Use environment DialContext and Listen everywhere

TODO.md

@@ -5,7 +5,6 @@
   - Why a factory?
   - First steps after provisioning
 
-- Use `environment.Dial()` and `environment.Listen()`
 - Move `provision_entrypoint.sh` into go
 - Enhance Snapshots
     - Export the Docker Images

cmd/server.go

@@ -32,13 +32,22 @@ var errServerListen = exit.Error{
 }
 
 func (s server) Run(context wisski_distillery.Context) error {
-	handler, err := context.Environment.Dis().Server(context.IOStream)
+	dis := context.Environment
+	handler, err := dis.Control().Server(context.IOStream)
 	if err != nil {
 		return err
 	}
 
 	context.Printf("Listening on %s\n", s.Bind)
-	err = http.ListenAndServe(s.Bind, http.StripPrefix(s.Prefix, handler))
+
+	// make a new listener
+	listener, err := dis.Core.Environment.Listen("tcp", s.Bind)
+	if err != nil {
+		return errServerListen.Wrap(err)
+	}
+
+	// and serve that listener
+	err = http.Serve(listener, http.StripPrefix(s.Prefix, handler))
 	if err == nil {
 		return nil
 	}

cmd/update_prefix_config.go

@@ -38,7 +38,7 @@ func (upc updateprefixconfig) Run(context wisski_distillery.Context) error {
 		return errPrefixUpdateFailed.WithMessageF(err)
 	}
 
-	ddis := dis.Dis()
+	ddis := dis.Control()
 	target := ddis.ResolverConfigPath()
 
 	// print the configuration

go.mod

@@ -7,6 +7,7 @@ require (
 	github.com/Showmax/go-fqdn v1.0.0
 	github.com/alessio/shellescape v1.4.1
 	github.com/feiin/sqlstring v0.3.0
+	github.com/go-sql-driver/mysql v1.6.0
 	github.com/pkg/errors v0.9.1
 	github.com/tkw1536/goprogram v0.0.12
 	golang.org/x/exp v0.0.0-20220909182711-5c715a9e8561
@@ -16,7 +17,6 @@ require (
 )
 
 require (
-	github.com/go-sql-driver/mysql v1.6.0 // indirect
 	github.com/jessevdk/go-flags v1.5.0 // indirect
 	github.com/jinzhu/inflection v1.0.0 // indirect
 	github.com/jinzhu/now v1.1.5 // indirect

internal/component/control/control.go

@@ -9,7 +9,7 @@ import (
 	"github.com/FAU-CDI/wisski-distillery/pkg/environment"
 )
 
-// Control represents the control server
+// Control represents the running control server.
 type Control struct {
 	component.ComponentBase
 

internal/component/sql/database.go

@@ -1,9 +1,14 @@
 package sql
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"io"
+	"net"
+	"sync/atomic"
+
+	mysqldriver "github.com/go-sql-driver/mysql"
 
 	"github.com/FAU-CDI/wisski-distillery/internal/bookkeeping"
 	"github.com/FAU-CDI/wisski-distillery/pkg/logging"
@@ -15,13 +20,29 @@ import (
 	"gorm.io/gorm/logger"
 )
 
+var proxyNameCounter uint64
+
+// registerDialingProxy registers a new custom network protocol with the underlying sql driver.
+// The new protocol will call dialer with the provided network argument.
+// The name of the new protocol is returned.
+func registerDialingProxy(network string, dialer func(context context.Context, network, address string) (net.Conn, error)) (name string) {
+	name = fmt.Sprintf("sql-proxy-%d", atomic.AddUint64(&proxyNameCounter, 1))
+	mysqldriver.RegisterDialContext(name, func(ctx context.Context, addr string) (net.Conn, error) {
+		return dialer(ctx, network, addr)
+	})
+	return
+}
+
 // sqlOpen opens a new sql connection to the provided database using the administrative credentials
-func (sql SQL) openDatabase(database string, config *gorm.Config) (*gorm.DB, error) {
+func (sql *SQL) openDatabase(database string, config *gorm.Config) (*gorm.DB, error) {
+	network := sql.sqlNetwork.Get(func() string {
+		return registerDialingProxy("tcp", sql.Core.Environment.DialContext)
+	})
 	cfg := mysql.Config{
-		DSN:               fmt.Sprintf("%s:%s@tcp(%s)/%s?charset=utf8&parseTime=True&loc=Local", sql.Config.MysqlAdminUser, sql.Config.MysqlAdminPassword, sql.ServerURL, database),
+		DriverName:        "mysql",
+		DSN:               fmt.Sprintf("%s:%s@%s(%s)/%s?charset=utf8&parseTime=True&loc=Local", sql.Config.MysqlAdminUser, sql.Config.MysqlAdminPassword, network, sql.ServerURL, database),
 		DefaultStringSize: 256,
 	}
-	// TODO: Use sql.Core.Environment.Dial
 
 	db, err := gorm.Open(mysql.New(cfg), config)
 	if err != nil {
@@ -38,7 +59,7 @@ func (sql SQL) openDatabase(database string, config *gorm.Config) (*gorm.DB, err
 }
 
 // OpenBookkeeping opens a connection to the bookkeeping database
-func (sql SQL) OpenBookkeeping(silent bool) (*gorm.DB, error) {
+func (sql *SQL) OpenBookkeeping(silent bool) (*gorm.DB, error) {
 
 	config := &gorm.Config{}
 	if silent {
@@ -75,12 +96,12 @@ func (sql SQL) Snapshot(io stream.IOStream, dest io.Writer, database string) err
 }
 
 // OpenShell executes a mysql shell command
-func (sql SQL) OpenShell(io stream.IOStream, argv ...string) (int, error) {
+func (sql *SQL) OpenShell(io stream.IOStream, argv ...string) (int, error) {
 	return sql.Stack(sql.Environment).Exec(io, "sql", "mysql", argv...)
 }
 
 // WaitShell waits for the sql database to be reachable via a docker-compose shell
-func (sql SQL) WaitShell() error {
+func (sql *SQL) WaitShell() error {
 	n := stream.FromNil()
 	return wait.Wait(func() bool {
 		code, err := sql.OpenShell(n, "-e", "show databases;")
@@ -89,7 +110,7 @@ func (sql SQL) WaitShell() error {
 }
 
 // Wait waits for a connection to the bookkeeping table to suceed
-func (sql SQL) Wait() error {
+func (sql *SQL) Wait() error {
 	return wait.Wait(func() bool {
 		_, err := sql.OpenBookkeeping(true)
 		return err == nil
@@ -98,14 +119,14 @@ func (sql SQL) Wait() error {
 
 var errInvalidDatabaseName = errors.New("SQLProvision: Invalid database name")
 
-func (sql SQL) Query(query string, args ...interface{}) bool {
+func (sql *SQL) Query(query string, args ...interface{}) bool {
 	raw := sqle.Format(query, args...)
 	code, err := sql.OpenShell(stream.FromNil(), "-e", raw)
 	return err == nil && code == 0
 }
 
 // SQLProvision provisions a new sql database and user
-func (sql SQL) Provision(name, user, password string) error {
+func (sql *SQL) Provision(name, user, password string) error {
 	// wait for the database
 	if err := sql.WaitShell(); err != nil {
 		return err
@@ -128,7 +149,7 @@ func (sql SQL) Provision(name, user, password string) error {
 var errSQLPurgeUser = errors.New("unable to delete user")
 
 // SQLPurgeUser deletes the specified user from the database
-func (sql SQL) PurgeUser(user string) error {
+func (sql *SQL) PurgeUser(user string) error {
 	if !sql.Query("DROP USER IF EXISTS ?@`%`; FLUSH PRIVILEGES; ", user) {
 		return errSQLPurgeUser
 	}
@@ -139,7 +160,7 @@ func (sql SQL) PurgeUser(user string) error {
 var errSQLPurgeDB = errors.New("unable to drop database")
 
 // SQLPurgeDatabase deletes the specified db from the database
-func (sql SQL) PurgeDatabase(db string) error {
+func (sql *SQL) PurgeDatabase(db string) error {
 	if !sqle.IsSafeDatabaseName(db) {
 		return errSQLPurgeDB
 	}
@@ -154,7 +175,7 @@ var errSQLUnsafeDatabaseName = errors.New("bookkeeping database has an unsafe na
 var errSQLUnableToCreate = errors.New("unable to create bookkeeping database")
 
 // Bootstrap bootstraps the SQL database, and makes sure that the bookkeeping table is up-to-date
-func (sql SQL) Bootstrap(io stream.IOStream) error {
+func (sql *SQL) Bootstrap(io stream.IOStream) error {
 	if err := sql.WaitShell(); err != nil {
 		return err
 	}

internal/component/sql/sql.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/FAU-CDI/wisski-distillery/internal/component"
 	"github.com/FAU-CDI/wisski-distillery/pkg/environment"
+	"github.com/FAU-CDI/wisski-distillery/pkg/lazy"
 )
 
 type SQL struct {
@@ -16,6 +17,8 @@ type SQL struct {
 
 	PollContext  context.Context // context to abort polling with
 	PollInterval time.Duration   // duration to wait for during wait
+
+	sqlNetwork lazy.Lazy[string]
 }
 
 func (SQL) Name() string {
@@ -25,7 +28,7 @@ func (SQL) Name() string {
 //go:embed all:sql
 var resources embed.FS
 
-func (ssh SQL) Stack(env environment.Environment) component.StackWithResources {
+func (ssh *SQL) Stack(env environment.Environment) component.StackWithResources {
 	return ssh.ComponentBase.MakeStack(env, component.StackWithResources{
 		Resources:   resources,
 		ContextPath: "sql",

internal/component/triplestore/database.go

@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"io"
 	"mime/multipart"
-	"net"
 	"net/http"
 
 	"github.com/FAU-CDI/wisski-distillery/pkg/logging"
@@ -64,10 +63,8 @@ func (ts Triplestore) OpenRaw(method, url string, body interface{}, bodyName str
 	// create the request object
 	client := &http.Client{
 		Transport: &http.Transport{
-			Dial: ts.Environment.Dial,
+			DialContext:       ts.Environment.DialContext,
-			DialTLS: func(network, addr string) (net.Conn, error) {
+			DisableKeepAlives: true,
-				return nil, errors.New("not implemented")
-			},
 		},
 	}
 	req, err := http.NewRequest(method, ts.BaseURL+url, reader)

internal/wisski/component.go

@@ -70,7 +70,7 @@ func makeComponent[C component.Component](dis *Distillery, field *lazy.Lazy[C],
 func (dis *Distillery) ComponentsX() []component.Component {
 	return []component.Component{
 		dis.Web(),
-		dis.Dis(),
+		dis.Control(),
 		dis.SSH(),
 		dis.Triplestore(),
 		dis.SQL(),
@@ -107,7 +107,7 @@ func (dis *Distillery) Web() *web.Web {
 	return makeComponent(dis, &dis.components.web, nil)
 }
 
-func (d *Distillery) Dis() *control.Control {
+func (d *Distillery) Control() *control.Control {
 	return makeComponent(d, &d.components.control, func(ddis *control.Control) {
 		ddis.ResolverFile = core.PrefixConfig
 		ddis.Instances = d.Instances()

pkg/environment/environment.go

@@ -1,6 +1,7 @@
 package environment
 
 import (
+	"context"
 	"io"
 	"io/fs"
 	"net"
@@ -41,7 +42,7 @@ type Environment interface {
 	Abs(path string) (string, error)
 
 	Listen(network, address string) (net.Listener, error)
-	Dial(network, address string) (net.Conn, error)
+	DialContext(context context.Context, network, address string) (net.Conn, error)
 
 	Executable() (string, error)
 	Exec(io stream.IOStream, workdir string, exe string, argv ...string) int

pkg/environment/native_net.go

@@ -1,11 +1,15 @@
 package environment
 
-import "net"
+import (
+	"context"
+	"net"
+)
 
 func (Native) Listen(network, address string) (net.Listener, error) {
 	return net.Listen(network, address)
 }
 
-func (Native) Dial(network, address string) (net.Conn, error) {
+func (Native) DialContext(context context.Context, network, address string) (net.Conn, error) {
-	return net.Dial(network, address)
+	var d net.Dialer
+	return d.DialContext(context, network, address)
 }