lib/promscrape/discovery/dockerswarm: fix discovery filters being applied to all objects (#3632)

* lib/promscrape/discovery/dockerswarm: fix discovery filters being applied to all objects

Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>

* Update docs/CHANGELOG.md

Signed-off-by: Zakhar Bessarab <z.bessarab@victoriametrics.com>
Co-authored-by: Aliaksandr Valialkin <valyala@victoriametrics.com>

docs/CHANGELOG.md

@@ -15,6 +15,7 @@ The following tip changes can be tested by building VictoriaMetrics components f
 
 ## v1.79.x long-time support release (LTS)
 
+* BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent.html): [dockerswarm_sd_configs](https://docs.victoriametrics.com/sd_configs.html#dockerswarm_sd_configs): apply `filters` only to objects of the specified `role`. Previously filters were applied to all the objects, which could cause errors when different types of objects were used with filters that were not compatible with them. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3579).
 * BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent.html): suppress all the scrape errors when `-promscrape.suppressScrapeErrors` is enabled. Previously some scrape errors were logged even if `-promscrape.suppressScrapeErrors` flag was set.
 * BUGFIX: [vmagent](https://docs.victoriametrics.com/vmagent.html): consistently put the scrape url with scrape target labels to all error logs for failed scrapes. Previously some failed scrapes were logged without this information.
 * BUGFIX: [MetricsQL](https://docs.victoriametrics.com/MetricsQL.html): properly parse `M` and `Mi` suffixes as `1e6` multipliers in `1M` and `1Mi` numeric constants. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/3664). The issue has been introduced in [v1.79.7](https://docs.victoriametrics.com/CHANGELOG.html#v1797).

lib/promscrape/discovery/dockerswarm/api.go

@@ -16,6 +16,9 @@ type apiConfig struct {
 	client *discoveryutils.Client
 	port   int
 
+	// role is the type of objects to discover.
+	role string
+
 	// filtersQueryArg contains escaped `filters` query arg to add to each request to Docker Swarm API.
 	filtersQueryArg string
 }
@@ -49,11 +52,12 @@ func newAPIConfig(sdc *SDConfig, baseDir string) (*apiConfig, error) {
 		return nil, fmt.Errorf("cannot create HTTP client for %q: %w", sdc.Host, err)
 	}
 	cfg.client = client
+	cfg.role = sdc.Role
 	return cfg, nil
 }
 
-func (cfg *apiConfig) getAPIResponse(path string) ([]byte, error) {
+func (cfg *apiConfig) getAPIResponse(path, filtersQueryArg string) ([]byte, error) {
-	if len(cfg.filtersQueryArg) > 0 {
+	if len(filtersQueryArg) > 0 {
 		separator := "?"
 		if strings.Contains(path, "?") {
 			separator = "&"

lib/promscrape/discovery/dockerswarm/dockerswarm.go

@@ -14,6 +14,12 @@ var SDCheckInterval = flag.Duration("promscrape.dockerswarmSDCheckInterval", 30*
 	"This works only if dockerswarm_sd_configs is configured in '-promscrape.config' file. "+
 	"See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#dockerswarm_sd_config for details")
 
+const (
+	roleTasks    = "tasks"
+	roleServices = "services"
+	roleNodes    = "nodes"
+)
+
 // SDConfig represents docker swarm service discovery configuration
 //
 // See https://prometheus.io/docs/prometheus/latest/configuration/configuration/#dockerswarm_sd_config
@@ -42,11 +48,11 @@ func (sdc *SDConfig) GetLabels(baseDir string) ([]map[string]string, error) {
 		return nil, fmt.Errorf("cannot get API config: %w", err)
 	}
 	switch sdc.Role {
-	case "tasks":
+	case roleTasks:
 		return getTasksLabels(cfg)
-	case "services":
+	case roleServices:
 		return getServicesLabels(cfg)
-	case "nodes":
+	case roleNodes:
 		return getNodesLabels(cfg)
 	default:
 		return nil, fmt.Errorf("unexpected `role`: %q; must be one of `tasks`, `services` or `nodes`; skipping it", sdc.Role)

lib/promscrape/discovery/dockerswarm/network.go

@@ -27,7 +27,7 @@ func getNetworksLabelsByNetworkID(cfg *apiConfig) (map[string]map[string]string,
 }
 
 func getNetworks(cfg *apiConfig) ([]network, error) {
-	resp, err := cfg.getAPIResponse("/networks")
+	resp, err := cfg.getAPIResponse("/networks", "")
 	if err != nil {
 		return nil, fmt.Errorf("cannot query dockerswarm api for networks: %w", err)
 	}

lib/promscrape/discovery/dockerswarm/nodes.go

@@ -46,7 +46,12 @@ func getNodesLabels(cfg *apiConfig) ([]map[string]string, error) {
 }
 
 func getNodes(cfg *apiConfig) ([]node, error) {
-	resp, err := cfg.getAPIResponse("/nodes")
+	filtersQueryArg := ""
+	if cfg.role == roleNodes {
+		filtersQueryArg = cfg.filtersQueryArg
+	}
+
+	resp, err := cfg.getAPIResponse("/nodes", filtersQueryArg)
 	if err != nil {
 		return nil, fmt.Errorf("cannot query dockerswarm api for nodes: %w", err)
 	}

lib/promscrape/discovery/dockerswarm/services.go

@@ -59,7 +59,12 @@ func getServicesLabels(cfg *apiConfig) ([]map[string]string, error) {
 }
 
 func getServices(cfg *apiConfig) ([]service, error) {
-	data, err := cfg.getAPIResponse("/services")
+	filtersQueryArg := ""
+	if cfg.role == roleServices {
+		filtersQueryArg = cfg.filtersQueryArg
+	}
+
+	data, err := cfg.getAPIResponse("/services", filtersQueryArg)
 	if err != nil {
 		return nil, fmt.Errorf("cannot query dockerswarm api for services: %w", err)
 	}

lib/promscrape/discovery/dockerswarm/tasks.go

@@ -61,7 +61,12 @@ func getTasksLabels(cfg *apiConfig) ([]map[string]string, error) {
 }
 
 func getTasks(cfg *apiConfig) ([]task, error) {
-	resp, err := cfg.getAPIResponse("/tasks")
+	filtersQueryArg := ""
+	if cfg.role == roleTasks {
+		filtersQueryArg = cfg.filtersQueryArg
+	}
+
+	resp, err := cfg.getAPIResponse("/tasks", filtersQueryArg)
 	if err != nil {
 		return nil, fmt.Errorf("cannot query dockerswarm api for tasks: %w", err)
 	}