add a new example

_examples/configuration/multi-environments/api/configuration.go

@@ -0,0 +1,27 @@
+package api
+
+import (
+	"os"
+
+	"github.com/kataras/iris/v12"
+	"gopkg.in/yaml.v3"
+)
+
+type Configuration struct {
+	Host              string `yaml:"Host"`
+	Port              int    `yaml:"Port"`
+	EnableCompression bool   `yaml:"EnableCompression"`
+	AllowOrigin       string `yaml:"AllowOrigin"`
+	// Iris specific configuration.
+	Iris iris.Configuration `yaml:"Iris"`
+}
+
+// BindFile binds the yaml file's contents to this Configuration.
+func (c *Configuration) BindFile(filename string) error {
+	contents, err := os.ReadFile(filename)
+	if err != nil {
+		return err
+	}
+
+	return yaml.Unmarshal(contents, c)
+}

_examples/configuration/multi-environments/api/server.go

@@ -0,0 +1,120 @@
+package api
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/kataras/iris/v12"
+	"github.com/kataras/iris/v12/middleware/cors"
+	"github.com/kataras/iris/v12/x/errors"
+)
+
+type Server struct {
+	*iris.Application
+
+	config  Configuration
+	closers []func() // See "AddCloser" method.
+}
+
+// NewServer returns a new server instance.
+// See its "Start" method.
+func NewServer(congig Configuration) *Server {
+	app := iris.New()
+	app.Configure(iris.WithConfiguration(congig.Iris))
+
+	s := &Server{
+		config:      congig,
+		Application: app,
+	}
+
+	return s
+}
+
+func (s *Server) Build() error {
+	if err := s.Application.Build(); err != nil {
+		return err
+	}
+
+	// Register your 3rd-party drivers.
+	// if err := s.registerDatabase(); err != nil {
+	// 	return err
+	// }s
+
+	return s.configureRouter()
+}
+
+func (s *Server) configureRouter() error {
+	s.SetContextErrorHandler(errors.DefaultContextErrorHandler)
+	s.Macros().SetErrorHandler(errors.DefaultPathParameterTypeErrorHandler)
+
+	s.registerMiddlewares()
+	s.registerRoutes()
+
+	return nil
+}
+
+func (s *Server) registerMiddlewares() {
+	s.UseRouter(cors.New().AllowOrigin(s.config.AllowOrigin).Handler())
+
+	s.UseRouter(func(ctx iris.Context) {
+		ctx.Header("Server", "Iris")
+		ctx.Header("X-Developer", "kataras")
+		ctx.Next()
+	})
+
+	if s.config.EnableCompression {
+		s.Use(iris.Compression) // .Use instead of .UseRouter to let it run only on registered routes and not on 404 errors and e.t.c.
+	}
+}
+
+func (s *Server) registerRoutes() {
+	// register your routes...
+
+	s.Get("/health", func(ctx iris.Context) {
+		ctx.WriteString("OK")
+	})
+
+}
+
+// AddCloser adds one or more function that should be called on
+// manual server shutdown or OS interrupt signals.
+func (s *Server) AddCloser(closers ...func()) {
+	for _, closer := range closers {
+		if closer == nil {
+			continue
+		}
+
+		// Terminate any opened connections on OS interrupt signals.
+		iris.RegisterOnInterrupt(closer)
+	}
+
+	s.closers = append(s.closers, closers...)
+}
+
+// Shutdown gracefully terminates the HTTP server and calls the closers afterwards.
+func (s *Server) Shutdown() error {
+	ctx, cancelCtx := context.WithTimeout(context.Background(), 5*time.Second)
+	err := s.Application.Shutdown(ctx)
+	cancelCtx()
+
+	for _, closer := range s.closers {
+		if closer == nil {
+			continue
+		}
+
+		closer()
+	}
+
+	return err
+}
+
+// Start starts the http server based on the config's host and port.
+func (s *Server) Listen() error {
+	if err := s.Build(); err != nil {
+		return err
+	}
+
+	addr := fmt.Sprintf("%s:%d", s.config.Host, s.config.Port)
+	return s.Application.Listen(addr)
+}