ISM ISM ISM ISM ISM

main.go

@@ -1,11 +1,11 @@
 package library
 
 import (
+	"database/sql"
 	"errors"
 	"github.com/go-chi/chi/v5"
 	"github.com/google/uuid"
 	"io/fs"
-	"math/big"
 	"sync"
 	"time"
 )
@@ -42,17 +42,30 @@ type InterServiceMessage struct {
 
 // NewServiceInitializationInformation creates a new ServiceInitializationInformation and is only ever meant to be called
 // by fulgens or a compliant implementation of fulgens.
-func NewServiceInitializationInformation(domain *string, outbox chan<- InterServiceMessage, inbox <-chan InterServiceMessage, router *chi.Mux, configuration map[string]interface{}, resourceDir fs.FS) ServiceInitializationInformation {
-	return ServiceInitializationInformation{
+func NewServiceInitializationInformation(domain *string, outbox chan<- InterServiceMessage, inbox <-chan InterServiceMessage, router *chi.Mux, configuration map[string]interface{}, resourceDir fs.FS) *ServiceInitializationInformation {
+	return &ServiceInitializationInformation{
 		Domain:        domain,
 		Outbox:        outbox,
 		inbox:         inbox,
 		Router:        router,
 		Configuration: configuration,
 		ResourceDir:   resourceDir,
+		internal: internal{
+			buffer:      make(map[uuid.UUID]InterServiceMessage),
+			waitingList: make(map[uuid.UUID]struct{}),
+			arrived:     make(chan uuid.UUID),
+		},
 	}
 }
 
+type internal struct {
+	buffer      map[uuid.UUID]InterServiceMessage
+	waitingList map[uuid.UUID]struct{}
+	mutex       sync.Mutex
+	arrived     chan uuid.UUID
+	ispStarted  bool
+}
+
 type ServiceInitializationInformation struct {
 	Service       *Service `validate:"required"`
 	Domain        *string
@@ -61,6 +74,7 @@ type ServiceInitializationInformation struct {
 	Router        *chi.Mux
 	Configuration map[string]interface{}
 	ResourceDir   fs.FS
+	internal      internal
 }
 
 // YesIAbsolutelyKnowWhatIAmDoingAndIWantToAccessTheRawInbox returns a channel that can be used to read messages from
@@ -72,55 +86,17 @@ func (s *ServiceInitializationInformation) YesIAbsolutelyKnowWhatIAmDoingAndIWan
 	return s.inbox
 }
 
-type ColumnType interface{}
+type DBType int
 
-type (
-	// String represents arbitrary sized text
-	String string
-	// Int32 represents a 32-bit signed integer
-	Int32 int32
-	// Int64 represents a 64-bit signed integer
-	Int64 int64
-	// IntInf represents an arbitrary sized signed integer
-	IntInf big.Int
-	// Float32 represents a 32-bit floating point number
-	Float32 float32
-	// Float64 represents a 64-bit floating point number
-	Float64 float64
-	// Boolean represents a boolean value
-	Boolean bool
-	// Blob represents an arbitrary sized binary object
-	Blob []byte
-	// UUID represents a UUID value
-	UUID uuid.UUID
-	// Time represents a time value
-	Time time.Time
+const (
+	Sqlite DBType = iota
+	Postgres
 )
 
-type TableSchema map[string]ColumnType
-type Row map[string]any
-type Rows []Row
-
-type QueryParameters struct {
-	Equal              map[string]any
-	NotEqual           map[string]any
-	GreaterThan        map[string]any
-	LessThan           map[string]any
-	GreaterThanOrEqual map[string]any
-	LessThanOrEqual    map[string]any
+type Database struct {
+	DB     *sql.DB
+	DBType DBType
 }
-
-type UpdateParameters map[string]any
-
-type Database interface {
-	CreateTable(name string, schema TableSchema) error
-	DeleteTable(name string) error
-	InsertRow(name string, row Row) error
-	Delete(name string, params QueryParameters) error
-	Select(name string, params QueryParameters) (Rows, error)
-	Update(name string, params QueryParameters, update UpdateParameters) error
-}
-
 type MessageCode int
 
 const (
@@ -130,24 +106,19 @@ const (
 	Unauthorized
 )
 
-var buffer = make(map[uuid.UUID]InterServiceMessage)
-var mutex = sync.Mutex{}
-var arrived = make(chan uuid.UUID)
-var ispStarted = false
-
 func (s *ServiceInitializationInformation) StartISProcessor() {
-	if ispStarted {
+	if s.internal.ispStarted {
 		return
 	} else {
-		ispStarted = true
+		s.internal.ispStarted = true
 	}
 	listener := NewListener(s.inbox)
 	for {
 		msg := listener.AcceptMessage()
-		mutex.Lock()
-		buffer[msg.MessageID] = msg
-		mutex.Unlock()
-		arrived <- msg.MessageID
+		s.internal.mutex.Lock()
+		s.internal.buffer[msg.MessageID] = msg
+		s.internal.mutex.Unlock()
+		s.internal.arrived <- msg.MessageID
 	}
 }
 
@@ -155,17 +126,18 @@ var (
 	ErrTimeout = errors.New("timeout")
 )
 
-func AwaitISMessage(id uuid.UUID, timeout time.Duration) (InterServiceMessage, error) {
+func (s *ServiceInitializationInformation) AwaitISMessage(id uuid.UUID, timeout time.Duration) (InterServiceMessage, error) {
 	for {
 		select {
 		case <-time.After(timeout):
 			return InterServiceMessage{}, ErrTimeout
-		case msgID := <-arrived:
+		case msgID := <-s.internal.arrived:
 			if msgID == id {
-				mutex.Lock()
-				msg := buffer[id]
-				delete(buffer, id)
-				mutex.Unlock()
+				s.internal.mutex.Lock()
+				msg := s.internal.buffer[id]
+				delete(s.internal.buffer, id)
+				delete(s.internal.waitingList, id)
+				s.internal.mutex.Unlock()
 				if msg.MessageType != Success {
 					return msg, msg.Message.(error)
 				}
@@ -186,7 +158,8 @@ func NewListener(c <-chan InterServiceMessage) Listener {
 }
 
 func (l DefaultListener) AcceptMessage() InterServiceMessage {
-	return <-l
+	msg := <-l
+	return msg
 }
 
 func (s *ServiceInitializationInformation) SendISMessage(forService uuid.UUID, messageType MessageCode, message any) uuid.UUID {
@@ -199,24 +172,55 @@ func (s *ServiceInitializationInformation) SendISMessage(forService uuid.UUID, m
 		SentAt:       time.Now(),
 		Message:      message,
 	}
+	s.internal.mutex.Lock()
+	s.internal.waitingList[id] = struct{}{}
+	s.internal.mutex.Unlock()
 	s.Outbox <- msg
 	return id
 }
 
-func (s *ServiceInitializationInformation) SendAndAwaitISMessage(forService uuid.UUID, messageType MessageCode, message any, timeout time.Duration) (InterServiceMessage, error) {
-	id := s.SendISMessage(forService, messageType, message)
-	return AwaitISMessage(id, timeout)
+func (s *InterServiceMessage) Respond(messageType MessageCode, message any, information *ServiceInitializationInformation) {
+	n := *s
+	n.ServiceID, n.ForServiceID = n.ForServiceID, n.ServiceID
+	n.MessageType = messageType
+	n.Message = message
+	n.SentAt = time.Now()
+	information.Outbox <- n
 }
 
+func (s *ServiceInitializationInformation) SendAndAwaitISMessage(forService uuid.UUID, messageType MessageCode, message any, timeout time.Duration) (InterServiceMessage, error) {
+	id := s.SendISMessage(forService, messageType, message)
+	return s.AwaitISMessage(id, timeout)
+}
+
+var databaseService = uuid.MustParse("00000000-0000-0000-0000-000000000001")
+
 func (s *ServiceInitializationInformation) GetDatabase() (Database, error) {
-	if !ispStarted {
+	if !s.internal.ispStarted {
 		go s.StartISProcessor()
 	}
 
-	response, err := s.SendAndAwaitISMessage(uuid.Nil, 0, nil, 5*time.Second)
+	response, err := s.SendAndAwaitISMessage(databaseService, 0, nil, 5*time.Second)
 	if err != nil {
-		return nil, err
+		return Database{}, err
 	}
 
 	return response.Message.(Database), nil
 }
+
+func (s *ServiceInitializationInformation) AcceptMessage() InterServiceMessage {
+	for {
+		<-s.internal.arrived
+		s.internal.mutex.Lock()
+		for id, msg := range s.internal.buffer {
+			_, ok := s.internal.waitingList[id]
+
+			if !ok {
+				delete(s.internal.buffer, id)
+				s.internal.mutex.Unlock()
+				return msg
+			}
+		}
+		s.internal.mutex.Unlock()
+	}
+}