Prepare multiplexing support for database plugins (#16995)

* prepare multiplexing support for database plugins

changelog/16995.txt

@@ -0,0 +1,3 @@
+```release-note:improvement
+plugins/multiplexing: Added multiplexing support to database plugins if run as external plugins
+```

plugins/database/cassandra/cassandra-database-plugin/main.go

@@ -5,7 +5,7 @@ import (
 	"os"
 
 	"github.com/hashicorp/vault/plugins/database/cassandra"
-	dbplugin "github.com/hashicorp/vault/sdk/database/dbplugin/v5"
+	"github.com/hashicorp/vault/sdk/database/dbplugin/v5"
 )
 
 func main() {
@@ -18,12 +18,7 @@ func main() {
 
 // Run instantiates a Cassandra object, and runs the RPC server for the plugin
 func Run() error {
-	dbType, err := cassandra.New()
-	if err != nil {
-		return err
-	}
-
-	dbplugin.Serve(dbType.(dbplugin.Database))
+	dbplugin.ServeMultiplex(cassandra.New)
 
 	return nil
 }

plugins/database/hana/hana-database-plugin/main.go

@@ -5,7 +5,7 @@ import (
 	"os"
 
 	"github.com/hashicorp/vault/plugins/database/hana"
-	dbplugin "github.com/hashicorp/vault/sdk/database/dbplugin/v5"
+	"github.com/hashicorp/vault/sdk/database/dbplugin/v5"
 )
 
 func main() {
@@ -18,12 +18,7 @@ func main() {
 
 // Run instantiates a HANA object, and runs the RPC server for the plugin
 func Run() error {
-	dbType, err := hana.New()
-	if err != nil {
-		return err
-	}
-
-	dbplugin.Serve(dbType.(dbplugin.Database))
+	dbplugin.ServeMultiplex(hana.New)
 
 	return nil
 }

plugins/database/influxdb/influxdb-database-plugin/main.go

@@ -5,7 +5,7 @@ import (
 	"os"
 
 	"github.com/hashicorp/vault/plugins/database/influxdb"
-	dbplugin "github.com/hashicorp/vault/sdk/database/dbplugin/v5"
+	"github.com/hashicorp/vault/sdk/database/dbplugin/v5"
 )
 
 func main() {
@@ -18,12 +18,7 @@ func main() {
 
 // Run instantiates a Influxdb object, and runs the RPC server for the plugin
 func Run() error {
-	dbType, err := influxdb.New()
-	if err != nil {
-		return err
-	}
-
-	dbplugin.Serve(dbType.(dbplugin.Database))
+	dbplugin.ServeMultiplex(influxdb.New)
 
 	return nil
 }

plugins/database/mongodb/mongodb-database-plugin/main.go

@@ -5,7 +5,7 @@ import (
 	"os"
 
 	"github.com/hashicorp/vault/plugins/database/mongodb"
-	dbplugin "github.com/hashicorp/vault/sdk/database/dbplugin/v5"
+	"github.com/hashicorp/vault/sdk/database/dbplugin/v5"
 )
 
 func main() {
@@ -18,12 +18,7 @@ func main() {
 
 // Run instantiates a MongoDB object, and runs the RPC server for the plugin
 func Run() error {
-	dbType, err := mongodb.New()
-	if err != nil {
-		return err
-	}
-
-	dbplugin.Serve(dbType.(dbplugin.Database))
+	dbplugin.ServeMultiplex(mongodb.New)
 
 	return nil
 }

plugins/database/mssql/mssql-database-plugin/main.go

@@ -5,7 +5,7 @@ import (
 	"os"
 
 	"github.com/hashicorp/vault/plugins/database/mssql"
-	dbplugin "github.com/hashicorp/vault/sdk/database/dbplugin/v5"
+	"github.com/hashicorp/vault/sdk/database/dbplugin/v5"
 )
 
 func main() {
@@ -18,12 +18,7 @@ func main() {
 
 // Run instantiates a MSSQL object, and runs the RPC server for the plugin
 func Run() error {
-	dbType, err := mssql.New()
-	if err != nil {
-		return err
-	}
-
-	dbplugin.Serve(dbType.(dbplugin.Database))
+	dbplugin.ServeMultiplex(mssql.New)
 
 	return nil
 }

plugins/database/mysql/mysql-database-plugin/main.go

@@ -5,7 +5,7 @@ import (
 	"os"
 
 	"github.com/hashicorp/vault/plugins/database/mysql"
-	dbplugin "github.com/hashicorp/vault/sdk/database/dbplugin/v5"
+	"github.com/hashicorp/vault/sdk/database/dbplugin/v5"
 )
 
 func main() {
@@ -20,12 +20,8 @@ func main() {
 func Run() error {
 	var f func() (interface{}, error)
 	f = mysql.New(mysql.DefaultUserNameTemplate)
-	dbType, err := f()
-	if err != nil {
-		return err
-	}
 
-	dbplugin.Serve(dbType.(dbplugin.Database))
+	dbplugin.ServeMultiplex(f)
 
 	return nil
 }

plugins/database/postgresql/postgresql-database-plugin/main.go

@@ -5,7 +5,7 @@ import (
 	"os"
 
 	"github.com/hashicorp/vault/plugins/database/postgresql"
-	dbplugin "github.com/hashicorp/vault/sdk/database/dbplugin/v5"
+	"github.com/hashicorp/vault/sdk/database/dbplugin/v5"
 )
 
 func main() {
@@ -18,12 +18,7 @@ func main() {
 
 // Run instantiates a PostgreSQL object, and runs the RPC server for the plugin
 func Run() error {
-	dbType, err := postgresql.New()
-	if err != nil {
-		return err
-	}
-
-	dbplugin.Serve(dbType.(dbplugin.Database))
+	dbplugin.ServeMultiplex(postgresql.New)
 
 	return nil
 }

plugins/database/redshift/redshift-database-plugin/main.go

@@ -4,30 +4,20 @@ import (
 	"log"
 	"os"
 
-	"github.com/hashicorp/vault/api"
 	"github.com/hashicorp/vault/plugins/database/redshift"
-	"github.com/hashicorp/vault/sdk/database/dbplugin"
+	"github.com/hashicorp/vault/sdk/database/dbplugin/v5"
 )
 
 func main() {
-	apiClientMeta := &api.PluginAPIClientMeta{}
-	flags := apiClientMeta.FlagSet()
-	flags.Parse(os.Args[1:])
-
-	if err := Run(apiClientMeta.GetTLSConfig()); err != nil {
+	if err := Run(); err != nil {
 		log.Println(err)
 		os.Exit(1)
 	}
 }
 
 // Run instantiates a RedShift object, and runs the RPC server for the plugin
-func Run(apiTLSConfig *api.TLSConfig) error {
-	dbType, err := redshift.New()
-	if err != nil {
-		return err
-	}
-
-	dbplugin.Serve(dbType.(dbplugin.Database), api.VaultPluginTLSProvider(apiTLSConfig))
+func Run() error {
+	dbplugin.ServeMultiplex(redshift.New)
 
 	return nil
 }