Initial commit

Proof-of-concept implementation. Bugs will occur.

internal/application/application.go

@@ -0,0 +1,118 @@
+package application
+
+import (
+	"context"
+	"fmt"
+	"runtime"
+	"sync"
+
+	"github.com/sirupsen/logrus"
+	"source.hodakov.me/hdkv/faketunes/internal/configuration"
+	"source.hodakov.me/hdkv/faketunes/internal/domains"
+)
+
+type App struct {
+	ctx    context.Context
+	logger *logrus.Entry
+	config *configuration.Config
+
+	domains      map[string]domains.Domain
+	domainsMutex sync.RWMutex
+}
+
+func (a *App) Config() *configuration.Config {
+	return a.config
+}
+
+func (a *App) Context() context.Context {
+	return a.ctx
+}
+
+func (a *App) Logger() *logrus.Entry {
+	return a.logger
+}
+
+func New(ctx context.Context) *App {
+	var m runtime.MemStats
+	runtime.ReadMemStats(&m)
+
+	app := new(App)
+
+	// Initialize standard logger with memory stats and context attached permanently.
+	logger := logrus.StandardLogger()
+
+	logger.SetFormatter(&logrus.TextFormatter{
+		FullTimestamp: true,
+	})
+
+	app.logger = logger.WithContext(ctx).WithFields(logrus.Fields{
+		"memalloc": fmt.Sprintf("%dMB", m.Alloc/1024/1024),
+		"memsys":   fmt.Sprintf("%dMB", m.Sys/1024/1024),
+		"numgc":    fmt.Sprintf("%d", m.NumGC),
+	})
+
+	app.ctx = ctx
+
+	app.domains = make(map[string]domains.Domain)
+
+	return app
+}
+
+func (a *App) InitConfig() error {
+	config, err := configuration.New()
+	if err != nil {
+		return fmt.Errorf("%w: %w (%w)", ErrApplication, ErrConfigInitializationError, err)
+	}
+
+	a.config = config
+
+	return nil
+}
+
+func (a *App) InitLogger() {
+	a.logger.Logger.SetLevel(a.config.FakeTunes.LogLevel)
+
+	a.logger.WithField("log level", a.config.FakeTunes.LogLevel).Debug("Set log level")
+}
+
+func (a *App) RegisterDomain(name string, implementation domains.Domain) {
+	a.domainsMutex.Lock()
+	defer a.domainsMutex.Unlock()
+
+	a.domains[name] = implementation
+}
+
+func (a *App) RetrieveDomain(name string) any {
+	a.domainsMutex.RLock()
+	defer a.domainsMutex.RUnlock()
+
+	return a.domains[name]
+}
+
+func (a *App) ConnectDependencies() error {
+	a.domainsMutex.RLock()
+	defer a.domainsMutex.RUnlock()
+
+	for _, domain := range a.domains {
+		err := domain.ConnectDependencies()
+		if err != nil {
+			return fmt.Errorf("%w: %w (%w)", ErrApplication, ErrConnectDependencies, err)
+		}
+	}
+
+	return nil
+}
+
+func (a *App) StartDomains() error {
+	a.domainsMutex.RLock()
+	defer a.domainsMutex.RUnlock()
+
+	for _, domain := range a.domains {
+		err := domain.Start()
+		if err != nil {
+			return fmt.Errorf("%w: %w (%w)", ErrApplication, ErrDomainInit, err)
+		}
+	}
+
+	return nil
+}