package rushlink import ( "fmt" "log" "net/http" "net/url" "runtime/debug" "strconv" "time" "gitea.hashru.nl/dsprenkels/rushlink/internal/db" "github.com/gorilla/mux" "github.com/pkg/errors" ) const staticFilenameExpr = "[A-Za-z0-9-_.]+" const urlKeyExpr = "{key:[A-Za-z0-9-_]{4,}}" const urlKeyWithExtExpr = urlKeyExpr + "{ext:\\.[A-Za-z0-9-_]+}" type rushlink struct { db *db.Database fs *db.FileStore rootURL *url.URL } func (rl *rushlink) RootURL() *url.URL { return rl.rootURL } func (rl *rushlink) recoveryMiddleware(next http.Handler) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { logRequestInfo := func() { log.Printf("in request: %v - %v %q %v", r.RemoteAddr, r.Method, r.RequestURI, r.Proto) } defer func() { defer func() { if err := recover(); err != nil { w.WriteHeader(500) log.Printf("error: panic while recovering from another panic: %v\n", err) logRequestInfo() debug.PrintStack() fmt.Fprintf(w, "internal server error: %v\n", err) } }() if err := recover(); err != nil { w.WriteHeader(500) log.Printf("error: %v\n", err) logRequestInfo() debug.PrintStack() rl.renderInternalServerError(w, r, err) } }() next.ServeHTTP(w, r) }) } func (rl *rushlink) metricsMiddleware(next http.Handler) http.Handler { return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { srw := statusResponseWriter{Inner: w} next.ServeHTTP(&srw, r) status := strconv.Itoa(srw.StatusCode) labels := map[string]string{"code": status, "method": r.Method} // Update requests counter metric metricRequestsTotalCounter.With(labels).Inc() }) } type statusResponseWriter struct { Inner http.ResponseWriter StatusCode int } func (w *statusResponseWriter) Header() http.Header { return w.Inner.Header() } func (w *statusResponseWriter) Write(buf []byte) (int, error) { if w.StatusCode == 0 { w.WriteHeader(http.StatusOK) } return w.Inner.Write(buf) } func (w *statusResponseWriter) WriteHeader(statusCode int) { w.StatusCode = statusCode w.Inner.WriteHeader(statusCode) } // InitMainRouter creates the main Gorilla router for the application. // // This function will not populate the router with an error-recovery and // metrics-reporting middleware. If these middleware are required, then the // caller should encapsulate this router inside of another router and register // the middlewares on the encapsulating router. func InitMainRouter(r *mux.Router, rl *rushlink) { r.HandleFunc("/{path:img/"+staticFilenameExpr+"}", rl.staticGetHandler).Methods("GET", "HEAD") r.HandleFunc("/{path:css/"+staticFilenameExpr+"}", rl.staticGetHandler).Methods("GET", "HEAD") r.HandleFunc("/{path:js/"+staticFilenameExpr+"}", rl.staticGetHandler).Methods("GET", "HEAD") r.HandleFunc("/", rl.indexGetHandler).Methods("GET", "HEAD") r.HandleFunc("/", rl.newPasteHandler).Methods("POST") r.HandleFunc("/"+urlKeyExpr, rl.viewPasteHandler).Methods("GET", "HEAD") r.HandleFunc("/"+urlKeyWithExtExpr, rl.viewPasteHandler).Methods("GET", "HEAD") r.HandleFunc("/"+urlKeyExpr+"/nr", rl.viewPasteHandlerNoRedirect).Methods("GET", "HEAD") r.HandleFunc("/"+urlKeyWithExtExpr+"/nr", rl.viewPasteHandlerNoRedirect).Methods("GET", "HEAD") r.HandleFunc("/"+urlKeyExpr+"/meta", rl.viewPasteHandlerMeta).Methods("GET", "HEAD") r.HandleFunc("/"+urlKeyWithExtExpr+"/meta", rl.viewPasteHandlerMeta).Methods("GET", "HEAD") r.HandleFunc("/"+urlKeyExpr, rl.deletePasteHandler).Methods("DELETE") r.HandleFunc("/"+urlKeyWithExtExpr, rl.deletePasteHandler).Methods("DELETE") r.HandleFunc("/"+urlKeyExpr+"/delete", rl.deletePasteHandler).Methods("POST") r.HandleFunc("/"+urlKeyWithExtExpr+"/delete", rl.deletePasteHandler).Methods("POST") } // StartMainServer starts the main http server listening on addr. func StartMainServer(addr string, db *db.Database, fs *db.FileStore, rawRootURL string) { var rootURL *url.URL if rawRootURL != "" { var err error rootURL, err = url.Parse(rawRootURL) if err != nil { log.Fatalln(errors.Wrap(err, "could not parse rootURL flag")) } } rl := rushlink{ db: db, fs: fs, rootURL: rootURL, } router := mux.NewRouter() router.Use(rl.metricsMiddleware) router.Use(rl.recoveryMiddleware) InitMainRouter(router, &rl) srv := &http.Server{ Handler: router, Addr: addr, WriteTimeout: 15 * time.Second, ReadTimeout: 15 * time.Second, } log.Fatal(srv.ListenAndServe()) }