Update sessions/sessiondb/badger to its latest version and SessionController is able to initialize itself if session manager is not provided by the caller-dev.

Changes:

Update the badger database using transactions, as supported from yesterday via: 06242925c2

Add a custom `OnActivate` via mvc/activator/activate_listener.go, this can be used to perform any custom actions when the app registers the supported Controllers. See mvc/session_controller.go for the excellent use case.

errors.Reporter.AddErr returns true if the error is added to the stack, otherwise false


Former-commit-id: c896a2d186a4315643f3c5fdb4325f7ee48a9e0a

_examples/mvc/session-controller/main.go

@@ -23,7 +23,8 @@ func (u *VisitController) Get() {
 	u.Session.Set("visits", visits)
 
 	// write the current, updated visits
-	u.Ctx.Writef("%d visits in %0.1f seconds", visits, time.Now().Sub(u.StartTime).Seconds())
+	u.Ctx.Writef("%d visit from my current session in %0.1f seconds of server's up-time",
+		visits, time.Now().Sub(u.StartTime).Seconds())
 }
 
 func main() {

core/errors/reporter.go

@@ -56,23 +56,33 @@ func NewReporter() *Reporter {
 // AddErr adds an error to the error stack.
 // if "err" is a StackError then
 // each of these errors will be printed as individual.
-func (r *Reporter) AddErr(err error) {
+//
+// Returns true if this "err" is not nil and it's added to the reporter's stack.
+func (r *Reporter) AddErr(err error) bool {
 	if err == nil {
-		return
+		return false
 	}
 
 	if stackErr, ok := err.(StackError); ok {
 		r.addStack(stackErr.Stack())
-		return
+	} else {
+		r.mu.Lock()
+		r.wrapper = r.wrapper.AppendErr(err)
+		r.mu.Unlock()
 	}
 
-	r.mu.Lock()
-	r.wrapper = r.wrapper.AppendErr(err)
-	r.mu.Unlock()
+	return true
 }
 
 // Add adds a formatted message as an error to the error stack.
-func (r *Reporter) Add(format string, a ...interface{}) {
+//
+// Returns true if this "err" is not nil and it's added to the reporter's stack.
+func (r *Reporter) Add(format string, a ...interface{}) bool {
+
+	if format == "" && len(a) == 0 {
+		return false
+	}
+
 	//  usually used as:  "module: %v", err so
 	// check if the first argument is error and if that error is empty then don't add it.
 	if len(a) > 0 {
@@ -81,7 +91,7 @@ func (r *Reporter) Add(format string, a ...interface{}) {
 			Error() string
 		}); ok {
 			if e.Error() == "" {
-				return
+				return false
 			}
 		}
 	}
@@ -89,6 +99,7 @@ func (r *Reporter) Add(format string, a ...interface{}) {
 	r.mu.Lock()
 	r.wrapper = r.wrapper.Append(format, a...)
 	r.mu.Unlock()
+	return true
 }
 
 // Describe same as `Add` but if "err" is nil then it does nothing.

core/router/api_builder.go

@@ -545,12 +545,6 @@ func (api *APIBuilder) Controller(relativePath string, controller activator.Base
 		api.reporter.Add("%v for path: '%s'", err, relativePath)
 	}
 
-	if cInit, ok := controller.(interface {
-		Init(activator.RegisterFunc)
-	}); ok {
-		cInit.Init(registerFunc)
-	}
-
 	return
 }
 

go19.go

@@ -9,13 +9,6 @@ import (
 	"github.com/kataras/iris/mvc"
 )
 
-// TODO: When go 1.9 will be released
-// split this file in order to separate the concepts.
-//
-// Files should change after go1.9 final release:
-// README.md: Hello World with Go 1.9
-// core/host/supervisor.go
-// context.go
 type (
 	// Context is the midle-man server's "object" for the clients.
 	//

mvc/activator/activate_listener.go

@@ -0,0 +1,78 @@
+package activator
+
+import (
+	"reflect"
+)
+
+// CallOnActivate simply calls the "controller"'s `OnActivate(*ActivatePayload)` function,
+// if any.
+//
+// Look `activator.go#Register` and `ActivateListener` for more.
+func CallOnActivate(controller interface{},
+	bindValues *[]interface{}, registerFunc RegisterFunc) {
+
+	if ac, ok := controller.(ActivateListener); ok {
+		p := &ActivatePayload{
+			BindValues: bindValues,
+			Handle:     registerFunc,
+		}
+		ac.OnActivate(p)
+	}
+}
+
+// ActivateListener is an interface which should be declared
+// on a Controller which needs to register or change the bind values
+// that the caller-"user" has been passed to; via the `app.Controller`.
+// If that interface is completed by a controller
+// then the `OnActivate` function will be called ONCE, NOT in every request
+// but ONCE at the application's lifecycle.
+type ActivateListener interface {
+	// OnActivate accepts a pointer to the `ActivatePayload`.
+	//
+	// The `Controller` can make use of the `OnActivate` function
+	// to register custom routes
+	// or modify the provided values that will be binded to the
+	// controller later on.
+	//
+	// Look `ActivatePayload` for more.
+	OnActivate(*ActivatePayload)
+}
+
+// ActivatePayload contains the necessary information and the ability
+// to alt a controller's registration options, i.e the binder.
+//
+// With `ActivatePayload` the `Controller` can register custom routes
+// or modify the provided values that will be binded to the
+// controller later on.
+type ActivatePayload struct {
+	BindValues *[]interface{}
+	Handle     RegisterFunc
+}
+
+// EnsureBindValue will make sure that this "bindValue"
+// will be registered to the controller's binder
+// if its type is not already passed by the caller..
+//
+// For example, on `SessionController` it looks if *sessions.Sessions
+// has been binded from the caller and if not then the "bindValue"
+// will be binded and used as a default sessions manager instead.
+//
+// At general, if the caller has already provided a value with the same Type
+// then the "bindValue" will be ignored and not be added to the controller's bind values.
+//
+// Returns true if the caller has NOT already provided a value with the same Type
+// and "bindValue" is NOT ignored therefore is appended to the controller's bind values.
+func (i *ActivatePayload) EnsureBindValue(bindValue interface{}) bool {
+	valueTyp := reflect.TypeOf(bindValue)
+	localBindValues := *i.BindValues
+
+	for _, bindedValue := range localBindValues {
+		// type already exists, remember: binding here is per-type.
+		if reflect.TypeOf(bindedValue) == valueTyp {
+			return false
+		}
+	}
+
+	*i.BindValues = append(localBindValues, bindValue)
+	return true
+}

mvc/activator/activator.go

@@ -65,7 +65,6 @@ type BaseController interface {
 
 // ActivateController returns a new controller type info description.
 func ActivateController(base BaseController, bindValues []interface{}) (TController, error) {
-
 	// get and save the type.
 	typ := reflect.TypeOf(base)
 	if typ.Kind() != reflect.Ptr {
@@ -202,6 +201,8 @@ func RegisterMethodHandlers(t TController, registerFunc RegisterFunc) {
 func Register(controller BaseController, bindValues []interface{},
 	registerFunc RegisterFunc) error {
 
+	CallOnActivate(controller, &bindValues, registerFunc)
+
 	t, err := ActivateController(controller, bindValues)
 	if err != nil {
 		return err

mvc/controller_test.go

@@ -7,6 +7,7 @@ import (
 	"github.com/kataras/iris"
 	"github.com/kataras/iris/context"
 	"github.com/kataras/iris/mvc"
+	"github.com/kataras/iris/mvc/activator"
 
 	"github.com/kataras/iris/core/router"
 	"github.com/kataras/iris/httptest"
@@ -493,3 +494,33 @@ func TestControllerRelPathFromFunc(t *testing.T) {
 	e.GET("/anything/here").Expect().Status(httptest.StatusOK).
 		Body().Equal("GET:/anything/here")
 }
+
+type testControllerActivateListener struct {
+	mvc.Controller
+
+	TitlePointer *testBindType
+}
+
+func (c *testControllerActivateListener) OnActivate(p *activator.ActivatePayload) {
+	p.EnsureBindValue(&testBindType{
+		title: "default title",
+	})
+}
+
+func (c *testControllerActivateListener) Get() {
+	c.Text = c.TitlePointer.title
+}
+
+func TestControllerActivateListener(t *testing.T) {
+	app := iris.New()
+	app.Controller("/", new(testControllerActivateListener))
+	app.Controller("/manual", new(testControllerActivateListener), &testBindType{
+		title: "my title",
+	})
+
+	e := httptest.New(t, app)
+	e.GET("/").Expect().Status(httptest.StatusOK).
+		Body().Equal("default title")
+	e.GET("/manual").Expect().Status(httptest.StatusOK).
+		Body().Equal("my title")
+}

mvc/go19.go

@@ -0,0 +1,19 @@
+// +build go1.9
+
+package mvc
+
+import (
+	"github.com/kataras/iris/mvc/activator"
+)
+
+// ActivatePayload contains the necessary information and the ability
+// to alt a controller's registration options, i.e the binder.
+//
+// With `ActivatePayload` the `Controller` can register custom routes
+// or modify the provided values that will be binded to the
+// controller later on.
+//
+// Look the `mvc/activator#ActivatePayload` for its implementation.
+//
+// A shortcut for the `mvc/activator#ActivatePayload`, useful when `OnActivate` is being used.
+type ActivatePayload = activator.ActivatePayload

mvc/session_controller.go

@@ -2,9 +2,14 @@ package mvc
 
 import (
 	"github.com/kataras/iris/context"
+	"github.com/kataras/iris/mvc/activator"
 	"github.com/kataras/iris/sessions"
+
+	"github.com/kataras/golog"
 )
 
+var defaultManager = sessions.New(sessions.Config{})
+
 // SessionController is a simple `Controller` implementation
 // which requires a binded session manager in order to give
 // direct access to the current client's session via its `Session` field.
@@ -15,21 +20,27 @@ type SessionController struct {
 	Session *sessions.Session
 }
 
-var managerMissing = "MVC SessionController: session manager field is nil, you have to bind it to a *sessions.Sessions"
+// OnActivate called, once per application lifecycle NOT request,
+// every single time the dev registers a specific SessionController-based controller.
+// It makes sure that its "Manager" field is filled
+// even if the caller didn't provide any sessions manager via the `app.Controller` function.
+func (s *SessionController) OnActivate(p *activator.ActivatePayload) {
+	if p.EnsureBindValue(defaultManager) {
+		golog.Warnf(`MVC SessionController: couldn't find any "*sessions.Sessions" bindable value to fill the "Manager" field, 
+therefore this controller is using the default sessions manager instead.
+Please refer to the documentation to learn how you can provide the session manager`)
+	}
+}
 
 // BeginRequest calls the Controller's BeginRequest
 // and tries to initialize the current user's Session.
 func (s *SessionController) BeginRequest(ctx context.Context) {
 	s.Controller.BeginRequest(ctx)
 	if s.Manager == nil {
-		ctx.Application().Logger().Errorf(managerMissing)
+		ctx.Application().Logger().Errorf(`MVC SessionController: sessions manager is nil, report this as a bug 
+because the SessionController should predict this on its activation state and use a default one automatically`)
 		return
 	}
 
 	s.Session = s.Manager.Start(ctx)
 }
-
-/* TODO:
-Maybe add struct tags on `binder` for required binded values
-in order to log error if some of the bindings are missing or leave that to the end-developers?
-*/

sessions/sessiondb/badger/database.go

@@ -22,7 +22,7 @@ type Database struct {
 	// Service is the underline badger database connection,
 	// it's initialized at `New` or `NewFromDB`.
 	// Can be used to get stats.
-	Service *badger.KV
+	Service *badger.DB
 	async   bool
 }
 
@@ -51,7 +51,7 @@ func New(directoryPath string) (*Database, error) {
 	opts.Dir = directoryPath
 	opts.ValueDir = directoryPath
 
-	service, err := badger.NewKV(&opts)
+	service, err := badger.Open(&opts)
 
 	if err != nil {
 		golog.Errorf("unable to initialize the badger-based session database: %v", err)
@@ -62,7 +62,7 @@ func New(directoryPath string) (*Database, error) {
 }
 
 // NewFromDB same as `New` but accepts an already-created custom badger connection instead.
-func NewFromDB(service *badger.KV) (*Database, error) {
+func NewFromDB(service *badger.DB) (*Database, error) {
 	if service == nil {
 		return nil, errors.New("underline database is missing")
 	}
@@ -75,30 +75,37 @@ func NewFromDB(service *badger.KV) (*Database, error) {
 
 // Cleanup removes any invalid(have expired) session entries,
 // it's being called automatically on `New` as well.
-func (db *Database) Cleanup() error {
+func (db *Database) Cleanup() (err error) {
 	rep := errors.NewReporter()
 
-	iter := db.Service.NewIterator(badger.DefaultIteratorOptions)
+	txn := db.Service.NewTransaction(true)
+	defer txn.Commit(nil)
+
+	iter := txn.NewIterator(badger.DefaultIteratorOptions)
+	defer iter.Close()
+
 	for iter.Rewind(); iter.Valid(); iter.Next() {
 		// Remember that the contents of the returned slice should not be modified, and
 		// only valid until the next call to Next.
 		item := iter.Item()
-		err := item.Value(func(b []byte) error {
-			storeDB, err := sessions.DecodeRemoteStore(b)
-			if err != nil {
-				return err
-			}
+		b, err := item.Value()
 
-			if storeDB.Lifetime.HasExpired() {
-				err = db.Service.Delete(item.Key())
-			}
-			return err
-		})
+		if rep.AddErr(err) {
+			continue
+		}
 
-		rep.AddErr(err)
+		storeDB, err := sessions.DecodeRemoteStore(b)
+		if rep.AddErr(err) {
+			continue
+		}
+
+		if storeDB.Lifetime.HasExpired() {
+			if err := txn.Delete(item.Key()); err != nil {
+				rep.AddErr(err)
+			}
+		}
 	}
 
-	iter.Close()
 	return rep.Return()
 }
 
@@ -112,21 +119,28 @@ func (db *Database) Async(useGoRoutines bool) *Database {
 // Load loads the sessions from the badger(key-value file-based) session storage.
 func (db *Database) Load(sid string) (storeDB sessions.RemoteStore) {
 	bsid := []byte(sid)
-	iter := db.Service.NewIterator(badger.DefaultIteratorOptions)
-	defer iter.Close()
 
-	iter.Seek(bsid)
-	if !iter.Valid() {
+	txn := db.Service.NewTransaction(false)
+	defer txn.Discard()
+
+	item, err := txn.Get(bsid)
+	if err != nil {
+		// Key not found, don't report this, session manager will create a new session as it should.
 		return
 	}
-	item := iter.Item()
-	item.Value(func(b []byte) (err error) {
-		storeDB, err = sessions.DecodeRemoteStore(b) // decode the whole value, as a remote store
-		if err != nil {
-			golog.Errorf("error while trying to load from the remote store: %v", err)
-		}
+
+	b, err := item.Value()
+
+	if err != nil {
+		golog.Errorf("error while trying to get the serialized session(%s) from the remote store: %v", sid, err)
 		return
-	})
+	}
+
+	storeDB, err = sessions.DecodeRemoteStore(b) // decode the whole value, as a remote store
+	if err != nil {
+		golog.Errorf("error while trying to load from the remote store: %v", err)
+	}
+
 	return
 }
 
@@ -155,19 +169,28 @@ func (db *Database) sync(p sessions.SyncPayload) {
 		golog.Errorf("error while serializing the remote store: %v", err)
 	}
 
-	// err = db.Service.Set(bsid, s, meta)
-	e := &badger.Entry{
-		Key:   bsid,
-		Value: s,
-	}
-	err = db.Service.BatchSet([]*badger.Entry{e})
+	txn := db.Service.NewTransaction(true)
+
+	err = txn.Set(bsid, s, 0x00)
 	if err != nil {
-		golog.Errorf("error while writing the session(%s) to the database: %v", p.SessionID, err)
+		txn.Discard()
+		golog.Errorf("error while trying to save the session(%s) to the database: %v", p.SessionID, err)
+		return
+	}
+	if err := txn.Commit(nil); err != nil { // Commit will call the Discard automatically.
+		golog.Errorf("error while committing the session(%s) changes to the database: %v", p.SessionID, err)
 	}
 }
 
 func (db *Database) destroy(bsid []byte) error {
-	return db.Service.Delete(bsid)
+	txn := db.Service.NewTransaction(true)
+
+	err := txn.Delete(bsid)
+	if err != nil {
+		return err
+	}
+
+	return txn.Commit(nil)
 }
 
 // Close shutdowns the badger connection.