Fix lint

backend/grading/runner.go

@@ -161,8 +161,11 @@ func Grade(id string, job Job, results chan<- Result) {
 	defer os.RemoveAll(dir)
 	studentWorkFilePath := path.Join(dir, "work.tar.gz")
 	tmpFile, _ := os.Create(studentWorkFilePath)
-	io.Copy(tmpFile, job.File)
 	defer tmpFile.Close()
+	if _, err := io.Copy(tmpFile, job.File); err != nil {
+		fmt.Println(err)
+		return
+	}
 
 	// Execute grading script driver.
 	cmd := exec.Command(job.Script, studentWorkFilePath)

backend/handler/assignment.go

@@ -128,7 +128,9 @@ func GetAssignment(cc echo.Context) error {
 	}
 	for ok := rows.Next(); ok; ok = rows.Next() {
 		id, owner, date, points := "", "", time.Time{}, float64(0)
-		rows.Scan(&id, &owner, &date, &points)
+		if err := rows.Scan(&id, &owner, &date, &points); err != nil {
+			c.Logger().Error(err)
+		}
 		submissions = append(submissions, struct {
 			ID            string    "json:\"id\""
 			OwnerUsername string    "json:\"owner\""

backend/handler/class.go

@@ -47,7 +47,9 @@ func GetClass(cc echo.Context) error {
 	}
 	for ok := rows.Next(); ok; ok = rows.Next() {
 		id, name, dueDate, points := 0, "", time.Time{}, float64(0)
-		rows.Scan(&id, &name, &dueDate, &points)
+		if err := rows.Scan(&id, &name, &dueDate, &points); err != nil {
+			c.Logger().Error(err)
+		}
 		assignments = append(assignments, struct {
 			ID      int       "json:\"id\""
 			Name    string    "json:\"name\""

backend/handler/user.go

@@ -161,7 +161,9 @@ func GetUser(cc echo.Context) error {
 	for ok := rows.Next(); ok; ok = rows.Next() {
 		id := 0
 		name := ""
-		rows.Scan(&id, &name)
+		if err := rows.Scan(&id, &name); err != nil {
+			c.Logger().Error(err)
+		}
 		response.Classes = append(response.Classes, struct {
 			ID   int    "json:\"id\""
 			Name string "json:\"name\""
@@ -182,7 +184,9 @@ func GetUser(cc echo.Context) error {
 	}
 	for ok := rows.Next(); ok; ok = rows.Next() {
 		id, class, name, dueDate, points := 0, 0, "", time.Time{}, float64(0)
-		rows.Scan(&id, &class, &name, &dueDate, &points)
+		if err := rows.Scan(&id, &class, &name, &dueDate, &points); err != nil {
+			c.Logger().Error(err)
+		}
 		response.Assignments = append(response.Assignments, struct {
 			ID             int       "json:\"id\""
 			Class          int       "json:\"class\""