Initial commit

main.go

@@ -0,0 +1,112 @@
+package main
+
+import (
+	"context"
+	"flag"
+	"fmt"
+	"log"
+	"net/http"
+	"net/url"
+	"os"
+	"os/signal"
+	"path"
+	"strings"
+	"syscall"
+)
+
+var baseURL string = "/"
+
+type ResponseWriterPrefix struct {
+	real   http.ResponseWriter
+	prefix string
+}
+
+func (r ResponseWriterPrefix) Header() http.Header {
+	return r.real.Header()
+}
+
+func (r ResponseWriterPrefix) WriteHeader(s int) {
+	if v, exists := r.real.Header()["Location"]; exists && len(v) > 0 && !strings.HasPrefix(v[0], "https://") && !strings.HasPrefix(v[0], "http://") {
+		r.real.Header().Set("Location", r.prefix+v[0])
+	}
+	r.real.WriteHeader(s)
+}
+
+func (r ResponseWriterPrefix) Write(z []byte) (int, error) {
+	return r.real.Write(z)
+}
+
+func StripPrefix(prefix string, h http.Handler) http.Handler {
+	if prefix == "" {
+		return h
+	}
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if prefix != "/" && r.URL.Path == "/" {
+			http.Redirect(w, r, prefix+"/", http.StatusFound)
+		} else if p := strings.TrimPrefix(r.URL.Path, prefix); len(p) < len(r.URL.Path) {
+			r2 := new(http.Request)
+			*r2 = *r
+			r2.URL = new(url.URL)
+			*r2.URL = *r.URL
+			r2.URL.Path = p
+			h.ServeHTTP(ResponseWriterPrefix{w, prefix}, r2)
+		} else {
+			h.ServeHTTP(w, r)
+		}
+	})
+}
+
+func main() {
+	var bind = flag.String("bind", ":8081", "Bind port/socket")
+	var dsn = flag.String("dsn", DSNGenerator(), "DSN to connect to the MySQL server")
+	flag.StringVar(&baseURL, "baseurl", baseURL, "URL prepended to each URL")
+	flag.Parse()
+
+	// Sanitize options
+	var err error
+	log.Println("Checking paths...")
+	if err = sanitizeStaticOptions(); err != nil {
+		log.Fatal(err)
+	}
+	if baseURL != "/" {
+		baseURL = path.Clean(baseURL)
+	} else {
+		baseURL = ""
+	}
+
+	initializeOIDC()
+
+	// Initialize contents
+	log.Println("Opening database...")
+	if err := DBInit(*dsn); err != nil {
+		log.Fatal("Cannot open the database: ", err)
+	}
+	defer DBClose()
+
+	log.Println("Creating database...")
+	if err := DBCreate(); err != nil {
+		log.Fatal("Cannot create database: ", err)
+	}
+
+	// Prepare graceful shutdown
+	interrupt := make(chan os.Signal, 1)
+	signal.Notify(interrupt, os.Interrupt, syscall.SIGTERM)
+
+	srv := &http.Server{
+		Addr:    *bind,
+		Handler: StripPrefix(baseURL, Router()),
+	}
+
+	// Serve content
+	go func() {
+		log.Fatal(srv.ListenAndServe())
+	}()
+	log.Println(fmt.Sprintf("Ready, listening on %s", *bind))
+
+	// Wait shutdown signal
+	<-interrupt
+
+	log.Print("The service is shutting down...")
+	srv.Shutdown(context.Background())
+	log.Println("done")
+}