Azure: Add Blob cost query

AGENTS.md

@@ -21,7 +21,7 @@ cmd/exporter/exporter.go             # Entrypoint: flags, provider selection, HT
 pkg/provider/provider.go             # Provider, Collector, Registry interfaces
 pkg/aws/aws.go                       # AWS: S3, EC2, RDS, NATGATEWAY, ELB, VPC
 pkg/google/gcp.go                    # GCP: GCS, GKE, CLB, SQL, VPC
-pkg/azure/azure.go                   # Azure: AKS
+pkg/azure/azure.go                   # Azure: AKS, blob
 pkg/gatherer/gatherer.go             # Wraps Collect(): duration, errors, metadata metrics
 pkg/utils/consts.go                  # Shared metric suffixes, HoursInMonth, GenerateDesc()
 cmd/dashboards/main.go               # Dashboard generation (grafana-foundation-sdk)
@@ -58,7 +58,8 @@ Rule: Never push to `main`.
 ```bash
 go run cmd/exporter/exporter.go -provider gcp -project-id=$GCP_PROJECT_ID -gcp.services GKE,GCS
 go run cmd/exporter/exporter.go -provider aws -aws.profile $AWS_PROFILE -aws.services EC2,S3
-go run cmd/exporter/exporter.go -provider azure -azure.subscription-id $AZ_SUBSCRIPTION_ID
+go run cmd/exporter/exporter.go -provider azure -azure.subscription-id $AZ_SUBSCRIPTION_ID -azure.services AKS
+go run cmd/exporter/exporter.go -provider azure -azure.subscription-id $AZ_SUBSCRIPTION_ID -azure.services blob
 ```
 
 ### Adding a collector

cmd/exporter/exporter.go

@@ -75,7 +75,7 @@ func providerFlags(fs *flag.FlagSet, cfg *config.Config) {
 	fs.Var(config.NewDeprecatedStringSliceFlag(&cfg.Providers.GCP.Projects, &cfg.Providers.GCP.BucketProjectsDeprecated), "gcp.bucket-projects", "GCP project(s). (deprecated: use --gcp.projects instead)")
 	fs.Var(&cfg.Providers.AWS.Services, "aws.services", "AWS service(s).")
 	fs.Var(&cfg.Providers.AWS.ExcludeRegions, "aws.exclude-regions", "AWS region(s) to exclude from cost collection.")
-	fs.Var(&cfg.Providers.Azure.Services, "azure.services", "Azure service(s).")
+	fs.Var(&cfg.Providers.Azure.Services, "azure.services", "Azure service(s): AKS, blob (comma-separated and/or repeat flag; case-insensitive).")
 	fs.Var(&cfg.Providers.GCP.Services, "gcp.services", "GCP service(s).")
 	flag.StringVar(&cfg.Providers.AWS.Region, "aws.region", "", "AWS region")
 	flag.StringVar(&cfg.Providers.AWS.RoleARN, "aws.roleARN", "", "Optional AWS role ARN to assume for cross-account access.")
@@ -242,7 +242,8 @@ func selectProviderWith(
 		return newAzure(ctx, &azure.Config{
 			Logger:           cfg.Logger,
 			SubscriptionId:   cfg.Providers.Azure.SubscriptionId,
-			Services:         cfg.Providers.Azure.Services,
+			ScrapeInterval:   cfg.Collector.ScrapeInterval,
+			Services:         strings.Split(cfg.Providers.Azure.Services.String(), ","),
 			CollectorTimeout: collectorTimeout,
 		})
 	case "aws":

docs/README.md

@@ -11,6 +11,6 @@
   - [Providers](metrics/providers.md)
   - **AWS:** [EC2](metrics/aws/ec2.md), [S3](metrics/aws/s3.md), [RDS](metrics/aws/rds.md), [MSK](metrics/aws/msk.md), [ELB](metrics/aws/elb.md), [NAT Gateway](metrics/aws/natgateway.md), [VPC](metrics/aws/vpc.md)
   - **GCP:** [GKE](metrics/gcp/gke.md), [GCS](metrics/gcp/gcs.md), [Cloud SQL](metrics/gcp/cloudsql.md), [Managed Kafka](metrics/gcp/managedkafka.md), [CLB](metrics/gcp/clb.md), [VPC](metrics/gcp/vpc.md)
-  - **Azure:** [AKS](metrics/azure/aks.md)
+  - **Azure:** [AKS](metrics/azure/aks.md), [blob](metrics/azure/blob.md)
 - [Deploying](deploying/aws/README.md) - Run the exporter
   - [AWS](deploying/aws/README.md) — IRSA, Helm, cross-account access

docs/metrics/README.md

@@ -22,3 +22,4 @@
 ## Azure Services
 
 - **[AKS](./azure/aks.md)** - Azure Kubernetes Service VM instances and managed disks
+- **[Blob](./azure/blob.md)** - Azure Blob Storage (cost metrics registered; no series until Cost Management)

docs/metrics/azure/blob.md

@@ -0,0 +1,11 @@
+# Azure Blob Storage metrics
+
+Pass `blob` in `--azure.services` to enable this collector. Matching is case-insensitive.
+
+The collector defines a storage cost `GaugeVec` that the Azure provider includes in its `Describe` and `Collect` fan-out (same gatherer pattern as `azure_aks`). `Collect` calls `StorageCostQuerier.QueryBlobStorage` when `ScrapeInterval` has elapsed since the last successful query (similar billing refresh cadence to `pkg/aws/s3`). Each query uses a **30-day** lookback (`defaultQueryLookback` in `pkg/azure/blob/cost_query.go`). Cached rows are applied to the gauge every scrape. `Config.CostQuerier` supplies the querier; when it is nil the collector uses a no-op querier (no rows). The parent Azure collector forwards `StorageGauge.Collect(ch)` so blob cost metrics share one registration path with the rest of the Azure exporter. Scrape instrumentation publishes `cloudcost_exporter_collector_*` with label `collector="azure_blob"`.
+
+## Cost metrics
+
+| Metric name | Metric type | Description | Labels |
+|-------------|-------------|-------------|--------|
+| cloudcost_azure_blob_storage_by_location_usd_per_gibyte_hour | Gauge | Storage cost rate for Blob Storage by region and class. Cost represented in USD/(GiB*h) | `region`=&lt;Azure region&gt;<br/> `class`=&lt;Blob access tier or storage class&gt; |

go.mod

@@ -10,6 +10,7 @@ require (
 	github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.13.1
 	github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/compute/armcompute/v7 v7.3.0
 	github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/containerservice/armcontainerservice/v8 v8.2.0
+	github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/costmanagement/armcostmanagement v1.1.1
 	github.com/Azure/go-autorest/autorest/to v0.4.1
 	github.com/aws/aws-sdk-go-v2 v1.41.4
 	github.com/aws/aws-sdk-go-v2/config v1.32.12
@@ -39,6 +40,7 @@ require (
 
 require (
 	cloud.google.com/go/managedkafka v0.8.1
+	github.com/Azure/azure-sdk-for-go/sdk/azcore v1.20.0
 	github.com/aws/aws-sdk-go-v2/service/kafka v1.49.0
 )
 
@@ -50,7 +52,6 @@ require (
 	cloud.google.com/go/compute/metadata v0.9.0 // indirect
 	cloud.google.com/go/iam v1.6.0 // indirect
 	cloud.google.com/go/longrunning v0.8.0 // indirect
-	github.com/Azure/azure-sdk-for-go/sdk/azcore v1.20.0 // indirect
 	github.com/Azure/azure-sdk-for-go/sdk/internal v1.11.2 // indirect
 	github.com/Azure/go-autorest v14.2.0+incompatible // indirect
 	github.com/AzureAD/microsoft-authentication-library-for-go v1.6.0 // indirect

go.sum

@@ -38,6 +38,8 @@ github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/compute/armcompute/v7 v7.3
 github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/compute/armcompute/v7 v7.3.0/go.mod h1:e4RAYykLIz73CF52KhSooo4whZGXvXrD09m0jkgnWiU=
 github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/containerservice/armcontainerservice/v8 v8.2.0 h1:aXzpyYcHexm3eSlvy6g7r3cshXtGcEg6VJpOdrN0Us0=
 github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/containerservice/armcontainerservice/v8 v8.2.0/go.mod h1:vs/o7so4c3csg/CM0LDrqxSKDxcKgeYbgI3zaL6vu7U=
+github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/costmanagement/armcostmanagement v1.1.1 h1:ehSLdbLah6kk6HTVc6e/lrbmbz7MMbpNxkOd3OYlhB0=
+github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/costmanagement/armcostmanagement v1.1.1/go.mod h1:Am1cUioOk0HdZIsjpXJkQ4RIeQbwYsW6LkNIc5z/5XY=
 github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/internal/v3 v3.1.0 h1:2qsIIvxVT+uE6yrNldntJKlLRgxGbZ85kgtz5SNBhMw=
 github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/internal/v3 v3.1.0/go.mod h1:AW8VEadnhw9xox+VaVd9sP7NjzOAnaZBLRH6Tq3cJ38=
 github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/resources/armresources v1.2.0 h1:Dd+RhdJn0OTtVGaeDLZpcumkIVCtA/3/Fo42+eoYvVM=

pkg/azure/azure.go

@@ -12,6 +12,7 @@ import (
 	"github.com/prometheus/client_golang/prometheus"
 
 	"github.com/grafana/cloudcost-exporter/pkg/azure/aks"
+	"github.com/grafana/cloudcost-exporter/pkg/azure/blob"
 	"github.com/grafana/cloudcost-exporter/pkg/azure/client"
 	"github.com/grafana/cloudcost-exporter/pkg/collectormetrics"
 	"github.com/grafana/cloudcost-exporter/pkg/provider"
@@ -65,6 +66,7 @@ type Config struct {
 	Region string
 
 	SubscriptionId string
+	ScrapeInterval time.Duration
 
 	CollectorTimeout time.Duration
 	Services         []string
@@ -90,15 +92,35 @@ func New(ctx context.Context, config *Config) (*Azure, error) {
 		return nil, err
 	}
 
-	// Collector Registration
+	// Collector Registration (--azure.services matching is case-insensitive).
 	for _, svc := range config.Services {
-		switch strings.ToUpper(svc) {
-		case "AKS":
+		svc = strings.TrimSpace(svc)
+		if svc == "" {
+			continue
+		}
+		switch {
+		case strings.EqualFold(svc, "AKS"):
 			collector, err := aks.New(ctx, &aks.Config{
 				Logger: logger,
 			}, azClientWrapper)
 			if err != nil {
-				return nil, err
+				logger.LogAttrs(ctx, slog.LevelError, "Error creating collector",
+					slog.String("service", svc),
+					slog.String("message", err.Error()))
+				continue
+			}
+			collectors = append(collectors, collector)
+		case strings.EqualFold(svc, "blob"):
+			collector, err := blob.New(&blob.Config{
+				Logger:         logger,
+				SubscriptionId: config.SubscriptionId,
+				ScrapeInterval: config.ScrapeInterval,
+			})
+			if err != nil {
+				logger.LogAttrs(ctx, slog.LevelError, "Error creating collector",
+					slog.String("service", svc),
+					slog.String("message", err.Error()))
+				continue
 			}
 			collectors = append(collectors, collector)
 		default:

pkg/azure/blob/blob.go

@@ -0,0 +1,131 @@
+package blob
+
+import (
+	"context"
+	"log/slog"
+	"sync"
+	"time"
+
+	"github.com/grafana/cloudcost-exporter/pkg/provider"
+	"github.com/prometheus/client_golang/prometheus"
+
+	cloudcost_exporter "github.com/grafana/cloudcost-exporter"
+)
+
+const subsystem = "azure_blob"
+
+// metrics holds Prometheus collectors for blob cost rates. Vectors are not registered on the root registry;
+// Azure's top-level Collector gathers them via Collect → GaugeVec.Collect (same pattern as pkg/azure/aks).
+type metrics struct {
+	StorageGauge *prometheus.GaugeVec
+	// Planned future work: operation request rate (parity with S3/GCS cloudcost_*_operation_by_location_usd_per_krequest).
+	// OperationsGauge *prometheus.GaugeVec
+}
+
+func newMetrics() metrics {
+	m := metrics{
+		StorageGauge: prometheus.NewGaugeVec(prometheus.GaugeOpts{
+			Name: prometheus.BuildFQName(cloudcost_exporter.MetricPrefix, subsystem, "storage_by_location_usd_per_gibyte_hour"),
+			Help: "Storage cost of blob objects by region and class. Cost represented in USD/(GiB*h). Populated when CostQuerier returns data.",
+		},
+			[]string{"region", "class"},
+		),
+	}
+
+	// Planned future work: register operation cost per 1k requests (labels region, class, tier) when Cost Management dimensions support it.
+	// m.OperationsGauge = prometheus.NewGaugeVec(prometheus.GaugeOpts{
+	// 	Name: prometheus.BuildFQName(cloudcost_exporter.MetricPrefix, subsystem, "operation_by_location_usd_per_krequest"),
+	// 	Help: "Operation cost of blob objects by region, class, and tier. Cost represented in USD/(1k req). No samples until Cost Management is integrated.",
+	// },
+	// 	[]string{"region", "class", "tier"},
+	// )
+
+	return m
+}
+
+// Collector implements provider.Collector for Azure Blob Storage cost metrics.
+type Collector struct {
+	logger         *slog.Logger
+	metrics        metrics
+	querier        StorageCostQuerier
+	subscriptionID string
+	scrapeInterval time.Duration
+
+	mu          sync.Mutex
+	cachedRows  []StorageCostRow
+	nextRefresh time.Time // QueryBlobStorage when time.Now is on or after this (S3 billing refresh pattern).
+}
+
+// Config holds settings for the blob collector.
+type Config struct {
+	Logger         *slog.Logger
+	SubscriptionId string
+	ScrapeInterval time.Duration
+	// CostQuerier optional; when nil a no-op is used until Azure Cost Management is wired (e.g. from pkg/azure).
+	CostQuerier StorageCostQuerier
+}
+
+// New builds a blob collector. Subscription and scrape interval are stored for refresh logic; cost data comes from CostQuerier (default no-op).
+func New(cfg *Config) (*Collector, error) {
+	interval := cfg.ScrapeInterval
+	if interval <= 0 {
+		interval = time.Hour
+	}
+	q := cfg.CostQuerier
+	if q == nil {
+		q = noopStorageCostQuerier{}
+	}
+	return &Collector{
+		logger:         cfg.Logger.With("collector", "blob"),
+		metrics:        newMetrics(),
+		querier:        q,
+		subscriptionID: cfg.SubscriptionId,
+		scrapeInterval: interval,
+		// First Collect runs a query immediately (same idea as pkg/aws/s3 nextScrape).
+		nextRefresh: time.Now().Add(-interval),
+	}, nil
+}
+
+// Collect queries cost rows, updates the storage vec, then forwards metrics on ch for the parent gatherer.
+func (c *Collector) Collect(ctx context.Context, ch chan<- prometheus.Metric) error {
+	c.logger.LogAttrs(ctx, slog.LevelInfo, "collecting metrics")
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	now := time.Now()
+	if !now.Before(c.nextRefresh) {
+		rows, err := c.querier.QueryBlobStorage(ctx, c.subscriptionID, defaultQueryLookback)
+		if err != nil {
+			return err
+		}
+		c.cachedRows = rows
+		c.nextRefresh = now.Add(c.scrapeInterval)
+	}
+	c.applyRowsToGauge(c.cachedRows)
+	c.metrics.StorageGauge.Collect(ch)
+	return nil
+}
+
+func (c *Collector) applyRowsToGauge(rows []StorageCostRow) {
+	for _, row := range rows {
+		c.metrics.StorageGauge.WithLabelValues(row.Region, row.Class).Set(row.Rate)
+	}
+}
+
+// Describe satisfies provider.Collector.
+func (c *Collector) Describe(ch chan<- *prometheus.Desc) error {
+	c.metrics.StorageGauge.Describe(ch)
+	// Planned future work: c.metrics.OperationsGauge.Describe(ch)
+	return nil
+}
+
+// Name returns the collector subsystem name for operational metrics.
+func (c *Collector) Name() string {
+	return subsystem
+}
+
+// Register satisfies provider.Collector. Does not register cost metrics on the registry (avoids duplicate Desc
+// with Azure's Describe fan-out; metrics are collected via Collect → StorageGauge.Collect).
+func (c *Collector) Register(_ provider.Registry) error {
+	c.logger.LogAttrs(context.Background(), slog.LevelInfo, "registering collector")
+	return nil
+}