lib/promscrape/discovery/ec2: add ability to filter Availability Zones in ec2_sd_config via az_filters section

docs/CHANGELOG.md

@@ -15,6 +15,8 @@ The following tip changes can be tested by building VictoriaMetrics components f
 
 ## tip
 
+* FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent.html): add ability to specify filters for Availability Zones in [ec2_sd_config](https://prometheus.io/docs/prometheus/latest/configuration/configuration/#ec2_sd_config) via `az_filters` section. This section can contain AZ-specific set of filters in the same way as the existing `filters` section, which is used for filtering EC2 instances. The list of supported AZ-specific filters is available [here](https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DescribeAvailabilityZones.html).
+
 * BUGFIX: [vmctl](https://docs.victoriametrics.com/vmctl.html): properly import InfluxDB measurements if they contain `db` tag. Previously this could result in incomplete import of measurmenet tags. See [this pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/2536). Thanks to @mback2k for the bugfix.
 * BUGFIX: [vmui](https://docs.victoriametrics.com/#vmui): do not reset the selected relative time range when entering new query. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2402#issuecomment-1115817302).
 * BUGFIX: [vmui](https://docs.victoriametrics.com/#vmui): properly show the graph when clicking on `Prometheus` link in Grafana graph editor. Previously the graph wasn't shown until clicking on the `Graph` tab. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/2402#issuecomment-1115830648).

lib/promscrape/discovery/ec2/api.go

@@ -8,9 +8,10 @@ import (
 )
 
 type apiConfig struct {
-	awsConfig *awsapi.Config
-	filters   []awsapi.Filter
-	port      int
+	awsConfig       *awsapi.Config
+	instanceFilters []awsapi.Filter
+	azFilters       []awsapi.Filter
+	port            int
 
 	// A map from AZ name to AZ id.
 	azMap     map[string]string
@@ -37,9 +38,10 @@ func newAPIConfig(sdc *SDConfig) (*apiConfig, error) {
 		return nil, err
 	}
 	cfg := &apiConfig{
-		awsConfig: awsCfg,
-		filters:   sdc.Filters,
-		port:      port,
+		awsConfig:       awsCfg,
+		instanceFilters: sdc.InstanceFilters,
+		azFilters:       sdc.AZFilters,
+		port:            port,
 	}
 	return cfg, nil
 }

lib/promscrape/discovery/ec2/az.go

@@ -30,7 +30,7 @@ func getAZMap(cfg *apiConfig) map[string]string {
 
 func getAvailabilityZones(cfg *apiConfig) ([]AvailabilityZone, error) {
 	// See https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DescribeAvailabilityZones.html
-	azFilters := awsapi.GetFiltersQueryString(cfg.filters, azFiltersWhitelist)
+	azFilters := awsapi.GetFiltersQueryString(cfg.azFilters, azFiltersWhitelist)
 	data, err := cfg.awsConfig.GetEC2APIResponse("DescribeAvailabilityZones", azFilters, "")
 	if err != nil {
 		return nil, fmt.Errorf("cannot obtain availability zones: %w", err)

lib/promscrape/discovery/ec2/ec2.go

@@ -27,8 +27,9 @@ type SDConfig struct {
 	RoleARN string `yaml:"role_arn,omitempty"`
 	// RefreshInterval time.Duration `yaml:"refresh_interval"`
 	// refresh_interval is obtained from `-promscrape.ec2SDCheckInterval` command-line option.
-	Port    *int            `yaml:"port,omitempty"`
-	Filters []awsapi.Filter `yaml:"filters,omitempty"`
+	Port            *int            `yaml:"port,omitempty"`
+	InstanceFilters []awsapi.Filter `yaml:"filters,omitempty"`
+	AZFilters       []awsapi.Filter `yaml:"az_filters,omitempty"`
 }
 
 // GetLabels returns ec2 labels according to sdc.

lib/promscrape/discovery/ec2/instance.go

@@ -29,7 +29,7 @@ func getReservations(cfg *apiConfig) ([]Reservation, error) {
 	// See https://docs.aws.amazon.com/AWSEC2/latest/APIReference/API_DescribeInstances.html
 	var rs []Reservation
 	pageToken := ""
-	instanceFilters := awsapi.GetFiltersQueryString(cfg.filters, nil)
+	instanceFilters := awsapi.GetFiltersQueryString(cfg.instanceFilters, nil)
 	for {
 		data, err := cfg.awsConfig.GetEC2APIResponse("DescribeInstances", instanceFilters, pageToken)
 		if err != nil {