[receiver/azuremonitorreceiver] feat: multi subscriptions support and automatic discovery

Co-authored-by: Joshua MacDonald <[email protected]>
Signed-off-by: Célian Garcia <[email protected]>

Author: celian-garcia

.chloggen/feat_discovery.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: breaking
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: receiver/azuremonitorreceiver
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "multi subscriptions support and automatic discovery"
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [36612]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

receiver/azuremonitorreceiver/README.md

@@ -18,7 +18,8 @@ This receiver scrapes Azure Monitor API for resources metrics.
 
 The following settings are required:
 
-- `subscription_id`
+- `subscription_ids`: list of subscriptions on which the resource's metrics are collected
+- or `discover_subscriptions`: (default = `false`) If set to true, will collect metrics from all subscriptions in the tenant.
 
 The following settings are optional:
 
@@ -78,7 +79,7 @@ Using [Service Principal](https://learn.microsoft.com/en-us/azure/developer/go/a
 ```yaml
 receivers:
   azuremonitor:
-    subscription_id: "${subscription_id}"
+    subscription_ids: ["${subscription_id}"]
     tenant_id: "${tenant_id}"
     client_id: "${client_id}"
     client_secret: "${env:CLIENT_SECRET}"
@@ -98,7 +99,7 @@ Using [Azure Workload Identity](https://learn.microsoft.com/en-us/azure/develope
 ```yaml
 receivers:
   azuremonitor:
-    subscription_id: "${subscription_id}"
+    subscription_ids: ["${subscription_id}"]
     auth: "workload_identity"
     tenant_id: "${env:AZURE_TENANT_ID}"
     client_id: "${env:AZURE_CLIENT_ID}"
@@ -110,7 +111,7 @@ Using [Managed Identity](https://learn.microsoft.com/en-us/azure/developer/go/az
 ```yaml
 receivers:
   azuremonitor:
-    subscription_id: "${subscription_id}"
+    subscription_ids: ["${subscription_id}"]
     auth: "managed_identity"
     client_id: "${env:AZURE_CLIENT_ID}"
 ```
@@ -120,7 +121,7 @@ Using [Environment Variables](https://learn.microsoft.com/en-us/azure/developer/
 ```yaml
 receivers:
   azuremonitor:
-    subscription_id: "${subscription_id}"
+    subscription_ids: ["${subscription_id}"]
     auth: "default_credentials"
 ```
 

receiver/azuremonitorreceiver/config.go

@@ -21,12 +21,12 @@ const (
 
 var (
 	// Predefined error responses for configuration validation failures
-	errMissingTenantID       = errors.New(`TenantID" is not specified in config`)
-	errMissingSubscriptionID = errors.New(`SubscriptionID" is not specified in config`)
-	errMissingClientID       = errors.New(`ClientID" is not specified in config`)
-	errMissingClientSecret   = errors.New(`ClientSecret" is not specified in config`)
-	errMissingFedTokenFile   = errors.New(`FederatedTokenFile is not specified in config`)
-	errInvalidCloud          = errors.New(`Cloud" is invalid`)
+	errMissingTenantID        = errors.New(`"TenantID" is not specified in config`)
+	errMissingSubscriptionIDs = errors.New(`neither "SubscriptionIDs" nor "DiscoverSubscription" is specified in the config`)
+	errMissingClientID        = errors.New(`"ClientID" is not specified in config`)
+	errMissingClientSecret    = errors.New(`"ClientSecret" is not specified in config`)
+	errMissingFedTokenFile    = errors.New(`"FederatedTokenFile"" is not specified in config`)
+	errInvalidCloud           = errors.New(`"Cloud" is invalid`)
 
 	monitorServices = []string{
 		"Microsoft.EventGrid/eventSubscriptions",
@@ -240,7 +240,8 @@ type Config struct {
 	scraperhelper.ControllerConfig    `mapstructure:",squash"`
 	MetricsBuilderConfig              metadata.MetricsBuilderConfig `mapstructure:",squash"`
 	Cloud                             string                        `mapstructure:"cloud"`
-	SubscriptionID                    string                        `mapstructure:"subscription_id"`
+	SubscriptionIDs                   []string                      `mapstructure:"subscription_ids"`
+	DiscoverSubscriptions             bool                          `mapstructure:"discover_subscriptions"`
 	Authentication                    string                        `mapstructure:"auth"`
 	TenantID                          string                        `mapstructure:"tenant_id"`
 	ClientID                          string                        `mapstructure:"client_id"`
@@ -266,8 +267,8 @@ const (
 
 // Validate validates the configuration by checking for missing or invalid fields
 func (c Config) Validate() (err error) {
-	if c.SubscriptionID == "" {
-		err = multierr.Append(err, errMissingSubscriptionID)
+	if len(c.SubscriptionIDs) == 0 && !c.DiscoverSubscriptions {
+		err = multierr.Append(err, errMissingSubscriptionIDs)
 	}
 
 	switch c.Authentication {

receiver/azuremonitorreceiver/go.mod

@@ -7,6 +7,7 @@ require (
 	github.com/Azure/azure-sdk-for-go/sdk/azidentity v1.8.2
 	github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/monitor/armmonitor v0.11.0
 	github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/resources/armresources v1.2.0
+	github.com/Azure/azure-sdk-for-go/sdk/resourcemanager/resources/armsubscriptions v1.3.0
 	github.com/google/go-cmp v0.7.0
 	github.com/open-telemetry/opentelemetry-collector-contrib/pkg/golden v0.122.0
 	github.com/open-telemetry/opentelemetry-collector-contrib/pkg/pdatatest v0.122.0

receiver/azuremonitorreceiver/go.sum

@@ -108,16 +108,7 @@ func (mb *MetricsBuilder) updateCapacity(rm pmetric.ResourceMetrics) {
 // ResourceMetricsOption applies changes to provided resource metrics.
 type ResourceMetricsOption func(ResourceAttributesSettings, pmetric.ResourceMetrics)
 
-// WithAzureMonitorSubscriptionID sets provided value as "azuremonitor.subscription_id" attribute for current resource.
-func WithAzureMonitorSubscriptionID(val string) ResourceMetricsOption {
-	return func(ras ResourceAttributesSettings, rm pmetric.ResourceMetrics) {
-		if ras.AzureMonitorSubscriptionID.Enabled {
-			rm.Resource().Attributes().PutStr("azuremonitor.subscription_id", val)
-		}
-	}
-}
-
-// WithAzuremonitorTenantID sets provided value as "azuremonitor.tenant_id" attribute for current resource.
+// WithAzureMonitorTenantID sets provided value as "azuremonitor.tenant_id" attribute for current resource.
 func WithAzureMonitorTenantID(val string) ResourceMetricsOption {
 	return func(ras ResourceAttributesSettings, rm pmetric.ResourceMetrics) {
 		if ras.AzureMonitorTenantID.Enabled {
@@ -209,6 +200,7 @@ func (mb *MetricsBuilder) addMetric(resourceMetricID, logicalMetricID, unit stri
 }
 
 func (mb *MetricsBuilder) AddDataPoint(
+	subscriptionID,
 	resourceID,
 	metric,
 	aggregation,
@@ -218,7 +210,7 @@ func (mb *MetricsBuilder) AddDataPoint(
 	val float64,
 ) {
 	logicalMetricID := getLogicalMetricID(metric, aggregation)
-	resourceMetricID := getLogicalResourceMetricID(resourceID, logicalMetricID)
+	resourceMetricID := getLogicalResourceMetricID(subscriptionID, resourceID, logicalMetricID)
 
 	m, exists := mb.getMetric(resourceMetricID)
 	if !exists {
@@ -232,6 +224,11 @@ func (mb *MetricsBuilder) AddDataPoint(
 	dp.SetStartTimestamp(mb.startTime)
 	dp.SetTimestamp(ts)
 	dp.SetDoubleValue(val)
+
+	if mb.resourceAttributesSettings.AzureMonitorSubscriptionID.Enabled {
+		dp.Attributes().PutStr("azuremonitor.subscription_id", subscriptionID)
+	}
+
 	dp.Attributes().PutStr("azuremonitor.resource_id", resourceID)
 	for key, value := range attributes {
 		dp.Attributes().PutStr(key, *value)
@@ -242,8 +239,8 @@ func getLogicalMetricID(metric, aggregation string) string {
 	return strings.ToLower(fmt.Sprintf("%s%s_%s", metricsPrefix, strings.ReplaceAll(metric, " ", "_"), aggregation))
 }
 
-func getLogicalResourceMetricID(resourceID, logicalMetricID string) string {
-	return fmt.Sprintf("%s/%s", strings.ToLower(resourceID), logicalMetricID)
+func getLogicalResourceMetricID(subscriptionID, resourceID, logicalMetricID string) string {
+	return fmt.Sprintf("%s/%s/%s", strings.ToLower(subscriptionID), strings.ToLower(resourceID), logicalMetricID)
 }
 
 func (mb *MetricsBuilder) EmitAllMetrics(ils pmetric.ScopeMetrics) {