Create a global set of provider instances (namespaced by app name) to…

… track their lifecyeles, thus removing this responsibility from the individual drivers.

cmd/internal/register/maps_test.go

@@ -29,7 +29,7 @@ func TestMaps(t *testing.T) {
 				provArr[i] = tc.providers[i]
 			}
 
-			providers, err := register.Providers(provArr, tc.maps)
+			providers, err := register.Providers(provArr, tc.maps, "default")
 			if err != nil {
 				t.Errorf("unexpected err: %v", err)
 				return

cmd/internal/register/providers.go

@@ -33,7 +33,7 @@ func (e ErrProviderTypeInvalid) Error() string {
 }
 
 // Providers registers data provider backends
-func Providers(providers []dict.Dicter, maps []provider.Map) (map[string]provider.TilerUnion, error) {
+func Providers(providers []dict.Dicter, maps []provider.Map, namespace string) (map[string]provider.TilerUnion, error) {
 	// holder for registered providers
 	registeredProviders := map[string]provider.TilerUnion{}
 
@@ -72,7 +72,7 @@ func Providers(providers []dict.Dicter, maps []provider.Map) (map[string]provide
 		}
 
 		// register the provider
-		prov, err := provider.For(ptype, p, maps)
+		prov, err := provider.For(ptype, p, maps, namespace)
 		if err != nil {
 			return registeredProviders, err
 		}
@@ -84,3 +84,12 @@ func Providers(providers []dict.Dicter, maps []provider.Map) (map[string]provide
 
 	return registeredProviders, nil
 }
+
+func UnloadProviders(names []string, namespace string) {
+	for _, name := range names {
+		err := provider.Remove(name, namespace)
+		if err != nil {
+			log.Errorf("Error unloading provider instance %s: %s", name, err)
+		}
+	}
+}

cmd/internal/register/providers_test.go

@@ -23,7 +23,7 @@ func TestProviders(t *testing.T) {
 				provArr[i] = tc.config[i]
 			}
 
-			_, err = register.Providers(provArr, nil)
+			_, err = register.Providers(provArr, nil, "default")
 			if tc.expectedErr != nil {
 				if err.Error() != tc.expectedErr.Error() {
 					t.Errorf("invalid error. expected: %v, got %v", tc.expectedErr, err.Error())

cmd/tegola/cmd/root.go

@@ -119,7 +119,7 @@ func initConfig(configFile string, cacheRequired bool, logLevel string, logger s
 	}
 
 	// Init providers from the primary config file.
-	providers, err := initProviders(conf.Providers, conf.Maps)
+	providers, err := initProviders(conf.Providers, conf.Maps, "default")
 	if err != nil {
 		return err
 	}
@@ -159,14 +159,14 @@ func initConfig(configFile string, cacheRequired bool, logLevel string, logger s
 }
 
 // initProviders translate provider config from a TOML file into usable Provider objects.
-func initProviders(providersConfig []env.Dict, maps []provider.Map) (map[string]provider.TilerUnion, error) {
+func initProviders(providersConfig []env.Dict, maps []provider.Map, namespace string) (map[string]provider.TilerUnion, error) {
 	// first convert []env.Map -> []dict.Dicter
 	provArr := make([]dict.Dicter, len(providersConfig))
 	for i := range provArr {
 		provArr[i] = providersConfig[i]
 	}
 
-	providers, err := register.Providers(provArr, conf.Maps)
+	providers, err := register.Providers(provArr, conf.Maps, namespace)
 	if err != nil {
 		return nil, fmt.Errorf("could not register providers: %v", err)
 	}
@@ -229,15 +229,15 @@ func watchAppUpdates(ctx context.Context, watcher source.ConfigWatcher) {
 			// If the new app is named the same as an existing app, first unload the existing one.
 			if old, exists := apps[app.Key]; exists {
 				log.Infof("Unloading app %s...", old.Key)
-				// We need only unload maps, since the providers don't live outside of maps.
 				register.UnloadMaps(nil, getMapNames(old))
-				delete(apps, app.Key)
+				register.UnloadProviders(getProviderNames(old), old.Key)
+				delete(apps, old.Key)
 			}
 
 			log.Infof("Loading app %s...", app.Key)
 
 			// Init new providers
-			providers, err := initProviders(app.Providers, app.Maps)
+			providers, err := initProviders(app.Providers, app.Maps, app.Key)
 			if err != nil {
 				log.Errorf("Failed initializing providers from %s: %s", app.Key, err)
 				continue
@@ -261,6 +261,7 @@ func watchAppUpdates(ctx context.Context, watcher source.ConfigWatcher) {
 			if app, exists := apps[deleted]; exists {
 				log.Infof("Unloading app %s...", app.Key)
 				register.UnloadMaps(nil, getMapNames(app))
+				register.UnloadProviders(getProviderNames(app), app.Key)
 				delete(apps, app.Key)
 			} else {
 				log.Infof("Received an unload event for app %s, but couldn't find it.", deleted)
@@ -280,3 +281,17 @@ func getMapNames(app source.App) []string {
 
 	return names
 }
+
+func getProviderNames(app source.App) []string {
+	names := make([]string, 0, len(app.Providers))
+	for _, p := range app.Providers {
+		name, err := p.String("name", nil)
+		if err != nil {
+			log.Warnf("Encountered a provider in app %s with an empty name.", app.Key)
+			continue
+		}
+		names = append(names, name)
+	}
+
+	return names
+}

cmd/tegola_lambda/main.go

@@ -66,7 +66,7 @@ func init() {
 	}
 
 	// register the providers
-	providers, err := register.Providers(provArr, nil)
+	providers, err := register.Providers(provArr, nil, "default")
 	if err != nil {
 		log.Fatal(err)
 	}

provider/debug/debug.go

@@ -22,7 +22,7 @@ const (
 )
 
 func init() {
-	provider.Register(provider.TypeStd.Prefix()+Name, NewTileProvider, nil)
+	provider.Register(provider.TypeStd.Prefix()+Name, NewTileProvider)
 }
 
 // NewProvider Setups a debug provider. there are not currently any config params supported
@@ -113,3 +113,8 @@ func (p *Provider) Layers() ([]provider.LayerInfo, error) {
 
 	return ls, nil
 }
+
+// Cleanup is a no-op for the debug provider.
+func (p *Provider) Cleanup() error {
+	return nil
+}

provider/gpkg/gpkg.go

@@ -235,6 +235,11 @@ func (p *Provider) Close() error {
 	return p.db.Close()
 }
 
+// Cleanup calls Close()
+func (p *Provider) Cleanup() error {
+	return p.Close()
+}
+
 type GeomTableDetails struct {
 	geomFieldname string
 	geomType      geom.Geometry

provider/gpkg/gpkg_register.go

@@ -26,7 +26,7 @@ import (
 var colFinder *regexp.Regexp
 
 func init() {
-	provider.Register(provider.TypeStd.Prefix()+Name, NewTileProvider, Cleanup)
+	provider.Register(provider.TypeStd.Prefix()+Name, NewTileProvider)
 	colFinder = regexp.MustCompile(`^(([a-zA-Z_][a-zA-Z0-9_]*)|"([^"]+)")\s`)
 }
 
@@ -41,7 +41,8 @@ type featureTableDetails struct {
 }
 
 // Creates a config instance of the type NewTileProvider() requires including all available feature
-//    tables in the gpkg at 'gpkgPath'.
+//
+//	tables in the gpkg at 'gpkgPath'.
 func AutoConfig(gpkgPath string) (map[string]interface{}, error) {
 	// Get all feature tables
 	db, err := sql.Open("sqlite3", gpkgPath)
@@ -394,26 +395,5 @@ func NewTileProvider(config dict.Dicter, maps []provider.Map) (provider.Tiler, e
 		p.layers[layer.name] = layer
 	}
 
-	// track the provider so we can clean it up later
-	providers = append(providers, p)
-
 	return &p, err
 }
-
-// reference to all instantiated providers
-var providers []Provider
-
-// Cleanup will close all database connections and destroy all previously instantiated Provider instances
-func Cleanup() {
-	if len(providers) > 0 {
-		log.Infof("cleaning up gpkg providers")
-	}
-
-	for i := range providers {
-		if err := providers[i].Close(); err != nil {
-			log.Errorf("err closing connection: %v", err)
-		}
-	}
-
-	providers = make([]Provider, 0)
-}

provider/gpkg/gpkg_register_internal_test.go

@@ -11,7 +11,6 @@ import (
 
 	"github.com/go-spatial/geom"
 	"github.com/go-spatial/geom/cmp"
-	"github.com/go-spatial/tegola/dict"
 
 	_ "github.com/mattn/go-sqlite3"
 )
@@ -1088,48 +1087,3 @@ func TestFeatureTableMetaData(t *testing.T) {
 		t.Run(tname, fn(tc))
 	}
 }
-
-func TestCleanup(t *testing.T) {
-	type tcase struct {
-		config dict.Dict
-	}
-
-	fn := func(tc tcase) func(*testing.T) {
-		return func(t *testing.T) {
-			_, err := NewTileProvider(tc.config, nil)
-			if err != nil {
-				t.Fatalf("err creating NewTileProvider: %v", err)
-				return
-			}
-
-			if len(providers) != 1 {
-				t.Errorf("expecting 1 providers, got %v", len(providers))
-				return
-			}
-
-			Cleanup()
-
-			if len(providers) != 0 {
-				t.Errorf("expecting 0 providers, got %v", len(providers))
-				return
-			}
-		}
-	}
-
-	tests := map[string]tcase{
-		"cleanup": {
-			config: map[string]interface{}{
-				"filepath": GPKGAthensFilePath,
-				"layers": []map[string]interface{}{
-					{"name": "a_points", "tablename": "amenities_points", "id_fieldname": "fid", "fields": []string{"amenity", "religion", "tourism", "shop"}},
-					{"name": "r_lines", "tablename": "rail_lines", "id_fieldname": "fid", "fields": []string{"railway", "bridge", "tunnel"}},
-					{"name": "rd_lines", "tablename": "roads_lines"},
-				},
-			},
-		},
-	}
-
-	for name, tc := range tests {
-		t.Run(name, fn(tc))
-	}
-}

provider/hana/hana.go

@@ -597,9 +597,6 @@ func CreateProvider(config dict.Dicter, maps []provider.Map, providerType string
 	}
 	p.layers = lyrs
 
-	// track the provider so we can clean it up later
-	providers = append(providers, p)
-
 	return &p, nil
 }
 
@@ -956,21 +953,11 @@ func (p Provider) MVTForLayers(ctx context.Context, tile provider.Tile, params p
 	return mvtBytes.Bytes(), nil
 }
 
+// Cleanup calls Close()
+func (p *Provider) Cleanup() error {
+	p.Close()
+	return nil
+}
+
 // Close will close the Provider's database connectio
 func (p *Provider) Close() { p.pool.Close() }
-
-// reference to all instantiated providers
-var providers []Provider
-
-// Cleanup will close all database connections and destroy all previously instantiated Provider instances
-func Cleanup() {
-	if len(providers) > 0 {
-		log.Infof("cleaning up HANA providers")
-	}
-
-	for i := range providers {
-		providers[i].Close()
-	}
-
-	providers = make([]Provider, 0)
-}

provider/hana/register.go

@@ -6,8 +6,8 @@ import (
 )
 
 func init() {
-	provider.Register(provider.TypeStd.Prefix()+Name, NewTileProvider, Cleanup)
-	provider.MVTRegister(provider.TypeMvt.Prefix()+Name, NewMVTTileProvider, Cleanup)
+	provider.Register(provider.TypeStd.Prefix()+Name, NewTileProvider)
+	provider.MVTRegister(provider.TypeMvt.Prefix()+Name, NewMVTTileProvider)
 }
 
 const (
@@ -20,23 +20,22 @@ const (
 // trying to create a driver. This Provider supports the following fields
 // in the provided map[string]interface{} map:
 //
-// 	uri (string): [Required] HANA connection string
-// 	name (string): [Required] Provider name is referenced from map layers
-// 	srid (int): [Optional] The default SRID for the provider. Defaults to WebMercator (3857) but also supports WGS84 (4326)
-// 	type (string): [Required] The type of data provider. must be "hana" to use this data provider
-// 	layers (map[string]struct{})  — This is map of layers keyed by the layer name. Supports the following properties
+//	uri (string): [Required] HANA connection string
+//	name (string): [Required] Provider name is referenced from map layers
+//	srid (int): [Optional] The default SRID for the provider. Defaults to WebMercator (3857) but also supports WGS84 (4326)
+//	type (string): [Required] The type of data provider. must be "hana" to use this data provider
+//	layers (map[string]struct{})  — This is map of layers keyed by the layer name. Supports the following properties
 //
-// 		name (string): [Required] the name of the layer. This is used to reference this layer from map layers.
-// 		tablename (string): [*Required] the name of the database table to query against. Required if sql is not defined.
-// 		geometry_fieldname (string): [Optional] the name of the filed which contains the geometry for the feature. defaults to geom
-// 		id_fieldname (string): [Optional] the name of the feature id field. defaults to gid
-// 		fields ([]string): [Optional] a list of fields to include alongside the feature. Can be used if sql is not defined.
-// 		srid (int): [Optional] the SRID of the layer. Supports 3857 (WebMercator) or 4326 (WGS84).
-// 		sql (string): [*Required] custom SQL to use use. Required if tablename is not defined. Supports the following tokens:
-//
-// 			!BBOX! - [Required] will be replaced with the bounding box of the tile before the query is sent to the database.
-// 			!ZOOM! - [Optional] will be replaced with the "Z" (zoom) value of the requested tile.
+//		name (string): [Required] the name of the layer. This is used to reference this layer from map layers.
+//		tablename (string): [*Required] the name of the database table to query against. Required if sql is not defined.
+//		geometry_fieldname (string): [Optional] the name of the filed which contains the geometry for the feature. defaults to geom
+//		id_fieldname (string): [Optional] the name of the feature id field. defaults to gid
+//		fields ([]string): [Optional] a list of fields to include alongside the feature. Can be used if sql is not defined.
+//		srid (int): [Optional] the SRID of the layer. Supports 3857 (WebMercator) or 4326 (WGS84).
+//		sql (string): [*Required] custom SQL to use use. Required if tablename is not defined. Supports the following tokens:
 //
+//			!BBOX! - [Required] will be replaced with the bounding box of the tile before the query is sent to the database.
+//			!ZOOM! - [Optional] will be replaced with the "Z" (zoom) value of the requested tile.
 func NewTileProvider(config dict.Dicter, maps []provider.Map) (provider.Tiler, error) {
 	return CreateProvider(config, maps, ProviderType)
 }

provider/mvt_provider.go

@@ -11,6 +11,9 @@ type MVTTiler interface {
 
 	// MVTForLayers will return a MVT byte array or an error for the given layer names.
 	MVTForLayers(ctx context.Context, tile Tile, params Params, layers []Layer) ([]byte, error)
+
+	// Cleanup will do anything needed before the Tiler is removed.
+	Cleanup() error
 }
 
 // MVTInitFunc initialize a provider given a config map. The init function should validate the config map, and report any errors. This is called by the For function.

provider/postgis/postgis.go

@@ -640,9 +640,6 @@ func CreateProvider(config dict.Dicter, maps []provider.Map, providerType string
 	}
 	p.layers = lyrs
 
-	// track the provider so we can clean it up later
-	providers = append(providers, p)
-
 	return &p, nil
 }
 
@@ -1067,21 +1064,11 @@ func (p Provider) MVTForLayers(ctx context.Context, tile provider.Tile, params p
 	return data.Bytes, nil
 }
 
+// Cleanup calls Close()
+func (p *Provider) Cleanup() error {
+	p.Close()
+	return nil
+}
+
 // Close will close the Provider's database connectio
 func (p *Provider) Close() { p.pool.Close() }
-
-// reference to all instantiated providers
-var providers []Provider
-
-// Cleanup will close all database connections and destroy all previously instantiated Provider instances
-func Cleanup() {
-	if len(providers) > 0 {
-		log.Infof("cleaning up postgis providers")
-	}
-
-	for i := range providers {
-		providers[i].Close()
-	}
-
-	providers = make([]Provider, 0)
-}