feat(api): Migrate from gorilla/mux to fiber

Fixes #468

api/api.go

@@ -0,0 +1,106 @@
+package api
+
+import (
+	"io/fs"
+	"log"
+	"net/http"
+	"os"
+
+	"github.com/TwiN/gatus/v5/config"
+	static "github.com/TwiN/gatus/v5/web"
+	"github.com/TwiN/health"
+	fiber "github.com/gofiber/fiber/v2"
+	"github.com/gofiber/fiber/v2/middleware/adaptor"
+	"github.com/gofiber/fiber/v2/middleware/compress"
+	"github.com/gofiber/fiber/v2/middleware/cors"
+	fiberfs "github.com/gofiber/fiber/v2/middleware/filesystem"
+	"github.com/gofiber/fiber/v2/middleware/recover"
+	"github.com/gofiber/fiber/v2/middleware/redirect"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
+)
+
+type API struct {
+	router *fiber.App
+}
+
+func New(cfg *config.Config) *API {
+	api := &API{}
+	api.router = api.createRouter(cfg)
+	return api
+}
+
+func (a *API) Router() *fiber.App {
+	return a.router
+}
+
+func (a *API) createRouter(cfg *config.Config) *fiber.App {
+	app := fiber.New(fiber.Config{
+		ErrorHandler: func(c *fiber.Ctx, err error) error {
+			log.Printf("[api.ErrorHandler] %s", err.Error())
+			return fiber.DefaultErrorHandler(c, err)
+		},
+	})
+	if os.Getenv("ENVIRONMENT") == "dev" {
+		app.Use(cors.New(cors.Config{
+			AllowOrigins:     "http://localhost:8081",
+			AllowCredentials: true,
+		}))
+	}
+	apiRouter := app.Group("/api")
+	protectedAPIRouter := apiRouter.Group("/")
+	unprotectedAPIRouter := apiRouter.Group("/")
+	if cfg.Metrics {
+		metricsHandler := promhttp.InstrumentMetricHandler(prometheus.DefaultRegisterer, promhttp.HandlerFor(prometheus.DefaultGatherer, promhttp.HandlerOpts{
+			DisableCompression: true,
+		}))
+		app.Get("/metrics", adaptor.HTTPHandler(metricsHandler))
+	}
+	// Security (ORDER IS IMPORTANT: middlewares must be applied before the routes are registered)
+	if cfg.Security != nil {
+		if err := cfg.Security.RegisterHandlers(app); err != nil {
+			panic(err)
+		}
+		if err := cfg.Security.ApplySecurityMiddleware(protectedAPIRouter); err != nil {
+			panic(err)
+		}
+	}
+	// Middlewares
+	app.Use(recover.New())
+	app.Use(compress.New())
+	// Routes
+	handler := ConfigHandler{securityConfig: cfg.Security}
+	unprotectedAPIRouter.Get("/v1/config", handler.GetConfig)
+	protectedAPIRouter.Get("/v1/endpoints/statuses", EndpointStatuses(cfg))
+	protectedAPIRouter.Get("/v1/endpoints/:key/statuses", EndpointStatus)
+	unprotectedAPIRouter.Get("/v1/endpoints/:key/health/badge.svg", HealthBadge)
+	unprotectedAPIRouter.Get("/v1/endpoints/:key/uptimes/:duration/badge.svg", UptimeBadge)
+	unprotectedAPIRouter.Get("/v1/endpoints/:key/response-times/:duration/badge.svg", ResponseTimeBadge(cfg))
+	unprotectedAPIRouter.Get("/v1/endpoints/:key/response-times/:duration/chart.svg", ResponseTimeChart)
+	// SPA
+	app.Get("/", SinglePageApplication(cfg.UI))
+	app.Get("/endpoints/:name", SinglePageApplication(cfg.UI))
+	// Health endpoint
+	healthHandler := health.Handler().WithJSON(true)
+	app.Get("/health", func(c *fiber.Ctx) error {
+		statusCode, body := healthHandler.GetResponseStatusCodeAndBody()
+		return c.Status(statusCode).Send(body)
+	})
+	// Everything else falls back on static content
+	app.Use(redirect.New(redirect.Config{
+		Rules: map[string]string{
+			"/index.html": "/",
+		},
+		StatusCode: 301,
+	}))
+	staticFileSystem, err := fs.Sub(static.FileSystem, static.RootPath)
+	if err != nil {
+		panic(err)
+	}
+	app.Use("/", fiberfs.New(fiberfs.Config{
+		Root:   http.FS(staticFileSystem),
+		Index:  "index.html",
+		Browse: true,
+	}))
+	return app
+}