Be sure db file exist

src/handlers/main.lisp

@@ -1,9 +1,7 @@
 (in-package :ml-survey/handlers)
 
 (defvar *survey-data-dir*
-  (ensure-directories-exist (format nil
-                                    "~adata/survey/"
-                                    (uiop:getcwd))))
+  (ensure-directories-exist (uiop:merge-pathnames* "data/survey")))
 
 (defun split-uri (uri)
   (check-type uri string)
@@ -22,11 +20,23 @@
                                 (local-time:now)
                                 :format '((:hour 2) ":" (:min 2) ":" (:sec 2))))
 
-(defun make-db-path (date-str file-str)
-  (pathname (concatenate 'string date-str file-str)))
+(defun ensure-file-exists (pathname)
+  "Ensure that a file specified by PATHNAME exists, create it if it doesn't."
+  (unless (uiop:file-exists-p pathname)
+    (with-open-file (stream pathname
+                            :direction :output
+                            :if-exists :overwrite
+                            :if-does-not-exist :create)
+      (format stream "")))
+  pathname)
 
-(defun make-surveys-db-path ()
-  (make-db-path (today) "-surveys-db.lisp"))
+(defun make-db-file (file-str)
+  "Prepare and ensure a database file at FILE-STR path."
+  (let ((path (uiop:merge-pathnames* file-str)))
+    (ensure-file-exits (truename path))))
+
+(defun make-surveys-db-file ()
+  (make-db-file "surveys-db.lisp"))
 
 (defun load-response (db)
   (check-type db (or string pathname))