.1:1","refreshSeconds":10}`, true)
+	_, m = c.do("GET", "/api/overview", "", false)
+	d, _ := m["docker"].(map[string]any)
+	if d == nil || d["error"] == nil {
+		t.Fatalf("unreachable Docker should show an error, not break the page: %v", m)
+	}
+	if code, _ := c.do("POST", "/api/containers/..%2Fx/start", "", true); code != 400 && code != 404 {
+		t.Fatalf("path tricks in container id: %d", code)
+	}
+}

internal/beach/smart.go

@@ -0,0 +1,85 @@
+package beach
+
+import (
+	"context"
+	"encoding/json"
+	"os/exec"
+	"sort"
+	"time"
+)
+
+// parseSmartctl reads `smartctl -j -H -i -A` output for one device.
+func parseSmartctl(b []byte) (Disk, error) {
+	var r struct {
+		Device struct {
+			Name string `json:"name"`
+		} `json:"device"`
+		ModelName    string `json:"model_name"`
+		SerialNumber string `json:"serial_number"`
+		UserCapacity struct {
+			Bytes int64 `json:"bytes"`
+		} `json:"user_capacity"`
+		SmartStatus struct {
+			Passed *bool `json:"passed"`
+		} `json:"smart_status"`
+		Temperature struct {
+			Current float64 `json:"current"`
+		} `json:"temperature"`
+	}
+	if err := json.Unmarshal(b, &r); err != nil {
+		return Disk{}, err
+	}
+	d := Disk{Name: r.Device.Name, Model: r.ModelName, Serial: r.SerialNumber, Size: r.UserCapacity.Bytes, TempC: r.Temperature.Current, Source: "smartctl"}
+	if r.SmartStatus.Passed != nil {
+		d.Health = "FAILED"
+		if *r.SmartStatus.Passed {
+			d.Health = "PASSED"
+		}
+	}
+	return d, nil
+}
+
+// runner lets tests replace the smartctl binary.
+type runner func(ctx context.Context, args ...string) ([]byte, error)
+
+func execSmartctl(ctx context.Context, args ...string) ([]byte, error) {
+	// smartctl uses non-zero exit bits to report problems; the JSON is still valid
+	out, err := exec.CommandContext(ctx, "smartctl", args...).Output()
+	if len(out) > 0 {
+		return out, nil
+	}
+	return out, err
+}
+
+// LocalSmart scans for devices and reads each one.
+func LocalSmart(ctx context.Context, run runner) ([]Disk, error) {
+	ctx, cancel := context.WithTimeout(ctx, 20*time.Second)
+	defer cancel()
+	b, err := run(ctx, "--scan", "-j")
+	if err != nil {
+		return nil, err
+	}
+	var scan struct {
+		Devices []struct {
+			Name string `json:"name"`
+		} `json:"devices"`
+	}
+	if err := json.Unmarshal(b, &scan); err != nil {
+		return nil, err
+	}
+	out := []Disk{}
+	for _, dev := range scan.Devices {
+		b, err := run(ctx, "-j", "-H", "-i", "-A", dev.Name)
+		if err != nil {
+			continue
+		}
+		if d, err := parseSmartctl(b); err == nil {
+			if d.Name == "" {
+				d.Name = dev.Name
+			}
+			out = append(out, d)
+		}
+	}
+	sort.Slice(out, func(i, j int) bool { return out[i].Name < out[j].Name })
+	return out, nil
+}

internal/beach/store.go

@@ -0,0 +1,124 @@
+package beach
+
+import (
+	"crypto/rand"
+	"crypto/sha256"
+	"database/sql"
+	"encoding/hex"
+	"encoding/json"
+	"errors"
+	"time"
+
+	_ "modernc.org/sqlite"
+)
+
+// Store is Beach's one SQLite file (pure Go, WAL mode). Settings are a single
+// JSON document, so everything is edited in the web UI and there is no config file.
+type Store struct{ db *sql.DB }
+
+const schema = `
+CREATE TABLE IF NOT EXISTS settings (id INTEGER PRIMARY KEY CHECK (id = 1), body TEXT NOT NULL);
+CREATE TABLE IF NOT EXISTS users (name TEXT PRIMARY KEY, hash TEXT NOT NULL);
+CREATE TABLE IF NOT EXISTS sessions (hash TEXT PRIMARY KEY, user TEXT NOT NULL, expires INTEGER NOT NULL);
+`
+
+// Settings is everything configurable. Empty sections are simply not collected.
+type Settings struct {
+	DockerHost string `json:"dockerHost"` // unix socket path, or tcp://host:2375; empty disables Docker
+	TrueNAS    struct {
+		URL      string `json:"url"`
+		APIKey   string `json:"apiKey"`
+		Insecure bool   `json:"insecure"` // accept a self-signed certificate
+	} `json:"truenas"`
+	Smartctl   bool `json:"smartctl"` // also read SMART from local smartctl
+	Hammerhead struct {
+		URL    string `json:"url"`
+		APIKey string `json:"apiKey"`
+		Org    string `json:"org"`
+	} `json:"hammerhead"`
+	RefreshSeconds int `json:"refreshSeconds"`
+}
+
+func OpenStore(path string) (*Store, error) {
+	db, err := sql.Open("sqlite", path+"?_pragma=journal_mode(WAL)&_pragma=busy_timeout(5000)")
+	if err != nil {
+		return nil, err
+	}
+	db.SetMaxOpenConns(1)
+	if _, err := db.Exec(schema); err != nil {
+		return nil, err
+	}
+	return &Store{db}, nil
+}
+
+func (s *Store) Close() error { return s.db.Close() }
+
+func (s *Store) Settings() Settings {
+	var set Settings
+	var body string
+	if s.db.QueryRow(`SELECT body FROM settings WHERE id=1`).Scan(&body) == nil {
+		_ = json.Unmarshal([]byte(body), &set)
+	} else {
+		set.DockerHost = defaultDockerHost
+	}
+	if set.RefreshSeconds < 2 {
+		set.RefreshSeconds = 10
+	}
+	return set
+}
+
+func (s *Store) SaveSettings(set Settings) error {
+	b, _ := json.Marshal(set)
+	_, err := s.db.Exec(`INSERT INTO settings (id, body) VALUES (1, ?) ON CONFLICT(id) DO UPDATE SET body=excluded.body`, string(b))
+	return err
+}
+
+func (s *Store) HasUsers() bool {
+	var n int
+	s.db.QueryRow(`SELECT COUNT(*) FROM users`).Scan(&n)
+	return n > 0
+}
+
+func (s *Store) AddUser(name, hash string) error {
+	_, err := s.db.Exec(`INSERT INTO users (name, hash) VALUES (?, ?)`, name, hash)
+	return err
+}
+
+func (s *Store) UserHash(name string) (string, bool) {
+	var h string
+	err := s.db.QueryRow(`SELECT hash FROM users WHERE name=?`, name).Scan(&h)
+	return h, err == nil
+}
+
+func hashToken(t string) string {
+	h := sha256.Sum256([]byte(t))
+	return hex.EncodeToString(h[:])
+}
+
+// NewSession returns a random token; only its hash is stored.
+func (s *Store) NewSession(user string, ttl time.Duration) (string, error) {
+	b := make([]byte, 32)
+	if _, err := rand.Read(b); err != nil {
+		return "", err
+	}
+	tok := hex.EncodeToString(b)
+	_, err := s.db.Exec(`INSERT INTO sessions (hash, user, expires) VALUES (?, ?, ?)`, hashToken(tok), user, time.Now().Add(ttl).Unix())
+	return tok, err
+}
+
+func (s *Store) SessionUser(tok string) (string, error) {
+	var u string
+	var exp int64
+	if err := s.db.QueryRow(`SELECT user, expires FROM sessions WHERE hash=?`, hashToken(tok)).Scan(&u, &exp); err != nil {
+		return "", err
+	}
+	if time.Now().Unix() > exp {
+		s.DeleteSession(tok)
+		return "", errors.New("expired")
+	}
+	return u, nil
+}
+
+func (s *Store) DeleteSession(tok string) {
+	s.db.Exec(`DELETE FROM sessions WHERE hash=?`, hashToken(tok))
+}

internal/beach/truenas.go

@@ -0,0 +1,187 @@
+package beach
+
+import (
+	"context"
+	"crypto/tls"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"sort"
+	"strings"
+	"time"
+)
+
+// Pool is a ZFS pool as TrueNAS reports it.
+type Pool struct {
+	Name      string  `json:"name"`
+	Status    string  `json:"status"` // ONLINE, DEGRADED, ...
+	Healthy   bool    `json:"healthy"`
+	Size      int64   `json:"size"`
+	Allocated int64   `json:"allocated"`
+	UsedPct   float64 `json:"usedPct"`
+	Scan      string  `json:"scan"` // "scrub finished, 0 errors" or "scrub in progress 41%"
+	Errors    int     `json:"errors"`
+}
+
+// Disk is a physical disk with its SMART verdict.
+type Disk struct {
+	Name   string  `json:"name"`
+	Model  string  `json:"model"`
+	Serial string  `json:"serial"`
+	Size   int64   `json:"size"`
+	Pool   string  `json:"pool,omitempty"`
+	TempC  float64 `json:"tempC"`  // 0 when unknown
+	Health string  `json:"health"` // PASSED, FAILED or "" when unknown
+	Source string  `json:"source"` // truenas or smartctl
+}
+
+type Alert struct {
+	Level   string `json:"level"`
+	Message string `json:"message"`
+}
+
+type Storage struct {
+	Pools  []Pool  `json:"pools"`
+	Disks  []Disk  `json:"disks"`
+	Alerts []Alert `json:"alerts"`
+	Error  string  `json:"error,omitempty"`
+}
+
+// TrueNAS reads the v2.0 REST API with an API key.
+type TrueNAS struct {
+	base   string
+	key    string
+	client *http.Client
+}
+
+func NewTrueNAS(base, key string, insecure bool) *TrueNAS {
+	tr := &http.Transport{}
+	if insecure {
+		tr.TLSClientConfig = &tls.Config{InsecureSkipVerify: true}
+	}
+	return &TrueNAS{base: strings.TrimRight(base, "/"), key: key, client: &http.Client{Transport: tr, Timeout: 15 * time.Second}}
+}
+
+func (t *TrueNAS) call(ctx context.Context, method, path string, body io.Reader, out any) error {
+	req, err := http.NewRequestWithContext(ctx, method, t.base+"/api/v2.0"+path, body)
+	if err != nil {
+		return err
+	}
+	req.Header.Set("Authorization", "Bearer "+t.key)
+	if body != nil {
+		req.Header.Set("Content-Type", "application/json")
+	}
+	resp, err := t.client.Do(req)
+	if err != nil {
+		return err
+	}
+	defer resp.Body.Close()
+	b, _ := io.ReadAll(io.LimitReader(resp.Body, 16<<20))
+	if resp.StatusCode == 401 || resp.StatusCode == 403 {
+		return fmt.Errorf("truenas: API key rejected (%s)", resp.Status)
+	}
+	if resp.StatusCode >= 300 {
+		return fmt.Errorf("truenas %s: %s", path, resp.Status)
+	}
+	return json.Unmarshal(b, out)
+}
+
+// Collect gathers pools, disks, temperatures and alerts. A failing secondary
+// endpoint degrades the result instead of failing the whole panel.
+func (t *TrueNAS) Collect(ctx context.Context) Storage {
+	st := Storage{Pools: []Pool{}, Disks: []Disk{}, Alerts: []Alert{}}
+	var pools []map[string]any
+	if err := t.call(ctx, "GET", "/pool", nil, &pools); err != nil {
+		st.Error = err.Error()
+		return st
+	}
+	st.Pools = parsePools(pools)
+	var disks []map[string]any
+	if err := t.call(ctx, "GET", "/disk", nil, &disks); err == nil {
+		st.Disks = parseDisks(disks)
+	} else {
+		st.Error = err.Error()
+	}
+	var temps map[string]*float64
+	if err := t.call(ctx, "POST", "/disk/temperatures", strings.NewReader(`{}`), &temps); err == nil {
+		for i := range st.Disks {
+			if v := temps[st.Disks[i].Name]; v != nil {
+				st.Disks[i].TempC = *v
+			}
+		}
+	}
+	var alerts []map[string]any
+	if err := t.call(ctx, "GET", "/alert/list", nil, &alerts); err == nil {
+		st.Alerts = parseAlerts(alerts)
+	}
+	return st
+}
+
+func str(m map[string]any, k string) string {
+	if v, ok := m[k].(string); ok {
+		return v
+	}
+	return ""
+}
+
+func num(m map[string]any, k string) float64 {
+	switch v := m[k].(type) {
+	case float64:
+		return v
+	case map[string]any: // some fields come as {"parsed": n, "rawvalue": "n"}
+		if p, ok := v["parsed"].(float64); ok {
+			return p
+		}
+	}
+	return 0
+}
+
+func parsePools(in []map[string]any) []Pool {
+	out := []Pool{}
+	for _, m := range in {
+		p := Pool{Name: str(m, "name"), Status: str(m, "status"), Size: int64(num(m, "size")), Allocated: int64(num(m, "allocated"))}
+		p.Healthy, _ = m["healthy"].(bool)
+		if p.Size > 0 {
+			p.UsedPct = float64(p.Allocated) / float64(p.Size) * 100
+		}
+		if scan, ok := m["scan"].(map[string]any); ok {
+			p.Errors = int(num(scan, "errors"))
+			fn := strings.ToLower(str(scan, "function"))
+			state := strings.ToLower(str(scan, "state"))
+			switch {
+			case state == "scanning":
+				p.Scan = fmt.Sprintf("%s in progress %.0f%%", fn, num(scan, "percentage"))
+			case state != "":
+				p.Scan = fmt.Sprintf("%s %s, %d errors", fn, state, p.Errors)
+			}
+		}
+		out = append(out, p)
+	}
+	sort.Slice(out, func(i, j int) bool { return out[i].Name < out[j].Name })
+	return out
+}
+
+func parseDisks(in []map[string]any) []Disk {
+	out := []Disk{}
+	for _, m := range in {
+		out = append(out, Disk{Name: str(m, "name"), Model: str(m, "model"), Serial: str(m, "serial"), Size: int64(num(m, "size")), Pool: str(m, "pool"), Source: "truenas"})
+	}
+	sort.Slice(out, func(i, j int) bool { return out[i].Name < out[j].Name })
+	return out
+}
+
+func parseAlerts(in []map[string]any) []Alert {
+	out := []Alert{}
+	for _, m := range in {
+		if dismissed, _ := m["dismissed"].(bool); dismissed {
+			continue
+		}
+		msg := str(m, "formatted")
+		if msg == "" {
+			msg = str(m, "klass")
+		}
+		out = append(out, Alert{Level: str(m, "level"), Message: msg})
+	}
+	return out
+}

internal/beach/web/index.html

@@ -0,0 +1,229 @@
+<!doctype html>
+<html lang="en">
+<head>
+<meta charset="utf-8">
+<meta name="viewport" content="width=device-width, initial-scale=1">
+<title>Beach</title>
+<link rel="icon" href="data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 32 32'%3E%3Ccircle cx='16' cy='16' r='14' fill='%23e9b44c'/%3E%3C/svg%3E">
+<style>
+:root{--bg:#f6f4ef;--card:#fff;--fg:#1d2327;--mut:#6b7378;--line:#e3dfd5;--ok:#1f8a4c;--warn:#b7791f;--bad:#c53030;--acc:#0e6e8c}
+@media (prefers-color-scheme:dark){:root{--bg:#14181b;--card:#1d2226;--fg:#e8eaeb;--mut:#8d979c;--line:#2d3439;--ok:#4ac17c;--warn:#e0a84a;--bad:#f06a6a;--acc:#4fb3d1}}
+*{box-sizing:border-box}
+body{margin:0;background:var(--bg);color:var(--fg);font:14px/1.45 system-ui,sans-serif}
+header{display:flex;align-items:center;gap:12px;padding:12px 20px;border-bottom:1px solid var(--line);background:var(--card);position:sticky;top:0;z-index:2}
+header h1{font-size:18px;margin:0;flex:1}
+main{max-width:1200px;margin:0 auto;padding:16px 20px 60px;display:grid;gap:16px}
+section{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:14px 16px;overflow-x:auto}
+section h2{font-size:13px;text-transform:uppercase;letter-spacing:.06em;color:var(--mut);margin:0 0 10px;display:flex;gap:8px;align-items:center}
+table{border-collapse:collapse;width:100%}
+th,td{text-align:left;padding:6px 8px;border-bottom:1px solid var(--line);white-space:nowrap}
+th{color:var(--mut);font-weight:500;font-size:12px}
+tr:last-child td{border-bottom:0}
+.dot{display:inline-block;width:9px;height:9px;border-radius:50%;margin-right:6px;background:var(--mut)}
+.ok{background:var(--ok)}.warn{background:var(--warn)}.bad{background:var(--bad)}
+.t-ok{color:var(--ok)}.t-warn{color:var(--warn)}.t-bad{color:var(--bad)}.mut{color:var(--mut)}
+button{font:inherit;border:1px solid var(--line);background:var(--card);color:var(--fg);border-radius:6px;padding:3px 10px;cursor:pointer}
+button:hover{border-color:var(--acc)}button.primary{background:var(--acc);color:#fff;border-color:var(--acc)}
+input[type=text],input[type=password],input[type=url],input[type=number]{font:inherit;width:100%;padding:6px 8px;border:1px solid var(--line);border-radius:6px;background:var(--bg);color:var(--fg)}
+.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:12px}
+.stat .v{font-size:22px;font-weight:600}.stat .l{color:var(--mut);font-size:12px}
+.bar{height:6px;background:var(--line);border-radius:3px;overflow:hidden;margin-top:4px}.bar i{display:block;height:100%;background:var(--acc)}
+.bar i.warn{background:var(--warn)}.bar i.bad{background:var(--bad)}
+.err{color:var(--bad);font-size:13px;margin:4px 0}
+.cols{display:grid;grid-template-columns:1fr 1fr;gap:16px}@media(max-width:800px){.cols{grid-template-columns:1fr}}
+dialog{border:1px solid var(--line);border-radius:10px;background:var(--card);color:var(--fg);width:min(900px,94vw);padding:16px}
+dialog::backdrop{background:#0008}
+pre{background:var(--bg);padding:10px;border-radius:6px;max-height:60vh;overflow:auto;font-size:12px;white-space:pre-wrap;word-break:break-all}
+label{display:block;margin:10px 0 3px;color:var(--mut);font-size:12px}
+.login{max-width:340px;margin:12vh auto;background:var(--card);border:1px solid var(--line);border-radius:10px;padding:20px}
+.hide{display:none!important}
+</style>
+</head>
+<body>
+<div id="auth" class="login hide">
+  <h1 id="authTitle" style="margin-top:0">Beach</h1>
+  <p class="mut" id="authHint"></p>
+  <label>Name</label><input type="text" id="aName" autocomplete="username">
+  <label>Password</label><input type="password" id="aPass" autocomplete="current-password">
+  <p class="err" id="aErr"></p>
+  <button class="primary" id="aGo"></button>
+</div>
+
+<div id="app" class="hide">
+<header>
+  <h1>🏖 Beach <span class="mut" id="hostName" style="font-weight:400;font-size:13px"></span></h1>
+  <span class="mut" id="updated"></span>
+  <button id="btnSettings">Settings</button>
+  <button id="btnLogout">Sign out</button>
+</header>
+<main>
+  <section id="hostSec"><h2>Host</h2><div class="grid" id="hostStats"></div></section>
+  <section id="dockerSec"><h2>Containers <span id="dockerCount" class="mut"></span></h2><div id="dockerBody"></div></section>
+  <div class="cols">
+    <section id="poolSec"><h2>Pools</h2><div id="poolBody"></div></section>
+    <section id="tunnelSec"><h2>Tunnels &amp; sites</h2><div id="tunnelBody"></div></section>
+  </div>
+  <section id="diskSec"><h2>Disks &amp; SMART</h2><div id="diskBody"></div></section>
+</main>
+</div>
+
+<dialog id="logDlg"><h2 id="logTitle" style="margin-top:0"></h2><pre id="logBody"></pre><button id="logClose">Close</button> <button id="logReload">Reload</button></dialog>
+
+<dialog id="setDlg">
+  <h2 style="margin-top:0">Settings</h2>
+  <label>Docker (socket path, or tcp://host:2375 — empty turns Docker off)</label><input type="text" id="sDocker">
+  <div class="cols">
+    <div>
+      <h3>TrueNAS</h3>
+      <label>URL</label><input type="url" id="sTnUrl" placeholder="https://truenas.local">
+      <label>API key <span id="sTnSet" class="mut"></span></label><input type="password" id="sTnKey" autocomplete="off" placeholder="leave blank to keep">
+      <label><input type="checkbox" id="sTnInsecure"> Accept a self-signed certificate</label>
+      <label><input type="checkbox" id="sSmart"> Also read SMART from local <code>smartctl</code></label>
+    </div>
+    <div>
+      <h3>Hammerhead</h3>
+      <label>URL</label><input type="url" id="sHhUrl" placeholder="https://hammerhead.example.com">
+      <label>Organization ID</label><input type="text" id="sHhOrg">
+      <label>API key <span id="sHhSet" class="mut"></span></label><input type="password" id="sHhKey" autocomplete="off" placeholder="leave blank to keep">
+    </div>
+  </div>
+  <label>Refresh every (seconds)</label><input type="number" id="sRefresh" min="2" max="3600" style="width:100px">
+  <p class="err" id="sErr"></p>
+  <button class="primary" id="sSave">Save</button> <button id="sCancel">Cancel</button>
+</dialog>
+
+<script>
+const $ = id => document.getElementById(id);
+let timer = null, logId = null;
+
+async function api(method, path, body) {
+  const r = await fetch(path, {method, headers: {'X-Beach': '1', 'Content-Type': 'application/json'}, body: body ? JSON.stringify(body) : undefined});
+  const j = await r.json().catch(() => ({}));
+  if (r.status === 401 && path !== '/api/login') { showAuth(false); throw new Error(j.error || 'signed out'); }
+  if (!r.ok) throw new Error(j.error || r.statusText);
+  return j;
+}
+
+const esc = s => String(s ?? '').replace(/[&<>"']/g, c => ({'&':'&amp;','<':'&lt;','>':'&gt;','"':'&quot;',"'":'&#39;'}[c]));
+function bytes(n) { if (!n) return '0 B'; const u = ['B','KB','MB','GB','TB','PB']; let i = Math.min(5, Math.floor(Math.log(n) / Math.log(1024))); return (n / 1024 ** i).toFixed(i > 1 ? 1 : 0) + ' ' + u[i]; }
+function dur(s) { s = Math.floor(s); const d = Math.floor(s / 86400), h = Math.floor(s % 86400 / 3600), m = Math.floor(s % 3600 / 60); return d ? `${d}d ${h}h` : h ? `${h}h ${m}m` : `${m}m`; }
+const dot = c => `<span class="dot ${c}"></span>`;
+function bar(p) { p = Math.max(0, Math.min(100, p)); return `<div class="bar"><i class="${p > 90 ? 'bad' : p > 75 ? 'warn' : ''}" style="width:${p}%"></i></div>`; }
+function stat(l, v, p) { return `<div class="stat"><div class="l">${esc(l)}</div><div class="v">${v}</div>${p == null ? '' : bar(p)}</div>`; }
+
+function showAuth(setup) {
+  $('app').classList.add('hide'); $('auth').classList.remove('hide');
+  clearTimeout(timer);
+  $('authTitle').textContent = setup ? 'Welcome to Beach' : 'Sign in';
+  $('authHint').textContent = setup ? 'Create the administrator account.' : '';
+  $('aGo').textContent = setup ? 'Create account' : 'Sign in';
+  $('aGo').onclick = async () => {
+    $('aErr').textContent = '';
+    try { await api('POST', setup ? '/api/setup' : '/api/login', {name: $('aName').value, password: $('aPass').value}); $('aPass').value = ''; start(); }
+    catch (e) { $('aErr').textContent = e.message; }
+  };
+}
+
+async function start() {
+  const s = await api('GET', '/api/session');
+  if (!s.user) return showAuth(s.setup);
+  $('auth').classList.add('hide'); $('app').classList.remove('hide');
+  refresh();
+}
+
+async function refresh() {
+  clearTimeout(timer);
+  let o;
+  try { o = await api('GET', '/api/overview'); } catch (e) { $('updated').textContent = e.message; timer = setTimeout(refresh, 15000); return; }
+  render(o);
+  $('updated').textContent = 'Updated ' + new Date(o.time).toLocaleTimeString();
+  timer = setTimeout(refresh, o.refreshSeconds * 1000);
+}
+
+function render(o) {
+  const h = o.host;
+  $('hostName').textContent = h.hostname || '';
+  if (!h.supported) $('hostStats').innerHTML = '<span class="mut">Host metrics are only collected on Linux.</span>';
+  else {
+    const memP = h.memTotal ? h.memUsed / h.memTotal * 100 : 0;
+    let s = stat('CPU', h.cpuPct.toFixed(0) + '%', h.cpuPct) + stat('Memory', `${bytes(h.memUsed)} / ${bytes(h.memTotal)}`, memP)
+      + stat('Load', h.load.map(x => x.toFixed(2)).join(' · '), Math.min(100, h.load[0] / h.cpus * 100)) + stat('Uptime', dur(h.uptimeSeconds));
+    if (h.swapTotal) s += stat('Swap', `${bytes(h.swapUsed)} / ${bytes(h.swapTotal)}`, h.swapUsed / h.swapTotal * 100);
+    for (const f of h.filesystems) s += stat(f.mount, `${bytes(f.used)} / ${bytes(f.total)}`, f.used / f.total * 100);
+    $('hostStats').innerHTML = s;
+  }
+
+  const d = o.docker;
+  $('dockerSec').classList.toggle('hide', !d);
+  if (d) {
+    const run = d.containers.filter(c => c.state === 'running').length;
+    $('dockerCount').textContent = d.error ? '' : `${run} running / ${d.containers.length}`;
+    $('dockerBody').innerHTML = (d.error ? `<div class="err">${esc(d.error)}</div>` : '') + (d.containers.length ? `<table><tr><th>Name</th><th>Image</th><th>Status</th><th>Ports</th><th></th></tr>${d.containers.map(c => {
+      const up = c.state === 'running', bad = /unhealthy/.test(c.status) || c.state === 'dead';
+      return `<tr><td>${dot(bad ? 'bad' : up ? 'ok' : '')}${esc(c.name)}</td><td class="mut">${esc(c.image)}</td><td>${esc(c.status)}</td><td class="mut">${esc(c.ports.join(', '))}</td>
+        <td>${up ? `<button data-a="stop" data-id="${esc(c.id)}">Stop</button> <button data-a="restart" data-id="${esc(c.id)}">Restart</button>` : `<button data-a="start" data-id="${esc(c.id)}">Start</button>`} <button data-a="logs" data-id="${esc(c.id)}" data-n="${esc(c.name)}">Logs</button></td></tr>`;
+    }).join('')}</table>` : d.error ? '' : '<span class="mut">No containers.</span>');
+  }
+
+  const s = o.storage;
+  $('poolSec').classList.toggle('hide', !s); $('diskSec').classList.toggle('hide', !s);
+  if (s) {
+    $('poolBody').innerHTML = (s.error ? `<div class="err">${esc(s.error)}</div>` : '')
+      + s.pools.map(p => `<div style="margin-bottom:10px">${dot(p.healthy ? 'ok' : p.status === 'ONLINE' ? 'warn' : 'bad')}<b>${esc(p.name)}</b> <span class="${p.healthy ? 't-ok' : 't-bad'}">${esc(p.status)}</span> <span class="mut">${bytes(p.allocated)} / ${bytes(p.size)}</span>${bar(p.usedPct)}<div class="mut">${esc(p.scan || 'never scrubbed')}</div></div>`).join('')
+      + s.alerts.map(a => `<div class="t-warn">⚠ ${esc(a.level)}: ${esc(a.message)}</div>`).join('');
+    $('diskBody').innerHTML = s.disks.length ? `<table><tr><th>Disk</th><th>Model</th><th>Serial</th><th>Size</th><th>Pool</th><th>Temp</th><th>SMART</th></tr>${s.disks.map(k => {
+      const hc = k.health === 'PASSED' ? 'ok' : k.health ? 'bad' : '', tc = k.tempC >= 55 ? 'bad' : k.tempC >= 45 ? 'warn' : '';
+      return `<tr><td>${esc(k.name)}</td><td>${esc(k.model)}</td><td class="mut">${esc(k.serial)}</td><td>${bytes(k.size)}</td><td>${esc(k.pool || '')}</td><td class="${tc && 't-' + tc}">${k.tempC ? k.tempC + ' °C' : '–'}</td><td>${dot(hc)}${esc(k.health || 'unknown')}</td></tr>`;
+    }).join('')}</table>` : '<span class="mut">No disks reported.</span>';
+  }
+
+  const t = o.tunnels;
+  $('tunnelSec').classList.toggle('hide', !t);
+  if (t) {
+    $('tunnelBody').innerHTML = (t.error ? `<div class="err">${esc(t.error)}</div>` : '')
+      + `<table>${t.sites.map(x => `<tr><td>${dot(x.online ? 'ok' : 'bad')}${esc(x.name)}${x.local ? ' <span class="mut">(edge-local)</span>' : ''}</td><td class="mut">${esc(x.version || '')}</td><td>${x.online ? 'online' : 'offline'}</td></tr>`).join('')}
+      ${t.ports.map(p => `<tr><td>${dot(!p.enabled ? '' : p.up ? 'ok' : 'bad')}${esc(p.name)}</td><td class="mut">${esc(p.hostname || p.proto + ':' + p.port)}</td><td>${!p.enabled ? 'disabled' : p.up ? `up${p.targets ? ` · ${p.healthy}/${p.targets} healthy` : ''}` : 'down'}</td></tr>`).join('')}</table>`;
+  }
+}
+
+$('dockerBody').addEventListener('click', async e => {
+  const b = e.target.closest('button'); if (!b) return;
+  const {a, id} = b.dataset;
+  if (a === 'logs') return openLogs(id, b.dataset.n);
+  b.disabled = true;
+  try { await api('POST', `/api/containers/${encodeURIComponent(id)}/${a}`); } catch (err) { alert(err.message); }
+  refresh();
+});
+
+async function openLogs(id, name) {
+  logId = id; $('logTitle').textContent = name + ' — last 200 lines';
+  if (!$('logDlg').open) $('logDlg').showModal();
+  $('logBody').textContent = 'Loading…';
+  try { $('logBody').textContent = (await api('GET', `/api/containers/${encodeURIComponent(id)}/logs?tail=200`)).logs || '(empty)'; } catch (e) { $('logBody').textContent = e.message; }
+  $('logBody').scrollTop = 1e9;
+}
+$('logClose').onclick = () => $('logDlg').close();
+$('logReload').onclick = () => openLogs(logId, $('logTitle').textContent.split(' — ')[0]);
+
+$('btnLogout').onclick = async () => { await api('POST', '/api/logout').catch(() => {}); start(); };
+$('btnSettings').onclick = async () => {
+  const s = await api('GET', '/api/settings');
+  $('sDocker').value = s.dockerHost; $('sTnUrl').value = s.truenas.url; $('sTnInsecure').checked = s.truenas.insecure; $('sSmart').checked = s.smartctl;
+  $('sHhUrl').value = s.hammerhead.url; $('sHhOrg').value = s.hammerhead.org; $('sRefresh').value = s.refreshSeconds;
+  $('sTnKey').value = $('sHhKey').value = ''; $('sTnSet').textContent = s.truenasKeySet ? '(saved)' : ''; $('sHhSet').textContent = s.hammerheadKeySet ? '(saved)' : '';
+  $('sErr').textContent = ''; $('setDlg').showModal();
+};
+$('sCancel').onclick = () => $('setDlg').close();
+$('sSave').onclick = async () => {
+  try {
+    await api('PUT', '/api/settings', {dockerHost: $('sDocker').value.trim(), smartctl: $('sSmart').checked, refreshSeconds: +$('sRefresh').value,
+      truenas: {url: $('sTnUrl').value.trim(), apiKey: $('sTnKey').value, insecure: $('sTnInsecure').checked},
+      hammerhead: {url: $('sHhUrl').value.trim(), org: $('sHhOrg').value.trim(), apiKey: $('sHhKey').value}});
+    $('setDlg').close(); refresh();
+  } catch (e) { $('sErr').textContent = e.message; }
+};
+['aName', 'aPass'].forEach(i => $(i).addEventListener('keydown', e => { if (e.key === 'Enter') $('aGo').click(); }));
+start();
+</script>
+</body>
+</html>