Initial version

.gitignore

@@ -0,0 +1 @@
+aaisp-quota-exporter

README.md

@@ -1,3 +1,11 @@
 # aaisp-quota-exporter
 
-Trivial Prometheus exporter to fetch and plot remaining monthly quota for AAISP users.
+Trivial Prometheus exporter to fetch and plot remaining monthly quota for AAISP
+users. Uses the AAISP API documented at
+[https://support.aa.net.uk/Home::1](https://support.aa.net.uk/Home::1).
+
+The exporter takes an optional `-bind` parameter with `[host]:port` argument.
+It will default to `:9100` (bind to all addresses, port 9100). Metrics are
+available at `/metrics`.
+
+It will update every 5 minutes.

go.mod

@@ -0,0 +1,17 @@
+module src.lwithers.me.uk/go/aaisp-quota-exporter
+
+go 1.20
+
+require github.com/prometheus/client_golang v1.14.0
+
+require (
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
+	github.com/prometheus/client_model v0.3.0 // indirect
+	github.com/prometheus/common v0.41.0 // indirect
+	github.com/prometheus/procfs v0.9.0 // indirect
+	golang.org/x/sys v0.5.0 // indirect
+	google.golang.org/protobuf v1.28.1 // indirect
+)

go.sum

@@ -0,0 +1,30 @@
+github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
+github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
+github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=
+github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
+github.com/golang/protobuf v1.3.5/go.mod h1:6O5/vntMXwX2lRkT1hjjk0nAC1IDOTvTlVgjlRvqsdk=
+github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
+github.com/golang/protobuf v1.5.2 h1:ROPKBNFfQgOUMifHyP+KYbvpjbdoFNs+aK7DXlji0Tw=
+github.com/golang/protobuf v1.5.2/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
+github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/matttproud/golang_protobuf_extensions v1.0.4 h1:mmDVorXM7PCGKw94cs5zkfA9PSy5pEvNWRP0ET0TIVo=
+github.com/matttproud/golang_protobuf_extensions v1.0.4/go.mod h1:BSXmuO+STAnVfrANrmjBb36TMTDstsz7MSK+HVaYKv4=
+github.com/prometheus/client_golang v1.14.0 h1:nJdhIvne2eSX/XRAFV9PcvFFRbrjbcTUj0VP62TMhnw=
+github.com/prometheus/client_golang v1.14.0/go.mod h1:8vpkKitgIVNcqrRBWh1C4TIUQgYNtG/XQE4E/Zae36Y=
+github.com/prometheus/client_model v0.3.0 h1:UBgGFHqYdG/TPFD1B1ogZywDqEkwp3fBMvqdiQ7Xew4=
+github.com/prometheus/client_model v0.3.0/go.mod h1:LDGWKZIo7rky3hgvBe+caln+Dr3dPggB5dvjtD7w9+w=
+github.com/prometheus/common v0.41.0 h1:npo01n6vUlRViIj5fgwiK8vlNIh8bnoxqh3gypKsyAw=
+github.com/prometheus/common v0.41.0/go.mod h1:xBwqVerjNdUDjgODMpudtOMwlOwf2SaTr1yjz4b7Zbc=
+github.com/prometheus/procfs v0.9.0 h1:wzCHvIvM5SxWqYvwgVL7yJY8Lz3PKn49KQtpgMYJfhI=
+github.com/prometheus/procfs v0.9.0/go.mod h1:+pB4zwohETzFnmlpe6yd2lSc+0/46IYZRB/chUwxUZY=
+golang.org/x/sync v0.0.0-20181221193216-37e7f081c4d4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
+golang.org/x/sys v0.5.0 h1:MUK/U/4lj1t1oPg0HfuXDN/Z1wv31ZJ/YcPiGccS4DU=
+golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
+google.golang.org/protobuf v1.26.0/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
+google.golang.org/protobuf v1.28.1 h1:d0NfwRgPtno5B1Wa6L2DAG+KivqkdutMf1UhdNx175w=
+google.golang.org/protobuf v1.28.1/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=

main.go

@@ -0,0 +1,108 @@
+package main
+
+import (
+	"crypto/tls"
+	"encoding/json"
+	"errors"
+	"flag"
+	"fmt"
+	"net/http"
+	"os"
+	"time"
+
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promauto"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+)
+
+const (
+	period  = 5 * time.Minute
+	timeout = 10 * time.Second
+	api     = "https://quota.aa.net.uk"
+)
+
+var (
+	cl   *http.Client
+	bind = flag.String("bind", ":9100", "[host]:port to bind to.")
+
+	monthlyQuotaBytes = promauto.NewGauge(prometheus.GaugeOpts{
+		Name: "aaisp_quota_monthly_bytes",
+		Help: "Monthly quota provided by AAISP.",
+	})
+	quotaRemainingBytes = promauto.NewGauge(prometheus.GaugeOpts{
+		Name: "aaisp_quota_remaining_bytes",
+		Help: "Number of bytes remaining on this month's AAISP quota.",
+	})
+)
+
+func main() {
+	flag.Parse()
+
+	cl = &http.Client{
+		Transport: &http.Transport{
+			TLSClientConfig: &tls.Config{
+				MinVersion: tls.VersionTLS12,
+			},
+		},
+		Timeout: timeout,
+	}
+
+	go collect()
+
+	http.Handle("/metrics", promhttp.Handler())
+	err := http.ListenAndServe(*bind, nil)
+	switch {
+	case errors.Is(err, http.ErrServerClosed), err == nil:
+		// clean shutdown
+	default:
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
+
+func collect() {
+	for {
+		quota, err := getQuota()
+		if err != nil {
+			fmt.Fprintln(os.Stderr, err)
+		} else {
+			monthlyQuotaBytes.Set(quota.MonthlyQuotaBytes)
+			quotaRemainingBytes.Set(quota.QuotaRemainingBytes)
+		}
+
+		now := time.Now()
+		align := now.Truncate(period).Add(period)
+		s := align.Sub(now)
+		if s > 0 {
+			time.Sleep(s)
+		}
+	}
+}
+
+type quotaResponse struct {
+	MonthlyQuotaBytes   float64 `json:"monthly_quota"`
+	QuotaRemainingBytes float64 `json:"quota_remaining"`
+}
+
+func getQuota() (quotaResponse, error) {
+	req, err := http.NewRequest(http.MethodGet, api, nil)
+	if err != nil {
+		return quotaResponse{}, err
+	}
+	req.Header.Set("Accept", "application/json")
+	req.Header.Set("User-Agent", "src.lwithers.me.uk/go/aaisp-quota-exporter v1.0")
+
+	resp, err := cl.Do(req)
+	if err != nil {
+		return quotaResponse{}, err
+	}
+	defer resp.Body.Close()
+
+	var q quotaResponse
+	dec := json.NewDecoder(resp.Body)
+	if err := dec.Decode(&q); err != nil {
+		return quotaResponse{}, fmt.Errorf("%s: could not decode response: %w", api, err)
+	}
+
+	return q, nil
+}