From: Christian Heller <c.heller@plomlompom.de>
Date: Wed, 27 Mar 2024 02:29:03 +0000 (+0100)
Subject: Add PostvarsParser to isolate postvars parsing/checking.
X-Git-Url: https://plomlompom.com/repos/%7B%7Bprefix%7D%7D/static/%7B%7Byoutube_prefix%7D%7D%7B%7Bvideo_id%7D%7D?a=commitdiff_plain;h=8aa3103f8e131b8925ac9daafadf2db77886c910;p=plomtask

Add PostvarsParser to isolate postvars parsing/checking.
---

diff --git a/plomtask/http.py b/plomtask/http.py
index 3396125..933662f 100644
--- a/plomtask/http.py
+++ b/plomtask/http.py
@@ -24,6 +24,28 @@ class TaskServer(HTTPServer):
         self.jinja = JinjaEnv(loader=JinjaFSLoader(TEMPLATES_DIR))
 
 
+class PostvarsParser:
+    """Postvars wrapper for validating and retrieving posted form data."""
+
+    def __init__(self, postvars: dict[str, list[str]]) -> None:
+        self.postvars = postvars
+
+    def get_str(self, key: str) -> str:
+        """Retrieve string value of key from self.postvars."""
+        if key not in self.postvars:
+            raise BadFormatException(f'missing value for form field: {key}')
+        return self.postvars[key][0]
+
+    def get_float(self, key: str) -> float:
+        """Retrieve float value of key from self.postvars."""
+        val = self.get_str(key)
+        try:
+            return float(val)
+        except ValueError as e:
+            msg = f'cannot float form field value: {val}'
+            raise BadFormatException(msg) from e
+
+
 class TaskHandler(BaseHTTPRequestHandler):
     """Handles single HTTP request."""
     server: TaskServer
@@ -87,48 +109,37 @@ class TaskHandler(BaseHTTPRequestHandler):
             length = int(self.headers['content-length'])
             postvars = parse_qs(self.rfile.read(length).decode(),
                                 keep_blank_values=True)
+            form_data = PostvarsParser(postvars)
             if 'day' == site:
                 date = params.get('date', [''])[0]
-                self.do_POST_day(conn, date, postvars)
+                self.do_POST_day(conn, date, form_data)
             elif 'process' == site:
                 id_ = params.get('id', [''])[0]
                 try:
                     id__ = int(id_) if id_ else None
                 except ValueError as e:
                     raise BadFormatException(f'Bad ?id= value: {id_}') from e
-                self.do_POST_process(conn, id__, postvars)
+                self.do_POST_process(conn, id__, form_data)
             conn.commit()
             conn.close()
             self._redirect('/')
         except HandledException as error:
             self._send_msg(error, code=error.http_code)
 
-    def do_POST_day(self, conn: DatabaseConnection,
-                    date: str, postvars: dict[str, list[str]]) -> None:
+    def do_POST_day(self, conn: DatabaseConnection, date: str,
+                    form_data: PostvarsParser) -> None:
         """Update or insert Day of date and fields defined in postvars."""
         day = Day.by_date(conn, date, create=True)
-        if 'comment' not in postvars.keys():
-            raise BadFormatException('missing Day.comment value')
-        day.comment = postvars['comment'][0]
+        day.comment = form_data.get_str('comment')
         day.save(conn)
 
     def do_POST_process(self, conn: DatabaseConnection, id_: int | None,
-                        postvars: dict[str, list[str]]) -> None:
+                        form_data: PostvarsParser) -> None:
         """Update or insert Process of id_ and fields defined in postvars."""
         process = Process.by_id(conn, id_, create=True)
-        if 'title' not in postvars.keys():
-            raise BadFormatException('missing Process.title value')
-        if 'description' not in postvars.keys():
-            raise BadFormatException('missing Process.description value')
-        if 'effort' not in postvars.keys():
-            raise BadFormatException('missing Process.effort value')
-        process.title.set(postvars['title'][0])
-        process.description.set(postvars['description'][0])
-        effort = postvars['effort'][0]
-        try:
-            process.effort.set(float(effort))
-        except ValueError as e:
-            raise BadFormatException(f'Bad effort value: {effort}') from e
+        process.title.set(form_data.get_str('title'))
+        process.description.set(form_data.get_str('description'))
+        process.effort.set(form_data.get_float('effort'))
         process.save(conn)
 
     def _init_handling(self) -> \