frontend: refactor submission handlers

frontend/submissions.go

@@ -0,0 +1,67 @@
+package main
+
+import (
+	"log"
+	"net/http"
+	"os"
+	"path"
+	"strings"
+)
+
+type submissionHandler func(w http.ResponseWriter, r *http.Request, sURL []string)
+
+type submissionChecker struct{
+	kind     string
+	next     submissionHandler
+}
+
+type submissionTeamHandler func(w http.ResponseWriter, r *http.Request, team string, sURL []string)
+
+type submissionTeamChecker struct{
+	kind     string
+	next     submissionTeamHandler
+	teamsDir string
+}
+
+func (c submissionChecker) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	log.Printf("Handling %s %s request from %s: %s [%s]\n", r.Method, c.kind, r.RemoteAddr, r.URL.Path, r.UserAgent())
+
+	w.Header().Set("Content-Type", "application/json")
+
+	// Check request type and size
+	if r.Method != "POST" {
+		http.Error(w, "{\"errmsg\":\"Requête invalide.\"}", http.StatusBadRequest)
+		return
+	} else if r.ContentLength < 0 || r.ContentLength > 1023 {
+		http.Error(w, "{\"errmsg\":\"Requête trop longue ou de taille inconnue\"}", http.StatusRequestEntityTooLarge)
+		return
+	}
+
+	// Extract URL arguments
+	var sURL = strings.Split(r.URL.Path, "/")
+
+	c.next(w, r, sURL)
+}
+
+func (c submissionTeamChecker) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	submissionChecker{c.kind, func(w http.ResponseWriter, r *http.Request, sURL []string){
+		if len(sURL) < 1 {
+			http.Error(w, "{\"errmsg\":\"Arguments manquants.\"}", http.StatusBadRequest)
+			return
+		}
+		team := sURL[0]
+
+		// Check team validity and existance
+		if len(team) < 1 || team[0] == '_' {
+			log.Println("INVALID TEAM:", team)
+			http.Error(w, "{\"errmsg\":\"Équipe inexistante.\"}", http.StatusBadRequest)
+			return
+		} else if _, err := os.Stat(path.Join(c.teamsDir, team)); os.IsNotExist(err) {
+			log.Println("UNKNOWN TEAM:", team)
+			http.Error(w, "{\"errmsg\":\"Équipe inexistante.\"}", http.StatusBadRequest)
+			return
+		}
+
+		c.next(w, r, team, sURL[1:])
+	}}.ServeHTTP(w, r)
+}