Implement login endpoint

validator/login.go

@@ -0,0 +1,62 @@
+package main
+
+import (
+	"encoding/json"
+	"log"
+	"net/http"
+)
+
+type loginChecker struct{
+	students []Student
+}
+
+type loginUpload struct {
+	Username string
+	Password string
+}
+
+func (l loginChecker) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	if addr := r.Header.Get("X-Forwarded-For"); addr != "" {
+		r.RemoteAddr = addr
+	}
+	log.Printf("%s \"%s %s\" [%s]\n", r.RemoteAddr, r.Method, r.URL.Path, r.UserAgent())
+
+	w.Header().Set("Content-Type", "text/plain")
+
+	// Check request type and size
+	if r.Method != "POST" {
+		http.Error(w,
+			"Invalid request",
+			http.StatusBadRequest)
+		return
+	} else if r.ContentLength < 0 || r.ContentLength > 1023 {
+		http.Error(w,
+			"Request entity too large",
+			http.StatusRequestEntityTooLarge)
+		return
+	}
+
+	dec := json.NewDecoder(r.Body)
+	var lu loginUpload
+	if err := dec.Decode(&lu); err != nil {
+		http.Error(w,
+			err.Error(),
+			http.StatusBadRequest)
+		return
+	}
+
+	// Perform login check
+	canContinue := false
+	for _, std := range l.students {
+		if std.Login == lu.Username {
+			canContinue = true
+		}
+	}
+
+	if !canContinue {
+		http.Error(w, "Login not found in whitelist.", http.StatusUnauthorized)
+		return
+	}
+
+	http.Error(w, "Success", http.StatusOK)
+}