package httpserver import ( "context" "log" "net" "net/http" "strings" "time" "go.dev.pztrn.name/metricator/internal/common" "go.dev.pztrn.name/metricator/internal/configuration" ) // HTTPServer is a controlling structure for HTTP server. type HTTPServer struct { config *configuration.Config ctx context.Context doneChan chan struct{} handler *handler server *http.Server } func NewHTTPServer(ctx context.Context, cfg *configuration.Config) (*HTTPServer, chan struct{}) { h := &HTTPServer{ config: cfg, ctx: ctx, doneChan: make(chan struct{}), } h.initialize() return h, h.doneChan } // Returns request's context based on main context of application. // Basically it returns main context and does nothing more. func (h *HTTPServer) getRequestContext(_ net.Listener) context.Context { return h.ctx } // Initializes handler and HTTP server structure. func (h *HTTPServer) initialize() { h.handler = &handler{ handlers: make(map[string]common.HTTPHandlerFunc), } // We do not need to specify all possible parameters for HTTP server, so: // nolint:exhaustivestruct h.server = &http.Server{ // ToDo: make it all configurable. Addr: ":34421", BaseContext: h.getRequestContext, Handler: h.handler, ReadTimeout: time.Second * 10, WriteTimeout: time.Second * 10, MaxHeaderBytes: 1 << 20, } } // RegisterHandlerForApplication registers HTTP handler for application. func (h *HTTPServer) RegisterHandlerForApplication(name string, handler common.HTTPHandlerFunc) { h.handler.register(name, handler) } // Start starts HTTP server in another goroutine and one more goroutine which // is listening to main context's Cancel() call to stop HTTP server. func (h *HTTPServer) Start() { go func() { err := h.server.ListenAndServe() if err != nil { if !strings.Contains(err.Error(), "Server closed") { log.Println("HTTP server failed to listen:", err.Error()) } } }() go func() { <-h.ctx.Done() log.Println("Shutting down HTTP server") err := h.server.Shutdown(h.ctx) if err != nil && !strings.Contains(err.Error(), "context canceled") { log.Println("Failed to stop HTTP server:", err.Error()) } log.Println("HTTP server stopped") h.doneChan <- struct{}{} }() }