Handle rate limit error on startup.

Author: jbub

go.mod

@@ -3,7 +3,8 @@ module github.com/jbub/foxesscloud_exporter
 go 1.23
 
 require (
-	github.com/jbub/foxesscloud v0.1.0
+	github.com/jbub/foxesscloud v0.2.0
+	github.com/oklog/run v1.1.0
 	github.com/prometheus/client_golang v1.20.4
 	github.com/prometheus/common v0.60.0
 	github.com/urfave/cli/v2 v2.27.4
@@ -16,7 +17,6 @@ require (
 	github.com/cpuguy83/go-md2man/v2 v2.0.4 // indirect
 	github.com/klauspost/compress v1.17.9 // indirect
 	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
-	github.com/oklog/run v1.1.0 // indirect
 	github.com/prometheus/client_model v0.6.1 // indirect
 	github.com/prometheus/procfs v0.15.1 // indirect
 	github.com/russross/blackfriday/v2 v2.1.0 // indirect

go.sum

@@ -8,8 +8,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
-github.com/jbub/foxesscloud v0.1.0 h1:TBHGUliVggEizJvGrMJfKRMLABmBb7SyMHQkzKKctHU=
-github.com/jbub/foxesscloud v0.1.0/go.mod h1:Lc1eomdGTxjV8UZ04/rnTwG9nJw3EsV/I95oGK+uHWs=
+github.com/jbub/foxesscloud v0.2.0 h1:ZF16lcG7hu6KafDVKQKXbRgePM4mSrsMqszxBnrUjWY=
+github.com/jbub/foxesscloud v0.2.0/go.mod h1:Lc1eomdGTxjV8UZ04/rnTwG9nJw3EsV/I95oGK+uHWs=
 github.com/klauspost/compress v1.17.9 h1:6KIumPrER1LHsvBVuDa0r5xaG0Es51mhhB9BQB2qeMA=
 github.com/klauspost/compress v1.17.9/go.mod h1:Di0epgTjJY877eYKx5yC51cX2A2Vl2ibi7bDH9ttBbw=
 github.com/kylelemons/godebug v1.1.0 h1:RPNrshWIDI6G2gRW9EHilWtl7Z6Sb1BR0xunSBf0SNc=

internal/collector/exporter.go

@@ -2,6 +2,7 @@ package collector
 
 import (
 	"context"
+	"errors"
 	"fmt"
 	"maps"
 	"strings"
@@ -66,7 +67,7 @@ func New(cfg config.Config, log *zap.Logger, client *foxesscloud.Client) (*Expor
 
 func (e *Exporter) Start() error {
 	ctx := context.Background()
-	data, err := e.fetchInverters(ctx)
+	data, err := e.fetchInvertersInitial(ctx)
 	if err != nil {
 		return fmt.Errorf("could not fetch inverter data: %w", err)
 	}
@@ -133,6 +134,21 @@ func (e *Exporter) buildLabels(inverterSN string) prometheus.Labels {
 	return labels
 }
 
+func (e *Exporter) fetchInvertersInitial(ctx context.Context) ([]metricData, error) {
+	data, err := e.fetchInverters(ctx)
+	if err != nil {
+		// in case initial fetch fails on rate limit, we want the program to continue
+		// the next tick will retry the fetch instead of exiting the program
+		var errRate *foxesscloud.RateLimitExceededError
+		if errors.As(err, &errRate) {
+			e.log.Error("rate limit exceeded", zap.Error(err))
+			return data, nil
+		}
+		return nil, err
+	}
+	return data, nil
+}
+
 func (e *Exporter) fetchInverters(ctx context.Context) ([]metricData, error) {
 	ctx, cancel := context.WithTimeout(ctx, e.timeout)
 	defer cancel()