Server: rewrite in Go as an API-only service

Same endpoints, request formats, validation rules and InfluxDB layout as the Next.js server, so the car needs no change: POST /v1/telemetry, PUT /v1/consumption/daily, PUT /v1/charging-sessions/{id}, GET /v1/consumption/history/{id}, GET /v1/health. The dashboard, login and the /v1/history reads are gone; Grafana takes over the dashboards. - Go 1.26 standard library (net/http routing, log/slog) plus the official InfluxDB 2 client. Fails closed at startup on a missing InfluxDB setting or an ingest token under 24 characters. - ABRP forwarder ported: newest fresh sample, rate limited, never queued, credentials only in the form body. - 22 tests: validation, aggregation, forwarding, config, and the handlers through a fake store. govulncheck clean (x/net 0.60.0, toolchain go1.26.9). - Image: static binary on distroless, about 11 MB, UID 65532, port 8080; the build runs vet and the tests. - Dev shell: Go, gopls and govulncheck instead of Node. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01QLJfZQZeAKAwSqViTmLzki
2026-10-17 15:17:42 +02:00
parent 538d03361d
commit 51e6f6fd48
82 changed files with 1673 additions and 3966 deletions
@@ -0,0 +1,185 @@
+package main
+
+import (
+	"errors"
+	"strings"
+	"testing"
+)
+
+const (
+	testInstallation = "6f1a2b3c-4d5e-4f60-8a9b-0c1d2e3f4a5b"
+	testSession      = "11111111-2222-4333-8444-555555555555"
+	testNowS         = 1_790_000_000
+)
+
+func isValidationError(err error) bool {
+	var v *ValidationError
+	return errors.As(err, &v)
+}
+
+func TestConsumptionAcceptsAWellFormedChunk(t *testing.T) {
+	c, err := validateConsumption([]byte(`{"installationId":"` + testInstallation + `","date":"2026-10-07",
+		"recordedAt":1760000000000,"day":{"km":42.5,"kwh":7.25,"hours":0.9,"socDrop":11.5},
+		"lifetime":{"km":12000,"kwh":2100,"hours":240,"socDrop":3400},"sohPercent":97.5}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if c.Date != "2026-10-07" || c.Day.Kwh != 7.25 || c.RecordedAt.UnixMilli() != 1760000000000 || *c.SohPercent != 97.5 {
+		t.Fatalf("unexpected chunk %+v", c)
+	}
+}
+
+func TestConsumptionMissingSohIsOmittedNotDefaulted(t *testing.T) {
+	// The car omits a field it could not read. Writing 0 would be a battery at nothing.
+	c, err := validateConsumption([]byte(`{"installationId":"` + testInstallation + `","date":"2026-10-07",
+		"recordedAt":1,"day":{"km":1,"kwh":1,"hours":1,"socDrop":1}}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if c.SohPercent != nil {
+		t.Fatalf("SoH should be absent, got %v", *c.SohPercent)
+	}
+}
+
+func TestConsumptionRejectsBadInput(t *testing.T) {
+	base := map[string]string{
+		"installationId": `"` + testInstallation + `"`, "date": `"2026-10-07"`, "recordedAt": "1",
+		"day": `{"km":1,"kwh":1,"hours":1,"socDrop":1}`,
+	}
+	cases := map[string][2]string{
+		"bad id":             {"installationId", `"nope"`},
+		"german date":        {"date", `"07.10.2026"`},
+		"negative timestamp": {"recordedAt", "-5"},
+		"fractional time":    {"recordedAt", "1.5"},
+		"string number":      {"day", `{"km":"1","kwh":1,"hours":1,"socDrop":1}`},
+		"huge totals":        {"day", `{"km":1e9,"kwh":1,"hours":1,"socDrop":1}`},
+		"missing field":      {"day", `{"km":1,"kwh":1,"hours":1}`},
+		"bad lifetime":       {"lifetime", `{"km":1}`},
+		"soh above 100":      {"sohPercent", "101"},
+	}
+	for name, change := range cases {
+		fields := map[string]string{}
+		for k, v := range base {
+			fields[k] = v
+		}
+		fields[change[0]] = change[1]
+		var parts []string
+		for k, v := range fields {
+			parts = append(parts, `"`+k+`":`+v)
+		}
+		if _, err := validateConsumption([]byte("{" + strings.Join(parts, ",") + "}")); !isValidationError(err) {
+			t.Errorf("%s: want ValidationError, got %v", name, err)
+		}
+	}
+	for _, body := range []string{"", "[]", "null", "{", `{"a":1}{"b":2}`} {
+		if _, err := validateConsumption([]byte(body)); !isValidationError(err) {
+			t.Errorf("body %q: want ValidationError, got %v", body, err)
+		}
+	}
+}
+
+func chargingBody(overrides string) []byte {
+	return []byte(`{"installationId":"` + testInstallation + `","sessionId":"` + testSession + `",
+		"startedAt":1760500000000,"endedAt":1760501800000,"durationSeconds":1800,"energyKwh":30,
+		"pricePerKwh":0.59,"startSocPercent":20,"endSocPercent":80,
+		"curve":[{"timestampMs":1760500060000,"powerKw":95,"socPercent":21},{"timestampMs":1760500120000,"powerKw":110}]` +
+		overrides + `}`)
+}
+
+func TestChargingSessionAppliesTheServersLossAndCost(t *testing.T) {
+	// The car's own grid and cost figures are not trusted; the server applies 10 % loss.
+	s, err := validateChargingSession(chargingBody(`,"gridEnergyKwh":1,"totalCost":1`), testSession)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if s.GridEnergyKwh != 33 || s.TotalCost != 33*0.59 || s.ChargingLossPercent != 10 {
+		t.Fatalf("grid %v cost %v loss %v", s.GridEnergyKwh, s.TotalCost, s.ChargingLossPercent)
+	}
+	if len(s.Curve) != 2 || s.Curve[1].SocPercent != nil || *s.Curve[0].SocPercent != 21 {
+		t.Fatalf("curve not kept as sent: %+v", s.Curve)
+	}
+}
+
+func TestChargingSessionMustMatchItsPath(t *testing.T) {
+	if _, err := validateChargingSession(chargingBody(""), "22222222-2222-4333-8444-555555555555"); !isValidationError(err) {
+		t.Fatalf("want ValidationError, got %v", err)
+	}
+}
+
+func TestChargingSessionRejectsOversizedCurvesAndBadPoints(t *testing.T) {
+	points := strings.Repeat(`{"timestampMs":1,"powerKw":1},`, 721)
+	long := []byte(`{"installationId":"` + testInstallation + `","sessionId":"` + testSession + `","curve":[` +
+		strings.TrimSuffix(points, ",") + `]}`)
+	if _, err := validateChargingSession(long, testSession); !isValidationError(err) {
+		t.Errorf("721 points: want ValidationError, got %v", err)
+	}
+	bad := []byte(strings.Replace(string(chargingBody("")), `"powerKw":95`, `"powerKw":-5`, 1))
+	if _, err := validateChargingSession(bad, testSession); !isValidationError(err) {
+		t.Errorf("negative power: want ValidationError, got %v", err)
+	}
+}
+
+func telemetryBody(samples string) []byte {
+	return []byte(`{"installationId":"` + testInstallation + `","samples":[` + samples + `]}`)
+}
+
+func TestTelemetryKeepsOnlyWhatWasSent(t *testing.T) {
+	b, err := validateTelemetryBatch(telemetryBody(
+		`{"utc":1790000000,"soc":81,"power":-12.5,"speed":0,"lat":52.1,"lon":7.6,"is_charging":1,"is_dcfc":false}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	s := b.Samples[0]
+	if s.UTC != testNowS || s.Numbers["soc"] != 81 || s.Numbers["power"] != -12.5 || s.Numbers["lat"] != 52.1 {
+		t.Fatalf("numbers %+v", s.Numbers)
+	}
+	if v, ok := s.Numbers["speed"]; !ok || v != 0 {
+		t.Fatal("a real 0 must be kept")
+	}
+	if s.Flags["is_charging"] != true || s.Flags["is_dcfc"] != false || len(s.Flags) != 2 {
+		t.Fatalf("flags %+v", s.Flags)
+	}
+	// An unread signal stays absent: a missing SOC must never become 0.
+	if _, ok := s.Numbers["est_battery_range"]; ok {
+		t.Fatal("absent field invented")
+	}
+}
+
+func TestTelemetryDropsUnknownFields(t *testing.T) {
+	b, err := validateTelemetryBatch(telemetryBody(`{"utc":1790000000,"future_field":3}`))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(b.Samples[0].Numbers) != 0 || len(b.Samples[0].Flags) != 0 {
+		t.Fatalf("unknown field kept: %+v", b.Samples[0])
+	}
+}
+
+func TestTelemetryRejectsBadSamples(t *testing.T) {
+	for name, sample := range map[string]string{
+		"milliseconds":   `{"utc":1790000000000}`,
+		"fractional utc": `{"utc":1790000000.5}`,
+		"soc above 100":  `{"utc":1790000000,"soc":101}`,
+		"string speed":   `{"utc":1790000000,"speed":"fast"}`,
+		"flag 2":         `{"utc":1790000000,"is_parked":2}`,
+		"half position":  `{"utc":1790000000,"lat":52.1}`,
+		"not an object":  `5`,
+	} {
+		if _, err := validateTelemetryBatch(telemetryBody(sample)); !isValidationError(err) {
+			t.Errorf("%s: want ValidationError, got %v", name, err)
+		}
+	}
+}
+
+func TestTelemetryRejectsEmptyAndOversizedBatches(t *testing.T) {
+	if _, err := validateTelemetryBatch(telemetryBody("")); !isValidationError(err) {
+		t.Error("empty batch accepted")
+	}
+	many := strings.TrimSuffix(strings.Repeat(`{"utc":1790000000},`, 501), ",")
+	if _, err := validateTelemetryBatch(telemetryBody(many)); !isValidationError(err) {
+		t.Error("501 samples accepted")
+	}
+	if _, err := validateTelemetryBatch([]byte(`{"installationId":"nope","samples":[{"utc":1790000000}]}`)); !isValidationError(err) {
+		t.Error("bad installation id accepted")
+	}
+}