.github/workflows/pr-check.yml

@@ -5,14 +5,20 @@ on:
     branches: [main]
 
 jobs:
-  test:
+  build:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
 
-      - uses: actions/setup-go@v5
+      - name: Set up QEMU
-        with:
+        uses: docker/setup-qemu-action@v3
-          go-version-file: go.mod
 
-      - name: Test
+      - name: Set up Docker Buildx
-        run: go test -race ./...
+        uses: docker/setup-buildx-action@v3
+
+      - name: Build
+        uses: docker/build-push-action@v6
+        with:
+          context: .
+          push: false
+          platforms: linux/amd64,linux/arm64

Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.24-alpine AS builder
+FROM golang:1.22-alpine AS builder
 WORKDIR /src
 COPY go.mod go.sum ./
 RUN go mod download

README.md

@@ -63,20 +63,6 @@ docker run -d \
   rwejlgaard/octopus_exporter
 ```
 
-## Docker Compose
-
-```yaml
-services:
-  octopus-exporter:
-    image: rwejlgaard/octopus_exporter:latest
-    restart: unless-stopped
-    environment:
-      OCTOPUS_API_KEY: sk_live_...
-      OCTOPUS_MPAN: "1234567890123"   # optional, auto-discovered if omitted
-    ports:
-      - "9359:9359"
-```
-
 ## Running from source
 
 Requires Go 1.22+.

cmd/octopus_exporter/agile.go

@@ -9,7 +9,7 @@ import (
 
 // getCurrentAgileRate returns the unit rate (inc. VAT, pence/kWh) for the current
 // half-hour slot from the Agile tariff REST endpoint.
-func getCurrentAgileRate(productCode, tariffCode, key string) (float64, error) {
+func getCurrentAgileRate(productCode, tariffCode string) (float64, error) {
 	now := time.Now().UTC()
 	slotStart := now.Truncate(30 * time.Minute)
 	slotEnd := slotStart.Add(30 * time.Minute)
@@ -18,7 +18,7 @@ func getCurrentAgileRate(productCode, tariffCode, key string) (float64, error) {
 	result, err := doREST(path, url.Values{
 		"period_from": {slotStart.Format(time.RFC3339)},
 		"period_to":   {slotEnd.Format(time.RFC3339)},
-	}, key)
+	})
 	if err != nil {
 		return 0, err
 	}

cmd/octopus_exporter/agile_test.go

@@ -15,8 +15,9 @@ func TestGetCurrentAgileRate_Success(t *testing.T) {
 	}))
 	defer srv.Close()
 	octopusREST = srv.URL
+	apiKey = "test"
 
-	rate, err := getCurrentAgileRate("AGILE-24-10-01", "E-1R-AGILE-24-10-01-C", "test")
+	rate, err := getCurrentAgileRate("AGILE-24-10-01", "E-1R-AGILE-24-10-01-C")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -31,8 +32,9 @@ func TestGetCurrentAgileRate_NoSlot(t *testing.T) {
 	}))
 	defer srv.Close()
 	octopusREST = srv.URL
+	apiKey = "test"
 
-	_, err := getCurrentAgileRate("AGILE-24-10-01", "E-1R-AGILE-24-10-01-C", "test")
+	_, err := getCurrentAgileRate("AGILE-24-10-01", "E-1R-AGILE-24-10-01-C")
 	if err == nil {
 		t.Error("expected error for empty slot, got nil")
 	}
@@ -46,8 +48,9 @@ func TestGetCurrentAgileRate_CorrectPath(t *testing.T) {
 	}))
 	defer srv.Close()
 	octopusREST = srv.URL
+	apiKey = "test"
 
-	getCurrentAgileRate("AGILE-24-10-01", "E-1R-AGILE-24-10-01-C", "test")
+	getCurrentAgileRate("AGILE-24-10-01", "E-1R-AGILE-24-10-01-C")
 
 	want := "/v1/products/AGILE-24-10-01/electricity-tariffs/E-1R-AGILE-24-10-01-C/standard-unit-rates/"
 	if capturedPath != want {

cmd/octopus_exporter/client.go

@@ -6,20 +6,11 @@ import (
 	"errors"
 	"fmt"
 	"io"
-	"log"
 	"net/http"
 	"strconv"
-	"strings"
-	"time"
-
-	"github.com/prometheus/client_golang/prometheus"
 )
 
-var (
+var octopusGraphQL = "https://api.octopus.energy/v1/graphql/"
-	octopusGraphQL   = "https://api.octopus.energy/v1/graphql/"
-	httpClient       = &http.Client{Timeout: 15 * time.Second}
-	rateLimitRetries prometheus.Counter
-)
 
 type gqlRequest struct {
 	OperationName string         `json:"operationName,omitempty"`
@@ -48,72 +39,25 @@ func (f *jsonFloat) UnmarshalJSON(data []byte) error {
 	return nil
 }
 
-// executeWithRetry executes an HTTP request, retrying on 429 with exponential
-// backoff (honouring Retry-After when present). Returns the raw response body.
-func executeWithRetry(makeReq func() (*http.Request, error)) ([]byte, error) {
-	const maxRetries = 5
-	backoff := 30 * time.Second
-	for attempt := 0; attempt <= maxRetries; attempt++ {
-		req, err := makeReq()
-		if err != nil {
-			return nil, err
-		}
-		resp, err := httpClient.Do(req)
-		if err != nil {
-			return nil, err
-		}
-		if resp.StatusCode == http.StatusTooManyRequests {
-			resp.Body.Close()
-			if attempt == maxRetries {
-				return nil, errors.New("rate limited: max retries exceeded")
-			}
-			if rateLimitRetries != nil {
-				rateLimitRetries.Inc()
-			}
-			wait := backoff
-			if ra := resp.Header.Get("Retry-After"); ra != "" {
-				if secs, err := strconv.Atoi(ra); err == nil {
-					wait = time.Duration(secs) * time.Second
-				}
-			}
-			log.Printf("rate limited; retrying in %v (attempt %d/%d)", wait, attempt+1, maxRetries)
-			time.Sleep(wait)
-			backoff *= 2
-			continue
-		}
-		raw, err := io.ReadAll(resp.Body)
-		resp.Body.Close()
-		if err != nil {
-			return nil, err
-		}
-		if resp.StatusCode < 200 || resp.StatusCode >= 300 {
-			snippet := strings.TrimSpace(string(raw))
-			if len(snippet) > 200 {
-				snippet = snippet[:200]
-			}
-			return nil, fmt.Errorf("HTTP %d: %s", resp.StatusCode, snippet)
-		}
-		return raw, nil
-	}
-	return nil, errors.New("rate limited: max retries exceeded")
-}
-
 func doGraphQL(req gqlRequest, authToken string) (map[string]any, error) {
 	body, err := json.Marshal(req)
 	if err != nil {
 		return nil, err
 	}
-	raw, err := executeWithRetry(func() (*http.Request, error) {
+	httpReq, err := http.NewRequest(http.MethodPost, octopusGraphQL, bytes.NewReader(body))
-		httpReq, err := http.NewRequest(http.MethodPost, octopusGraphQL, bytes.NewReader(body))
+	if err != nil {
-		if err != nil {
+		return nil, err
-			return nil, err
+	}
-		}
+	httpReq.Header.Set("Content-Type", "application/json")
-		httpReq.Header.Set("Content-Type", "application/json")
+	if authToken != "" {
-		if authToken != "" {
+		httpReq.Header.Set("Authorization", "JWT "+authToken)
-			httpReq.Header.Set("Authorization", "JWT "+authToken)
+	}
-		}
+	resp, err := http.DefaultClient.Do(httpReq)
-		return httpReq, nil
+	if err != nil {
-	})
+		return nil, err
+	}
+	defer resp.Body.Close()
+	raw, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return nil, err
 	}
@@ -123,11 +67,7 @@ func doGraphQL(req gqlRequest, authToken string) (map[string]any, error) {
 	}
 	if errs, ok := result["errors"].([]any); ok && len(errs) > 0 {
 		if e, ok := errs[0].(map[string]any); ok {
-			msg, _ := e["message"].(string)
+			return nil, fmt.Errorf("GraphQL error: %s", e["message"])
-			if strings.Contains(msg, "JWT") && strings.Contains(msg, "expired") {
-				return nil, errTokenExpired
-			}
-			return nil, fmt.Errorf("GraphQL error: %s", msg)
 		}
 		return nil, errors.New("GraphQL error")
 	}

cmd/octopus_exporter/client_test.go

@@ -2,11 +2,6 @@ package main
 
 import (
 	"encoding/json"
-	"fmt"
-	"net/http"
-	"net/http/httptest"
-	"strings"
-	"sync/atomic"
 	"testing"
 )
 
@@ -56,66 +51,3 @@ func TestToSlice_WrongType(t *testing.T) {
 		t.Errorf("expected nil for wrong type, got %v", got)
 	}
 }
-
-func TestExecuteWithRetry_RateLimitRetry(t *testing.T) {
-	var attempts atomic.Int32
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		n := attempts.Add(1)
-		if n < 3 {
-			w.Header().Set("Retry-After", "0")
-			w.WriteHeader(http.StatusTooManyRequests)
-			return
-		}
-		fmt.Fprint(w, `ok`)
-	}))
-	defer srv.Close()
-
-	raw, err := executeWithRetry(func() (*http.Request, error) {
-		return http.NewRequest(http.MethodGet, srv.URL, nil)
-	})
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if string(raw) != "ok" {
-		t.Errorf("got body %q, want %q", string(raw), "ok")
-	}
-	if attempts.Load() != 3 {
-		t.Errorf("got %d attempts, want 3", attempts.Load())
-	}
-}
-
-func TestExecuteWithRetry_Non200Error(t *testing.T) {
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		w.WriteHeader(http.StatusUnauthorized)
-		fmt.Fprint(w, `{"error":"unauthorized"}`)
-	}))
-	defer srv.Close()
-
-	_, err := executeWithRetry(func() (*http.Request, error) {
-		return http.NewRequest(http.MethodGet, srv.URL, nil)
-	})
-	if err == nil {
-		t.Error("expected error for 401, got nil")
-	}
-	if !strings.Contains(err.Error(), "401") {
-		t.Errorf("expected error to contain status code, got: %v", err)
-	}
-}
-
-func TestExecuteWithRetry_ServerError(t *testing.T) {
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		w.WriteHeader(http.StatusInternalServerError)
-		fmt.Fprint(w, `internal server error`)
-	}))
-	defer srv.Close()
-
-	_, err := executeWithRetry(func() (*http.Request, error) {
-		return http.NewRequest(http.MethodGet, srv.URL, nil)
-	})
-	if err == nil {
-		t.Error("expected error for 500, got nil")
-	}
-	if !strings.Contains(err.Error(), "500") {
-		t.Errorf("expected error to contain status code, got: %v", err)
-	}
-}

cmd/octopus_exporter/consumption.go

@@ -12,7 +12,7 @@ type consumptionReading struct {
 	IntervalStart time.Time
 }
 
-func getLatestConsumption(kind meterKind, id, serial, key string) (*consumptionReading, error) {
+func getLatestConsumption(kind meterKind, id, serial string) (*consumptionReading, error) {
 	var path string
 	switch kind {
 	case electricity:
@@ -25,7 +25,7 @@ func getLatestConsumption(kind meterKind, id, serial, key string) (*consumptionR
 	result, err := doREST(path, url.Values{
 		"period_from": {time.Now().UTC().Add(-24 * time.Hour).Format(time.RFC3339)},
 		"order_by":    {"period"},
-	}, key)
+	})
 	if err != nil {
 		return nil, err
 	}
@@ -35,16 +35,9 @@ func getLatestConsumption(kind meterKind, id, serial, key string) (*consumptionR
 		return nil, errors.New("no consumption data in last 24h")
 	}
 
-	latest, ok := results[len(results)-1].(map[string]any)
+	latest := results[len(results)-1].(map[string]any)
-	if !ok {
-		return nil, errors.New("unexpected API response: invalid result entry")
-	}
 	kwh, _ := latest["consumption"].(float64)
-	startStr, ok := latest["interval_start"].(string)
+	start, err := time.Parse(time.RFC3339, latest["interval_start"].(string))
-	if !ok {
-		return nil, errors.New("unexpected API response: missing interval_start")
-	}
-	start, err := time.Parse(time.RFC3339, startStr)
 	if err != nil {
 		return nil, fmt.Errorf("failed to parse interval_start: %w", err)
 	}

cmd/octopus_exporter/consumption_test.go

@@ -16,8 +16,9 @@ func TestGetLatestConsumption_ReturnsLatestInterval(t *testing.T) {
 	}))
 	defer srv.Close()
 	octopusREST = srv.URL
+	apiKey = "test"
 
-	c, err := getLatestConsumption(electricity, "MPAN123", "SERIAL456", "test")
+	c, err := getLatestConsumption(electricity, "MPAN123", "SERIAL456")
 	if err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
@@ -32,8 +33,9 @@ func TestGetLatestConsumption_Empty(t *testing.T) {
 	}))
 	defer srv.Close()
 	octopusREST = srv.URL
+	apiKey = "test"
 
-	_, err := getLatestConsumption(electricity, "MPAN123", "SERIAL456", "test")
+	_, err := getLatestConsumption(electricity, "MPAN123", "SERIAL456")
 	if err == nil {
 		t.Error("expected error for empty results, got nil")
 	}
@@ -49,25 +51,12 @@ func TestGetLatestConsumption_GasPath(t *testing.T) {
 	}))
 	defer srv.Close()
 	octopusREST = srv.URL
+	apiKey = "test"
 
-	getLatestConsumption(gas, "MPRN789", "SERIAL456", "test")
+	getLatestConsumption(gas, "MPRN789", "SERIAL456")
 
 	want := "/v1/gas-meter-points/MPRN789/meters/SERIAL456/consumption/"
 	if capturedPath != want {
 		t.Errorf("got path %q, want %q", capturedPath, want)
 	}
 }
-
-func TestGetLatestConsumption_Non200Error(t *testing.T) {
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		w.WriteHeader(http.StatusUnauthorized)
-		fmt.Fprint(w, `{"error":"unauthorized"}`)
-	}))
-	defer srv.Close()
-	octopusREST = srv.URL
-
-	_, err := getLatestConsumption(electricity, "MPAN123", "SERIAL456", "bad-key")
-	if err == nil {
-		t.Error("expected error for 401, got nil")
-	}
-}

cmd/octopus_exporter/main.go

@@ -1,12 +1,9 @@
 package main
 
 import (
-	"errors"
 	"log"
 	"net/http"
 	"os"
-	"sync"
-	"sync/atomic"
 	"time"
 
 	"github.com/prometheus/client_golang/prometheus"
@@ -37,10 +34,6 @@ func gauge(name, help string) prometheus.Gauge {
 	return prometheus.NewGauge(prometheus.GaugeOpts{Name: name, Help: help})
 }
 
-func counter(name, help string) prometheus.Counter {
-	return prometheus.NewCounter(prometheus.CounterOpts{Name: name, Help: help})
-}
-
 func main() {
 	apiKey = mustEnv("OCTOPUS_API_KEY")
 	port = envOrDefault("PORT", "9359")
@@ -50,13 +43,7 @@ func main() {
 		log.Fatalf("failed to get initial token: %v", err)
 	}
 
-	log.Println("discovering meters from account...")
+	elecMeter, err := resolveMeter(token, electricity)
-	candidates, err := getMeters(token)
-	if err != nil {
-		log.Fatalf("failed to discover meters: %v", err)
-	}
-
-	elecMeter, err := resolveMeter(candidates, electricity)
 	if err != nil {
 		log.Fatalf("failed to resolve electricity meter: %v", err)
 	}
@@ -64,7 +51,7 @@ func main() {
 		log.Fatal("no electricity smart meter found on account")
 	}
 
-	gasMeter, err := resolveMeter(candidates, gas)
+	gasMeter, err := resolveMeter(token, gas)
 	if err != nil {
 		log.Fatalf("failed to resolve gas meter: %v", err)
 	}
@@ -89,27 +76,20 @@ func main() {
 	// Account
 	accountBalance := gauge("octopus_account_balance_pence", "Account balance in pence (positive = credit, negative = debit)")
 
-	// Exporter health
-	exporterUp := gauge("octopus_up", "1 if the last poll cycle completed without errors, 0 otherwise")
-	pollErrors := counter("octopus_poll_errors_total", "Total number of collector errors per poll cycle")
-	tokenRefreshCount := counter("octopus_token_refreshes_total", "Total number of successful JWT token refreshes")
-	rateLimitRetries = counter("octopus_rate_limit_retries_total", "Total number of 429 rate-limit retries across all requests")
-
 	toRegister := []prometheus.Collector{
 		elecDemand, elecLastRead,
 		elecConsumption, elecConsumptionInterval,
 		elecUnitRate, elecStandingCharge,
 		accountBalance,
-		exporterUp, pollErrors, tokenRefreshCount, rateLimitRetries,
 	}
 
 	var (
-		gasDemand              prometheus.Gauge
+		gasDemand            prometheus.Gauge
-		gasLastRead            prometheus.Gauge
+		gasLastRead          prometheus.Gauge
-		gasConsumption         prometheus.Gauge
+		gasConsumption       prometheus.Gauge
 		gasConsumptionInterval prometheus.Gauge
-		gasUnitRate            prometheus.Gauge
+		gasUnitRate          prometheus.Gauge
-		gasStandCharge         prometheus.Gauge
+		gasStandCharge       prometheus.Gauge
 	)
 	if gasMeter != nil {
 		gasDemand = gauge("octopus_gas_demand_watts", "Live gas demand in watts")
@@ -131,170 +111,87 @@ func main() {
 		}
 	}()
 
-	// tokenMu guards token across concurrent poll goroutines.
-	var tokenMu sync.RWMutex
-
-	// withToken calls fn with the current token, refreshing once on JWT expiry.
-	withToken := func(fn func(string) error) error {
-		tokenMu.RLock()
-		t := token
-		tokenMu.RUnlock()
-
-		err := fn(t)
-		if !errors.Is(err, errTokenExpired) {
-			return err
-		}
-
-		// Only one goroutine refreshes; others will pick up the new token.
-		tokenMu.Lock()
-		if token == t {
-			newT, e := getKrakenToken(apiKey)
-			if e != nil {
-				tokenMu.Unlock()
-				log.Printf("token refresh failed: %v", e)
-				return err
-			}
-			token = newT
-			tokenRefreshCount.Inc()
-		}
-		newT := token
-		tokenMu.Unlock()
-
-		return fn(newT)
-	}
-
 	for {
-		var (
-			wg        sync.WaitGroup
-			failedAny atomic.Bool
-		)
-
-		fail := func(format string, args ...any) {
-			log.Printf(format, args...)
-			pollErrors.Inc()
-			failedAny.Store(true)
-		}
-
-		collect := func(name string, fn func() error) {
-			wg.Add(1)
-			go func() {
-				defer wg.Done()
-				if err := fn(); err != nil {
-					fail("%s error: %v", name, err)
-				}
-			}()
-		}
-
 		// Electricity telemetry (live demand)
 		if elecMeter.deviceID != "" {
-			collect("electricity telemetry", func() error {
+			reading, err := getLiveConsumption(token, elecMeter.deviceID)
-				return withToken(func(t string) error {
+			if err != nil {
-					reading, err := getLiveConsumption(t, elecMeter.deviceID)
+				log.Printf("electricity telemetry error: %v", err)
-					if err != nil {
+				if token, err = getKrakenToken(apiKey); err != nil {
-						return err
+					log.Printf("token refresh failed: %v", err)
-					}
+				}
-					elecDemand.Set(float64(reading.Demand))
+			} else {
-					if ts, err := time.Parse(time.RFC3339, reading.ReadAt); err == nil {
+				elecDemand.Set(float64(reading.Demand))
-						elecLastRead.Set(float64(ts.Unix()))
+				if t, err := time.Parse("2006-01-02T15:04:05+00:00", reading.ReadAt); err == nil {
-					}
+					elecLastRead.Set(float64(t.Unix()))
-					return nil
+				}
-				})
+			}
-			})
 		}
 
 		// Gas telemetry (live demand)
 		if gasMeter != nil && gasMeter.deviceID != "" {
-			collect("gas telemetry", func() error {
+			reading, err := getLiveConsumption(token, gasMeter.deviceID)
-				return withToken(func(t string) error {
+			if err != nil {
-					reading, err := getLiveConsumption(t, gasMeter.deviceID)
+				log.Printf("gas telemetry error: %v", err)
-					if err != nil {
+			} else {
-						return err
+				gasDemand.Set(float64(reading.Demand))
-					}
+				if t, err := time.Parse("2006-01-02T15:04:05+00:00", reading.ReadAt); err == nil {
-					gasDemand.Set(float64(reading.Demand))
+					gasLastRead.Set(float64(t.Unix()))
-					if ts, err := time.Parse(time.RFC3339, reading.ReadAt); err == nil {
+				}
-						gasLastRead.Set(float64(ts.Unix()))
+			}
-					}
-					return nil
-				})
-			})
 		}
 
 		// Electricity half-hourly consumption (REST)
 		if elecMeter.mpan != "" && elecMeter.serial != "" {
-			collect("electricity consumption", func() error {
+			c, err := getLatestConsumption(electricity, elecMeter.mpan, elecMeter.serial)
-				c, err := getLatestConsumption(electricity, elecMeter.mpan, elecMeter.serial, apiKey)
+			if err != nil {
-				if err != nil {
+				log.Printf("electricity consumption error: %v", err)
-					return err
+			} else {
-				}
 				elecConsumption.Set(c.KWh)
 				elecConsumptionInterval.Set(float64(c.IntervalStart.Unix()))
-				return nil
+			}
-			})
 		}
 
 		// Gas half-hourly consumption (REST)
 		if gasMeter != nil && gasMeter.mprn != "" && gasMeter.serial != "" {
-			collect("gas consumption", func() error {
+			c, err := getLatestConsumption(gas, gasMeter.mprn, gasMeter.serial)
-				c, err := getLatestConsumption(gas, gasMeter.mprn, gasMeter.serial, apiKey)
+			if err != nil {
-				if err != nil {
+				log.Printf("gas consumption error: %v", err)
-					return err
+			} else {
-				}
 				gasConsumption.Set(c.KWh)
 				gasConsumptionInterval.Set(float64(c.IntervalStart.Unix()))
-				return nil
+			}
-			})
 		}
 
-		// Tariff rates (result needed for optional agile lookup after wg.Wait)
+		// Tariff rates
-		var collectedRates *tariffRates
+		rates, err := getRates(token)
-		collect("rates", func() error {
+		if err != nil {
-			return withToken(func(t string) error {
+			log.Printf("rates error: %v", err)
-				r, err := getRates(t)
+		} else {
+			unitRate := rates.ElectricityUnitRate
+			if rates.ElectricityIsAgile && rates.ElectricityProductCode != "" && rates.ElectricityTariffCode != "" {
+				agileRate, err := getCurrentAgileRate(rates.ElectricityProductCode, rates.ElectricityTariffCode)
 				if err != nil {
-					return err
+					log.Printf("agile rate error: %v", err)
-				}
-				collectedRates = r
-				return nil
-			})
-		})
-
-		// Account balance
-		collect("account balance", func() error {
-			return withToken(func(t string) error {
-				balance, err := getAccountBalance(t)
-				if err != nil {
-					return err
-				}
-				accountBalance.Set(balance)
-				return nil
-			})
-		})
-
-		wg.Wait()
-
-		// Agile rate depends on the rates result, so it runs after the parallel phase.
-		if collectedRates != nil {
-			unitRate := collectedRates.ElectricityUnitRate
-			if collectedRates.ElectricityIsAgile && collectedRates.ElectricityProductCode != "" && collectedRates.ElectricityTariffCode != "" {
-				agileRate, err := getCurrentAgileRate(collectedRates.ElectricityProductCode, collectedRates.ElectricityTariffCode, apiKey)
-				if err != nil {
-					fail("agile rate error: %v", err)
 				} else {
 					unitRate = agileRate
 				}
 			}
 			elecUnitRate.Set(unitRate)
-			elecStandingCharge.Set(collectedRates.ElectricityStandingCharge)
+			elecStandingCharge.Set(rates.ElectricityStandingCharge)
+
 			if gasMeter != nil {
-				gasUnitRate.Set(collectedRates.GasUnitRate)
+				gasUnitRate.Set(rates.GasUnitRate)
-				gasStandCharge.Set(collectedRates.GasStandingCharge)
+				gasStandCharge.Set(rates.GasStandingCharge)
 			}
 		}
 
-		if failedAny.Load() {
+		// Account balance
-			exporterUp.Set(0)
+		balance, err := getAccountBalance(token)
+		if err != nil {
+			log.Printf("account balance error: %v", err)
 		} else {
-			exporterUp.Set(1)
+			accountBalance.Set(balance)
 		}
 
 		time.Sleep(60 * time.Second)

cmd/octopus_exporter/meters.go

@@ -53,71 +53,40 @@ func getMeters(token string) ([]meterCandidate, error) {
 
 	var candidates []meterCandidate
 
-	data, _ := result["data"].(map[string]any)
+	accounts, _ := result["data"].(map[string]any)["viewer"].(map[string]any)["accounts"].([]any)
-	viewer, _ := data["viewer"].(map[string]any)
-	accounts, _ := viewer["accounts"].([]any)
 	for _, a := range accounts {
 		props, _ := a.(map[string]any)["properties"].([]any)
 		for _, p := range props {
-			pm, ok := p.(map[string]any)
+			pm := p.(map[string]any)
-			if !ok {
-				continue
-			}
 
 			for _, mp := range toSlice(pm["electricityMeterPoints"]) {
-				mpPoint, ok := mp.(map[string]any)
+				mpan, _ := mp.(map[string]any)["mpan"].(string)
-				if !ok {
+				for _, m := range toSlice(mp.(map[string]any)["meters"]) {
-					continue
+					serial, _ := m.(map[string]any)["serialNumber"].(string)
-				}
+					for _, d := range toSlice(m.(map[string]any)["smartDevices"]) {
-				mpan, _ := mpPoint["mpan"].(string)
+						deviceID, _ := d.(map[string]any)["deviceId"].(string)
-				for _, m := range toSlice(mpPoint["meters"]) {
-					meterMap, ok := m.(map[string]any)
-					if !ok {
-						continue
-					}
-					serial, _ := meterMap["serialNumber"].(string)
-					devices := toSlice(meterMap["smartDevices"])
-					for _, d := range devices {
-						dMap, ok := d.(map[string]any)
-						if !ok {
-							continue
-						}
-						deviceID, _ := dMap["deviceId"].(string)
 						if deviceID != "" {
 							candidates = append(candidates, meterCandidate{kind: electricity, mpan: mpan, serial: serial, deviceID: deviceID})
 						}
 					}
 					// Include meters without smart devices so we can still use the REST consumption endpoint.
-					if len(devices) == 0 && serial != "" {
+					if len(toSlice(m.(map[string]any)["smartDevices"])) == 0 && serial != "" {
 						candidates = append(candidates, meterCandidate{kind: electricity, mpan: mpan, serial: serial})
 					}
 				}
 			}
 
 			for _, mp := range toSlice(pm["gasMeterPoints"]) {
-				mpPoint, ok := mp.(map[string]any)
+				mprn, _ := mp.(map[string]any)["mprn"].(string)
-				if !ok {
+				for _, m := range toSlice(mp.(map[string]any)["meters"]) {
-					continue
+					serial, _ := m.(map[string]any)["serialNumber"].(string)
-				}
+					for _, d := range toSlice(m.(map[string]any)["smartDevices"]) {
-				mprn, _ := mpPoint["mprn"].(string)
+						deviceID, _ := d.(map[string]any)["deviceId"].(string)
-				for _, m := range toSlice(mpPoint["meters"]) {
-					meterMap, ok := m.(map[string]any)
-					if !ok {
-						continue
-					}
-					serial, _ := meterMap["serialNumber"].(string)
-					devices := toSlice(meterMap["smartDevices"])
-					for _, d := range devices {
-						dMap, ok := d.(map[string]any)
-						if !ok {
-							continue
-						}
-						deviceID, _ := dMap["deviceId"].(string)
 						if deviceID != "" {
 							candidates = append(candidates, meterCandidate{kind: gas, mprn: mprn, serial: serial, deviceID: deviceID})
 						}
 					}
-					if len(devices) == 0 && serial != "" {
+					if len(toSlice(m.(map[string]any)["smartDevices"])) == 0 && serial != "" {
 						candidates = append(candidates, meterCandidate{kind: gas, mprn: mprn, serial: serial})
 					}
 				}
@@ -130,7 +99,7 @@ func getMeters(token string) ([]meterCandidate, error) {
 
 // resolveMeter finds the meter matching the env var filters for the given kind.
 // Returns (nil, nil) if no meter of that kind exists on the account.
-func resolveMeter(candidates []meterCandidate, kind meterKind) (*resolvedMeter, error) {
+func resolveMeter(token string, kind meterKind) (*resolvedMeter, error) {
 	var wantDeviceID, wantID, wantSerial string
 	switch kind {
 	case electricity:
@@ -143,6 +112,12 @@ func resolveMeter(candidates []meterCandidate, kind meterKind) (*resolvedMeter,
 		wantSerial = os.Getenv("OCTOPUS_GAS_SERIAL")
 	}
 
+	log.Printf("discovering %s meters from account...", kind)
+	candidates, err := getMeters(token)
+	if err != nil {
+		return nil, err
+	}
+
 	for _, c := range candidates {
 		if c.kind != kind {
 			continue

cmd/octopus_exporter/meters_test.go

@@ -1,209 +0,0 @@
-package main
-
-import (
-	"fmt"
-	"net/http"
-	"net/http/httptest"
-	"testing"
-)
-
-func TestResolveMeter_NoFilters_ReturnsFirst(t *testing.T) {
-	t.Setenv("OCTOPUS_DEVICE_ID", "")
-	t.Setenv("OCTOPUS_MPAN", "")
-	t.Setenv("OCTOPUS_SERIAL", "")
-
-	candidates := []meterCandidate{
-		{kind: electricity, mpan: "1000000000001", serial: "A001", deviceID: "dev1"},
-		{kind: electricity, mpan: "1000000000002", serial: "A002", deviceID: "dev2"},
-	}
-	m, err := resolveMeter(candidates, electricity)
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if m == nil {
-		t.Fatal("expected meter, got nil")
-	}
-	if m.mpan != "1000000000001" {
-		t.Errorf("got mpan %q, want 1000000000001", m.mpan)
-	}
-}
-
-func TestResolveMeter_FilterByMPAN(t *testing.T) {
-	t.Setenv("OCTOPUS_DEVICE_ID", "")
-	t.Setenv("OCTOPUS_MPAN", "1000000000002")
-	t.Setenv("OCTOPUS_SERIAL", "")
-
-	candidates := []meterCandidate{
-		{kind: electricity, mpan: "1000000000001", serial: "A001", deviceID: "dev1"},
-		{kind: electricity, mpan: "1000000000002", serial: "A002", deviceID: "dev2"},
-	}
-	m, err := resolveMeter(candidates, electricity)
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if m == nil {
-		t.Fatal("expected meter, got nil")
-	}
-	if m.mpan != "1000000000002" {
-		t.Errorf("got mpan %q, want 1000000000002", m.mpan)
-	}
-}
-
-func TestResolveMeter_FilterByDeviceID(t *testing.T) {
-	t.Setenv("OCTOPUS_DEVICE_ID", "dev2")
-	t.Setenv("OCTOPUS_MPAN", "")
-	t.Setenv("OCTOPUS_SERIAL", "")
-
-	candidates := []meterCandidate{
-		{kind: electricity, mpan: "1000000000001", serial: "A001", deviceID: "dev1"},
-		{kind: electricity, mpan: "1000000000002", serial: "A002", deviceID: "dev2"},
-	}
-	m, err := resolveMeter(candidates, electricity)
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if m.deviceID != "dev2" {
-		t.Errorf("got deviceID %q, want dev2", m.deviceID)
-	}
-}
-
-func TestResolveMeter_FilterMismatch_ReturnsError(t *testing.T) {
-	t.Setenv("OCTOPUS_MPAN", "9999999999999")
-	t.Setenv("OCTOPUS_DEVICE_ID", "")
-	t.Setenv("OCTOPUS_SERIAL", "")
-
-	candidates := []meterCandidate{
-		{kind: electricity, mpan: "1000000000001", serial: "A001"},
-	}
-	_, err := resolveMeter(candidates, electricity)
-	if err == nil {
-		t.Error("expected error for unmatched filter, got nil")
-	}
-}
-
-func TestResolveMeter_NoMetersOfKind_ReturnsNil(t *testing.T) {
-	t.Setenv("OCTOPUS_DEVICE_ID", "")
-	t.Setenv("OCTOPUS_MPAN", "")
-	t.Setenv("OCTOPUS_SERIAL", "")
-
-	candidates := []meterCandidate{
-		{kind: gas, mprn: "1111111111", serial: "G001"},
-	}
-	m, err := resolveMeter(candidates, electricity)
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if m != nil {
-		t.Errorf("expected nil for no electricity meters, got %+v", m)
-	}
-}
-
-func TestResolveMeter_GasFilterByMPRN(t *testing.T) {
-	t.Setenv("OCTOPUS_GAS_DEVICE_ID", "")
-	t.Setenv("OCTOPUS_GAS_MPRN", "2222222222")
-	t.Setenv("OCTOPUS_GAS_SERIAL", "")
-
-	candidates := []meterCandidate{
-		{kind: gas, mprn: "1111111111", serial: "G001"},
-		{kind: gas, mprn: "2222222222", serial: "G002"},
-	}
-	m, err := resolveMeter(candidates, gas)
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if m.mprn != "2222222222" {
-		t.Errorf("got mprn %q, want 2222222222", m.mprn)
-	}
-}
-
-func TestGetMeters_ElectricityWithSmartDevice(t *testing.T) {
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		fmt.Fprint(w, `{"data":{"viewer":{"accounts":[{"properties":[{
-			"electricityMeterPoints":[{
-				"mpan":"1000000000001",
-				"meters":[{"serialNumber":"A001","smartDevices":[{"deviceId":"dev1"}]}]
-			}],
-			"gasMeterPoints":[]
-		}]}]}}}`)
-	}))
-	defer srv.Close()
-	octopusGraphQL = srv.URL + "/"
-
-	candidates, err := getMeters("token")
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if len(candidates) != 1 {
-		t.Fatalf("got %d candidates, want 1", len(candidates))
-	}
-	c := candidates[0]
-	if c.kind != electricity {
-		t.Errorf("kind: got %q, want electricity", c.kind)
-	}
-	if c.mpan != "1000000000001" {
-		t.Errorf("mpan: got %q, want 1000000000001", c.mpan)
-	}
-	if c.deviceID != "dev1" {
-		t.Errorf("deviceID: got %q, want dev1", c.deviceID)
-	}
-}
-
-func TestGetMeters_MeterWithoutSmartDevice(t *testing.T) {
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		fmt.Fprint(w, `{"data":{"viewer":{"accounts":[{"properties":[{
-			"electricityMeterPoints":[{
-				"mpan":"1000000000001",
-				"meters":[{"serialNumber":"A001","smartDevices":[]}]
-			}],
-			"gasMeterPoints":[]
-		}]}]}}}`)
-	}))
-	defer srv.Close()
-	octopusGraphQL = srv.URL + "/"
-
-	candidates, err := getMeters("token")
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if len(candidates) != 1 {
-		t.Fatalf("got %d candidates, want 1", len(candidates))
-	}
-	if candidates[0].deviceID != "" {
-		t.Errorf("expected empty deviceID for meter without smart device, got %q", candidates[0].deviceID)
-	}
-}
-
-func TestGetMeters_BothElectricityAndGas(t *testing.T) {
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		fmt.Fprint(w, `{"data":{"viewer":{"accounts":[{"properties":[{
-			"electricityMeterPoints":[{
-				"mpan":"1000000000001",
-				"meters":[{"serialNumber":"A001","smartDevices":[{"deviceId":"dev1"}]}]
-			}],
-			"gasMeterPoints":[{
-				"mprn":"1111111111",
-				"meters":[{"serialNumber":"G001","smartDevices":[{"deviceId":"gdev1"}]}]
-			}]
-		}]}]}}}`)
-	}))
-	defer srv.Close()
-	octopusGraphQL = srv.URL + "/"
-
-	candidates, err := getMeters("token")
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if len(candidates) != 2 {
-		t.Fatalf("got %d candidates, want 2", len(candidates))
-	}
-	kinds := map[meterKind]bool{}
-	for _, c := range candidates {
-		kinds[c.kind] = true
-	}
-	if !kinds[electricity] {
-		t.Error("expected electricity candidate")
-	}
-	if !kinds[gas] {
-		t.Error("expected gas candidate")
-	}
-}

cmd/octopus_exporter/rates.go

@@ -31,16 +31,11 @@ func getRates(token string) (*tariffRates, error) {
 
 	rates := &tariffRates{}
 
-	data, _ := result["data"].(map[string]any)
+	accounts, _ := result["data"].(map[string]any)["viewer"].(map[string]any)["accounts"].([]any)
-	viewer, _ := data["viewer"].(map[string]any)
-	accounts, _ := viewer["accounts"].([]any)
 	for _, a := range accounts {
 		props, _ := a.(map[string]any)["properties"].([]any)
 		for _, p := range props {
-			pm, ok := p.(map[string]any)
+			pm := p.(map[string]any)
-			if !ok {
-				continue
-			}
 
 			for _, mp := range toSlice(pm["electricityMeterPoints"]) {
 				if tariff := activeAgreementTariff(mp); tariff != nil {
@@ -49,6 +44,7 @@ func getRates(token string) (*tariffRates, error) {
 					rates.ElectricityProductCode, _ = tariff["productCode"].(string)
 					rates.ElectricityTariffCode, _ = tariff["tariffCode"].(string)
 					// HalfHourlyTariff has no unitRate field — detect Agile by absence.
+					_, rates.ElectricityIsAgile = tariff["unitRates"]
 					if _, hasUnit := tariff["unitRate"]; !hasUnit {
 						rates.ElectricityIsAgile = true
 					}
@@ -69,15 +65,8 @@ func getRates(token string) (*tariffRates, error) {
 
 // activeAgreementTariff returns the tariff map for the agreement with validTo == null.
 func activeAgreementTariff(meterPoint any) map[string]any {
-	mp, ok := meterPoint.(map[string]any)
+	for _, ag := range toSlice(meterPoint.(map[string]any)["agreements"]) {
-	if !ok {
+		agm := ag.(map[string]any)
-		return nil
-	}
-	for _, ag := range toSlice(mp["agreements"]) {
-		agm, ok := ag.(map[string]any)
-		if !ok {
-			continue
-		}
 		if agm["validTo"] == nil {
 			tariff, _ := agm["tariff"].(map[string]any)
 			return tariff

cmd/octopus_exporter/rest.go

@@ -2,25 +2,29 @@ package main
 
 import (
 	"encoding/json"
+	"io"
 	"net/http"
 	"net/url"
 )
 
 var octopusREST = "https://api.octopus.energy"
 
-func doREST(path string, params url.Values, key string) (map[string]any, error) {
+func doREST(path string, params url.Values) (map[string]any, error) {
 	u := octopusREST + path
 	if len(params) > 0 {
 		u += "?" + params.Encode()
 	}
-	raw, err := executeWithRetry(func() (*http.Request, error) {
+	req, err := http.NewRequest(http.MethodGet, u, nil)
-		req, err := http.NewRequest(http.MethodGet, u, nil)
+	if err != nil {
-		if err != nil {
+		return nil, err
-			return nil, err
+	}
-		}
+	req.SetBasicAuth(apiKey, "")
-		req.SetBasicAuth(key, "")
+	resp, err := http.DefaultClient.Do(req)
-		return req, nil
+	if err != nil {
-	})
+		return nil, err
+	}
+	defer resp.Body.Close()
+	raw, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return nil, err
 	}

cmd/octopus_exporter/telemetry.go

@@ -3,7 +3,6 @@ package main
 import (
 	"encoding/json"
 	"errors"
-	"fmt"
 )
 
 type telemetryReading struct {
@@ -19,14 +18,13 @@ func getLiveConsumption(token, deviceID string) (*telemetryReading, error) {
 		Query:         "query getSmartMeterTelemetry($meterDeviceId: String!, $start: DateTime, $end: DateTime, $grouping: TelemetryGrouping) {\n  smartMeterTelemetry(deviceId: $meterDeviceId, start: $start, end: $end, grouping: $grouping) {\n    readAt\n    consumption\n    demand\n    __typename\n  }\n}\n",
 	}, token)
 	if err != nil {
+		if err.Error() == "GraphQL error: Signature of the JWT has expired." {
+			return nil, errTokenExpired
+		}
 		return nil, err
 	}
 
-	data, ok := result["data"].(map[string]any)
+	telemetry := toSlice(result["data"].(map[string]any)["smartMeterTelemetry"])
-	if !ok {
-		return nil, fmt.Errorf("unexpected API response: missing data field")
-	}
-	telemetry := toSlice(data["smartMeterTelemetry"])
 	if len(telemetry) == 0 {
 		return nil, errors.New("no telemetry data returned")
 	}

cmd/octopus_exporter/telemetry_test.go

@@ -1,71 +0,0 @@
-package main
-
-import (
-	"fmt"
-	"net/http"
-	"net/http/httptest"
-	"testing"
-)
-
-func TestGetLiveConsumption_Success(t *testing.T) {
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		fmt.Fprint(w, `{"data":{"smartMeterTelemetry":[
-			{"readAt":"2026-04-24T10:00:00Z","consumption":"1.23","demand":"456.7"}
-		]}}`)
-	}))
-	defer srv.Close()
-	octopusGraphQL = srv.URL + "/"
-
-	reading, err := getLiveConsumption("test-token", "device-123")
-	if err != nil {
-		t.Fatalf("unexpected error: %v", err)
-	}
-	if float64(reading.Demand) != 456.7 {
-		t.Errorf("demand: got %v, want 456.7", reading.Demand)
-	}
-	if float64(reading.Consumption) != 1.23 {
-		t.Errorf("consumption: got %v, want 1.23", reading.Consumption)
-	}
-	if reading.ReadAt != "2026-04-24T10:00:00Z" {
-		t.Errorf("readAt: got %q, want %q", reading.ReadAt, "2026-04-24T10:00:00Z")
-	}
-}
-
-func TestGetLiveConsumption_EmptyTelemetry(t *testing.T) {
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		fmt.Fprint(w, `{"data":{"smartMeterTelemetry":[]}}`)
-	}))
-	defer srv.Close()
-	octopusGraphQL = srv.URL + "/"
-
-	_, err := getLiveConsumption("test-token", "device-123")
-	if err == nil {
-		t.Error("expected error for empty telemetry, got nil")
-	}
-}
-
-func TestGetLiveConsumption_MissingDataField(t *testing.T) {
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		fmt.Fprint(w, `{"data":null}`)
-	}))
-	defer srv.Close()
-	octopusGraphQL = srv.URL + "/"
-
-	_, err := getLiveConsumption("test-token", "device-123")
-	if err == nil {
-		t.Error("expected error for null data, got nil")
-	}
-}
-
-func TestGetLiveConsumption_GraphQLError(t *testing.T) {
-	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		fmt.Fprint(w, `{"errors":[{"message":"device not found"}]}`)
-	}))
-	defer srv.Close()
-	octopusGraphQL = srv.URL + "/"
-
-	_, err := getLiveConsumption("test-token", "device-123")
-	if err == nil {
-		t.Error("expected error for GraphQL error, got nil")
-	}
-}