Add 'databases' property into YAML configuration - it is used for cla…

…rifying databases from which builtin metrics should be collected. Add database skip logic into functions, tables, indexes, schema collectors.

internal/collector/config.go

@@ -7,6 +7,7 @@ import (
 	"github.com/weaponry/pgscv/internal/log"
 	"github.com/weaponry/pgscv/internal/model"
 	"github.com/weaponry/pgscv/internal/store"
+	"regexp"
 	"strconv"
 	"strings"
 )
@@ -22,6 +23,8 @@ type Config struct {
 	NoTrackMode bool
 	// PostgresServiceConfig defines collector's options specific for Postgres service
 	PostgresServiceConfig
+	// DatabasesRE defines regexp with databases from which builtin metrics should be collected.
+	DatabasesRE *regexp.Regexp
 	// Filters are user-defined regular expressions allow to include/exclude collecting various stats.
 	Filters map[string]filter.Filter
 	// Settings defines collectors settings propagated from main YAML configuration.

internal/collector/postgres_functions.go

@@ -70,6 +70,11 @@ func (c *postgresFunctionsCollector) Update(config Config, ch chan<- prometheus.
 	}
 
 	for _, d := range databases {
+		// Skip database if not matched to allowed.
+		if config.DatabasesRE != nil && !config.DatabasesRE.MatchString(d) {
+			continue
+		}
+
 		pgconfig.Database = d
 		conn, err := store.NewWithConfig(pgconfig)
 		if err != nil {

internal/collector/postgres_indexes.go

@@ -92,6 +92,11 @@ func (c *postgresIndexesCollector) Update(config Config, ch chan<- prometheus.Me
 	}
 
 	for _, d := range databases {
+		// Skip database if not matched to allowed.
+		if config.DatabasesRE != nil && !config.DatabasesRE.MatchString(d) {
+			continue
+		}
+
 		pgconfig.Database = d
 		conn, err := store.NewWithConfig(pgconfig)
 		if err != nil {

internal/collector/postgres_schema.go

@@ -105,6 +105,11 @@ func (c *postgresSchemaCollector) Update(config Config, ch chan<- prometheus.Met
 
 	// walk through all databases, connect to it and collect schema-specific stats
 	for _, d := range databases {
+		// Skip database if not matched to allowed.
+		if config.DatabasesRE != nil && !config.DatabasesRE.MatchString(d) {
+			continue
+		}
+
 		pgconfig.Database = d
 		conn, err := store.NewWithConfig(pgconfig)
 		if err != nil {

internal/collector/postgres_tables.go

@@ -202,6 +202,11 @@ func (c *postgresTablesCollector) Update(config Config, ch chan<- prometheus.Met
 	}
 
 	for _, d := range databases {
+		// Skip database if not matched to allowed.
+		if config.DatabasesRE != nil && !config.DatabasesRE.MatchString(d) {
+			continue
+		}
+
 		pgconfig.Database = d
 		conn, err := store.NewWithConfig(pgconfig)
 		if err != nil {

internal/pgscv/config.go

@@ -39,6 +39,8 @@ type Config struct {
 	Filters               filter.Filters           `yaml:"filters"`
 	DisableCollectors     []string                 `yaml:"disable_collectors"` // List of collectors which should be disabled. DEPRECATED in favor collectors settings
 	CollectorsSettings    model.CollectorsSettings `yaml:"collectors"`         // Collectors settings propagated from main YAML configuration
+	Databases             string                   `yaml:"databases"`          // Regular expression string specifies databases from which metrics should be collected
+	DatabasesRE           *regexp.Regexp           // Regular expression object compiled from Databases
 }
 
 // NewConfig creates new config based on config file or return default config of config is not exists.
@@ -131,6 +133,13 @@ func (c *Config) Validate() error {
 		}
 	}
 
+	// Create 'databases' regexp object for builtin metrics.
+	re, err := newDatabasesRegexp(c.Databases)
+	if err != nil {
+		return err
+	}
+	c.DatabasesRE = re
+
 	// Add default filters and compile regexps.
 	if c.Filters == nil {
 		c.Filters = filter.New()
@@ -226,3 +235,12 @@ func toggleAutoupdate(value string) (string, error) {
 		return "", fmt.Errorf("invalid value '%s' for 'autoupdate'", value)
 	}
 }
+
+// newDatabasesRegexp creates new regexp depending on passed string.
+func newDatabasesRegexp(s string) (*regexp.Regexp, error) {
+	if s == "" {
+		s = ".+"
+	}
+
+	return regexp.Compile(s)
+}

internal/pgscv/config_test.go

@@ -195,6 +195,11 @@ func TestConfig_Validate(t *testing.T) {
 			valid: false,
 			in:    &Config{ListenAddress: "127.0.0.1:8080", Filters: map[string]filter.Filter{"test": {Include: "["}}},
 		},
+		{
+			name:  "invalid config: invalid databases string",
+			valid: false,
+			in:    &Config{ListenAddress: "127.0.0.1:8080", Databases: "["},
+		},
 	}
 
 	for _, tc := range testcases {
@@ -395,3 +400,25 @@ func Test_toggleAutoupdate(t *testing.T) {
 		}
 	}
 }
+
+func Test_newDatabasesRegexp(t *testing.T) {
+	testcases := []struct {
+		valid bool
+		str   string
+	}{
+		{valid: true, str: "example(1|2)"},
+		{valid: true, str: ""},
+		{valid: false, str: "["},
+	}
+
+	for _, tc := range testcases {
+		got, err := newDatabasesRegexp(tc.str)
+		if tc.valid {
+			assert.NoError(t, err)
+			assert.NotNil(t, got)
+		} else {
+			assert.Error(t, err)
+			assert.Nil(t, got)
+		}
+	}
+}

internal/pgscv/pgscv.go

@@ -31,6 +31,7 @@ func Start(ctx context.Context, config *Config) error {
 		ConnDefaults:       config.Defaults,
 		ConnsSettings:      config.ServicesConnsSettings,
 		Filters:            config.Filters,
+		DatabasesRE:        config.DatabasesRE,
 		DisabledCollectors: config.DisableCollectors,
 		CollectorsSettings: config.CollectorsSettings,
 	}

internal/service/service.go

@@ -16,6 +16,7 @@ import (
 	"io"
 	"os"
 	"path/filepath"
+	"regexp"
 	"strconv"
 	"strings"
 	"sync"
@@ -51,11 +52,13 @@ type Service struct {
 
 // Config defines service's configuration.
 type Config struct {
-	RuntimeMode        int
-	NoTrackMode        bool
-	ConnDefaults       map[string]string `yaml:"defaults"` // Defaults
-	ConnsSettings      ConnsSettings
-	Filters            map[string]filter.Filter
+	RuntimeMode   int
+	NoTrackMode   bool
+	ConnDefaults  map[string]string `yaml:"defaults"` // Defaults
+	ConnsSettings ConnsSettings
+	Filters       map[string]filter.Filter
+	// DatabasesRE defines regexp with databases from which builtin metrics should be collected.
+	DatabasesRE        *regexp.Regexp
 	DisabledCollectors []string
 	// CollectorsSettings defines all collector settings propagated from main YAML configuration.
 	CollectorsSettings model.CollectorsSettings
@@ -364,6 +367,7 @@ func (repo *Repository) setupServices(config Config) error {
 				ConnString:  service.ConnSettings.Conninfo,
 				Filters:     config.Filters,
 				Settings:    config.CollectorsSettings,
+				DatabasesRE: config.DatabasesRE,
 			}
 
 			switch service.ConnSettings.ServiceType {