X-Git-Url: https://plomlompom.com/repos/berlin_corona.txt?a=blobdiff_plain;f=plomtask%2Fhttp.py;h=f5160f64d2504a3cf40733668623e1475eaa0cd8;hb=HEAD;hp=d602f07b9baf3c18df19fa88435928d2a33845d6;hpb=db62e6559fdd577dae38d4b6f5cbd5ef6a14cc57;p=plomtask

diff --git a/plomtask/http.py b/plomtask/http.py
index d602f07..b7040f7 100644
--- a/plomtask/http.py
+++ b/plomtask/http.py
@@ -3,6 +3,7 @@ from __future__ import annotations
 from dataclasses import dataclass
 from typing import Any, Callable
 from base64 import b64encode, b64decode
+from binascii import Error as binascii_Exception
 from http.server import BaseHTTPRequestHandler
 from http.server import HTTPServer
 from urllib.parse import urlparse, parse_qs
@@ -11,13 +12,12 @@ from os.path import split as path_split
 from jinja2 import Environment as JinjaEnv, FileSystemLoader as JinjaFSLoader
 from plomtask.dating import date_in_n_days
 from plomtask.days import Day
-from plomtask.exceptions import HandledException, BadFormatException, \
-        NotFoundException
+from plomtask.exceptions import (HandledException, BadFormatException,
+                                 NotFoundException)
 from plomtask.db import DatabaseConnection, DatabaseFile
 from plomtask.processes import Process, ProcessStep, ProcessStepsNode
 from plomtask.conditions import Condition
 from plomtask.todos import Todo
-from plomtask.db import BaseModel
 
 TEMPLATES_DIR = 'templates'
 
@@ -42,15 +42,25 @@ class TaskServer(HTTPServer):
     def ctx_to_json(ctx: dict[str, object]) -> str:
         """Render ctx into JSON string."""
         def walk_ctx(node: object) -> Any:
-            if isinstance(node, BaseModel):
+            if hasattr(node, 'as_dict_into_reference'):
+                if hasattr(node, 'id_') and node.id_ is not None:
+                    return node.as_dict_into_reference(library)
+            if hasattr(node, 'as_dict'):
                 return node.as_dict
             if isinstance(node, (list, tuple)):
                 return [walk_ctx(x) for x in node]
+            if isinstance(node, dict):
+                d = {}
+                for k, v in node.items():
+                    d[k] = walk_ctx(v)
+                return d
             if isinstance(node, HandledException):
                 return str(node)
             return node
+        library: dict[str, dict[str | int, object]] = {}
         for k, v in ctx.items():
             ctx[k] = walk_ctx(v)
+        ctx['_library'] = library
         return json_dumps(ctx)
 
     def render(self, ctx: dict[str, object], tmpl_name: str = '') -> str:
@@ -128,6 +138,20 @@ class InputsParser:
             msg = f'cannot int a form field value for key {key} in: {all_str}'
             raise BadFormatException(msg) from e
 
+    def get_all_floats_or_nones(self, key: str) -> list[float | None]:
+        """Retrieve list of float value at key, None if empty strings."""
+        ret: list[float | None] = []
+        for val in self.get_all_str(key):
+            if '' == val:
+                ret += [None]
+            else:
+                try:
+                    ret += [float(val)]
+                except ValueError as e:
+                    msg = f'cannot float form field value for key {key}: {val}'
+                    raise BadFormatException(msg) from e
+        return ret
+
 
 class TaskHandler(BaseHTTPRequestHandler):
     """Handles single HTTP request."""
@@ -143,7 +167,7 @@ class TaskHandler(BaseHTTPRequestHandler):
                    tmpl_name: str,
                    code: int = 200
                    ) -> None:
-        """Send HTML as proper HTTP response."""
+        """Send ctx as proper HTTP response."""
         body = self.server.render(ctx, tmpl_name)
         self.send_response(code)
         for header_tuple in self.server.headers:
@@ -154,6 +178,38 @@ class TaskHandler(BaseHTTPRequestHandler):
     @staticmethod
     def _request_wrapper(http_method: str, not_found_msg: str
                          ) -> Callable[..., Callable[[TaskHandler], None]]:
+        """Wrapper for do_GET… and do_POST… handlers, to init and clean up.
+
+        Among other things, conditionally cleans all caches, but only on POST
+        requests, as only those are expected to change the states of objects
+        that may be cached, and certainly only those are expected to write any
+        changes to the database. We want to call them as early though as
+        possible here, either exactly after the specific request handler
+        returns successfully, or right after any exception is triggered –
+        otherwise, race conditions become plausible.
+
+        Note that otherwise any POST attempt, even a failed one, may end in
+        problematic inconsistencies:
+
+        - if the POST handler experiences an Exception, changes to objects
+          won't get written to the DB, but the changed objects may remain in
+          the cache and affect other objects despite their possibly illegal
+          state
+
+        - even if an object was just saved to the DB, we cannot be sure its
+          current state is completely identical to what we'd get if loading it
+          fresh from the DB (e.g. currently Process.n_owners is only updated
+          when loaded anew via .from_table_row, nor is its state written to
+          the DB by .save; a questionable design choice, but proof that we
+          have no guarantee that objects' .save stores all their states we'd
+          prefer at their most up-to-date.
+        """
+
+        def clear_caches() -> None:
+            for cls in (Day, Todo, Condition, Process, ProcessStep):
+                assert hasattr(cls, 'empty_cache')
+                cls.empty_cache()
+
         def decorator(f: Callable[..., str | None]
                       ) -> Callable[[TaskHandler], None]:
             def wrapper(self: TaskHandler) -> None:
@@ -170,6 +226,8 @@ class TaskHandler(BaseHTTPRequestHandler):
                     if hasattr(self, handler_name):
                         handler = getattr(self, handler_name)
                         redir_target = f(self, handler)
+                        if 'POST' == http_method:
+                            clear_caches()
                         if redir_target:
                             self.send_response(302)
                             self.send_header('Location', redir_target)
@@ -178,9 +236,8 @@ class TaskHandler(BaseHTTPRequestHandler):
                         msg = f'{not_found_msg}: {self._site}'
                         raise NotFoundException(msg)
                 except HandledException as error:
-                    for cls in (Day, Todo, Condition, Process, ProcessStep):
-                        assert hasattr(cls, 'empty_cache')
-                        cls.empty_cache()
+                    if 'POST' == http_method:
+                        clear_caches()
                     ctx = {'msg': error}
                     self._send_page(ctx, 'msg', error.http_code)
                 finally:
@@ -212,6 +269,25 @@ class TaskHandler(BaseHTTPRequestHandler):
 
     # GET handlers
 
+    @staticmethod
+    def _get_item(target_class: Any
+                  ) -> Callable[..., Callable[[TaskHandler],
+                                              dict[str, object]]]:
+        def decorator(f: Callable[..., dict[str, object]]
+                      ) -> Callable[[TaskHandler], dict[str, object]]:
+            def wrapper(self: TaskHandler) -> dict[str, object]:
+                # pylint: disable=protected-access
+                # (because pylint here fails to detect the use of wrapper as a
+                # method to self with respective access privileges)
+                id_ = self._params.get_int_or_none('id')
+                if target_class.can_create_by_id:
+                    item = target_class.by_id_or_create(self.conn, id_)
+                else:
+                    item = target_class.by_id(self.conn, id_)
+                return f(self, item)
+            return wrapper
+        return decorator
+
     def do_GET_(self) -> str:
         """Return redirect target on GET /."""
         return '/day'
@@ -244,7 +320,7 @@ class TaskHandler(BaseHTTPRequestHandler):
     def do_GET_day(self) -> dict[str, object]:
         """Show single Day of ?date=."""
         date = self._params.get_str('date', date_in_n_days(0))
-        day = Day.by_id(self.conn, date, create=True)
+        day = Day.by_id_or_create(self.conn, date)
         make_type = self._params.get_str('make_type')
         conditions_present = []
         enablers_for = {}
@@ -270,7 +346,8 @@ class TaskHandler(BaseHTTPRequestHandler):
                 'conditions_present': conditions_present,
                 'processes': Process.all(self.conn)}
 
-    def do_GET_todo(self) -> dict[str, object]:
+    @_get_item(Todo)
+    def do_GET_todo(self, todo: Todo) -> dict[str, object]:
         """Show single Todo of ?id=."""
 
         @dataclass
@@ -321,8 +398,6 @@ class TaskHandler(BaseHTTPRequestHandler):
                 ids = ids | collect_adoptables_keys(node.children)
             return ids
 
-        id_ = self._params.get_int('id')
-        todo = Todo.by_id(self.conn, id_)
         todo_steps = [step.todo for step in todo.get_step_tree(set()).children]
         process_tree = todo.process.get_steps(self.conn, None)
         steps_todo_to_process: list[TodoStepsNode] = []
@@ -335,7 +410,8 @@ class TaskHandler(BaseHTTPRequestHandler):
         adoptables: dict[int, list[Todo]] = {}
         any_adoptables = [Todo.by_id(self.conn, t.id_)
                           for t in Todo.by_date(self.conn, todo.date)
-                          if t != todo]
+                          if t.id_ is not None
+                          and t != todo]
         for id_ in collect_adoptables_keys(steps_todo_to_process):
             adoptables[id_] = [t for t in any_adoptables
                                if t.process.id_ == id_]
@@ -358,22 +434,7 @@ class TaskHandler(BaseHTTPRequestHandler):
         todos = [t for t in todos_by_date_range
                  if comment_pattern in t.comment
                  and ((not process_id) or t.process.id_ == process_id)]
-        if sort_by == 'doneness':
-            todos.sort(key=lambda t: t.is_done)
-        elif sort_by == '-doneness':
-            todos.sort(key=lambda t: t.is_done, reverse=True)
-        elif sort_by == 'title':
-            todos.sort(key=lambda t: t.title_then)
-        elif sort_by == '-title':
-            todos.sort(key=lambda t: t.title_then, reverse=True)
-        elif sort_by == 'comment':
-            todos.sort(key=lambda t: t.comment)
-        elif sort_by == '-comment':
-            todos.sort(key=lambda t: t.comment, reverse=True)
-        elif sort_by == '-date':
-            todos.sort(key=lambda t: t.date, reverse=True)
-        else:
-            todos.sort(key=lambda t: t.date)
+        sort_by = Todo.sort_by(todos, sort_by)
         return {'start': start, 'end': end, 'process_id': process_id,
                 'comment_pattern': comment_pattern, 'todos': todos,
                 'all_processes': Process.all(self.conn), 'sort_by': sort_by}
@@ -381,24 +442,16 @@ class TaskHandler(BaseHTTPRequestHandler):
     def do_GET_conditions(self) -> dict[str, object]:
         """Show all Conditions."""
         pattern = self._params.get_str('pattern')
-        conditions = Condition.matching(self.conn, pattern)
         sort_by = self._params.get_str('sort_by')
-        if sort_by == 'is_active':
-            conditions.sort(key=lambda c: c.is_active)
-        elif sort_by == '-is_active':
-            conditions.sort(key=lambda c: c.is_active, reverse=True)
-        elif sort_by == '-title':
-            conditions.sort(key=lambda c: c.title.newest, reverse=True)
-        else:
-            conditions.sort(key=lambda c: c.title.newest)
+        conditions = Condition.matching(self.conn, pattern)
+        sort_by = Condition.sort_by(conditions, sort_by)
         return {'conditions': conditions,
                 'sort_by': sort_by,
                 'pattern': pattern}
 
-    def do_GET_condition(self) -> dict[str, object]:
+    @_get_item(Condition)
+    def do_GET_condition(self, c: Condition) -> dict[str, object]:
         """Show Condition of ?id=."""
-        id_ = self._params.get_int_or_none('id')
-        c = Condition.by_id(self.conn, id_, create=True)
         ps = Process.all(self.conn)
         return {'condition': c, 'is_new': c.id_ is None,
                 'enabled_processes': [p for p in ps if c in p.conditions],
@@ -406,31 +459,35 @@ class TaskHandler(BaseHTTPRequestHandler):
                 'enabling_processes': [p for p in ps if c in p.enables],
                 'disabling_processes': [p for p in ps if c in p.disables]}
 
-    def do_GET_condition_titles(self) -> dict[str, object]:
+    @_get_item(Condition)
+    def do_GET_condition_titles(self, c: Condition) -> dict[str, object]:
         """Show title history of Condition of ?id=."""
-        id_ = self._params.get_int_or_none('id')
-        condition = Condition.by_id(self.conn, id_)
-        return {'condition': condition}
+        return {'condition': c}
 
-    def do_GET_condition_descriptions(self) -> dict[str, object]:
+    @_get_item(Condition)
+    def do_GET_condition_descriptions(self, c: Condition) -> dict[str, object]:
         """Show description historys of Condition of ?id=."""
-        id_ = self._params.get_int_or_none('id')
-        condition = Condition.by_id(self.conn, id_)
-        return {'condition': condition}
+        return {'condition': c}
 
-    def do_GET_process(self) -> dict[str, object]:
+    @_get_item(Process)
+    def do_GET_process(self, process: Process) -> dict[str, object]:
         """Show Process of ?id=."""
-        id_ = self._params.get_int_or_none('id')
-        process = Process.by_id(self.conn, id_, create=True)
+        owner_ids = self._params.get_all_int('step_to')
+        owned_ids = self._params.get_all_int('has_step')
         title_64 = self._params.get_str('title_b64')
         if title_64:
-            title = b64decode(title_64.encode()).decode()
+            try:
+                title = b64decode(title_64.encode()).decode()
+            except binascii_Exception as exc:
+                msg = 'invalid base64 for ?title_b64='
+                raise BadFormatException(msg) from exc
             process.title.set(title)
+        preset_top_step = None
         owners = process.used_as_step_by(self.conn)
-        for step_id in self._params.get_all_int('step_to'):
+        for step_id in owner_ids:
             owners += [Process.by_id(self.conn, step_id)]
-        preset_top_step = None
-        for process_id in self._params.get_all_int('has_step'):
+        for process_id in owned_ids:
+            Process.by_id(self.conn, process_id)  # to ensure ID exists
             preset_top_step = process_id
         return {'process': process, 'is_new': process.id_ is None,
                 'preset_top_step': preset_top_step,
@@ -439,49 +496,57 @@ class TaskHandler(BaseHTTPRequestHandler):
                 'process_candidates': Process.all(self.conn),
                 'condition_candidates': Condition.all(self.conn)}
 
-    def do_GET_process_titles(self) -> dict[str, object]:
+    @_get_item(Process)
+    def do_GET_process_titles(self, p: Process) -> dict[str, object]:
         """Show title history of Process of ?id=."""
-        id_ = self._params.get_int_or_none('id')
-        process = Process.by_id(self.conn, id_)
-        return {'process': process}
+        return {'process': p}
 
-    def do_GET_process_descriptions(self) -> dict[str, object]:
+    @_get_item(Process)
+    def do_GET_process_descriptions(self, p: Process) -> dict[str, object]:
         """Show description historys of Process of ?id=."""
-        id_ = self._params.get_int_or_none('id')
-        process = Process.by_id(self.conn, id_)
-        return {'process': process}
+        return {'process': p}
 
-    def do_GET_process_efforts(self) -> dict[str, object]:
+    @_get_item(Process)
+    def do_GET_process_efforts(self, p: Process) -> dict[str, object]:
         """Show default effort history of Process of ?id=."""
-        id_ = self._params.get_int_or_none('id')
-        process = Process.by_id(self.conn, id_)
-        return {'process': process}
+        return {'process': p}
 
     def do_GET_processes(self) -> dict[str, object]:
         """Show all Processes."""
         pattern = self._params.get_str('pattern')
-        processes = Process.matching(self.conn, pattern)
         sort_by = self._params.get_str('sort_by')
-        if sort_by == 'steps':
-            processes.sort(key=lambda p: len(p.explicit_steps))
-        elif sort_by == '-steps':
-            processes.sort(key=lambda p: len(p.explicit_steps), reverse=True)
-        elif sort_by == 'owners':
-            processes.sort(key=lambda p: p.n_owners or 0)
-        elif sort_by == '-owners':
-            processes.sort(key=lambda p: p.n_owners or 0, reverse=True)
-        elif sort_by == 'effort':
-            processes.sort(key=lambda p: p.effort.newest)
-        elif sort_by == '-effort':
-            processes.sort(key=lambda p: p.effort.newest, reverse=True)
-        elif sort_by == '-title':
-            processes.sort(key=lambda p: p.title.newest, reverse=True)
-        else:
-            processes.sort(key=lambda p: p.title.newest)
+        processes = Process.matching(self.conn, pattern)
+        sort_by = Process.sort_by(processes, sort_by)
         return {'processes': processes, 'sort_by': sort_by, 'pattern': pattern}
 
     # POST handlers
 
+    @staticmethod
+    def _delete_or_post(target_class: Any, redir_target: str = '/'
+                        ) -> Callable[..., Callable[[TaskHandler], str]]:
+        def decorator(f: Callable[..., str]
+                      ) -> Callable[[TaskHandler], str]:
+            def wrapper(self: TaskHandler) -> str:
+                # pylint: disable=protected-access
+                # (because pylint here fails to detect the use of wrapper as a
+                # method to self with respective access privileges)
+                id_ = self._params.get_int_or_none('id')
+                for _ in self._form_data.get_all_str('delete'):
+                    if id_ is None:
+                        msg = 'trying to delete non-saved ' +\
+                                f'{target_class.__name__}'
+                        raise NotFoundException(msg)
+                    item = target_class.by_id(self.conn, id_)
+                    item.remove(self.conn)
+                    return redir_target
+                if target_class.can_create_by_id:
+                    item = target_class.by_id_or_create(self.conn, id_)
+                else:
+                    item = target_class.by_id(self.conn, id_)
+                return f(self, item)
+            return wrapper
+        return decorator
+
     def _change_versioned_timestamps(self, cls: Any, attr_name: str) -> str:
         """Update history timestamps for VersionedAttribute."""
         id_ = self._params.get_int_or_none('id')
@@ -492,50 +557,61 @@ class TaskHandler(BaseHTTPRequestHandler):
             if old[19:] != v:
                 attr.reset_timestamp(old, f'{v}.0')
         attr.save(self.conn)
-        cls_name = cls.__name__.lower()
-        return f'/{cls_name}_{attr_name}s?id={item.id_}'
+        return f'/{cls.name_lowercase()}_{attr_name}s?id={item.id_}'
 
     def do_POST_day(self) -> str:
         """Update or insert Day of date and Todos mapped to it."""
+        # pylint: disable=too-many-locals
         date = self._params.get_str('date')
-        day = Day.by_id(self.conn, date, create=True)
-        day.comment = self._form_data.get_str('day_comment')
-        day.save(self.conn)
+        day_comment = self._form_data.get_str('day_comment')
         make_type = self._form_data.get_str('make_type')
-        for process_id in sorted(self._form_data.get_all_int('new_todo')):
+        old_todos = self._form_data.get_all_int('todo_id')
+        new_todos = self._form_data.get_all_int('new_todo')
+        comments = self._form_data.get_all_str('comment')
+        efforts = self._form_data.get_all_floats_or_nones('effort')
+        done_todos = self._form_data.get_all_int('done')
+        for _ in [id_ for id_ in done_todos if id_ not in old_todos]:
+            raise BadFormatException('"done" field refers to unknown Todo')
+        is_done = [t_id in done_todos for t_id in old_todos]
+        if not (len(old_todos) == len(is_done) == len(comments)
+                == len(efforts)):
+            msg = 'not equal number each of number of todo_id, comments, ' +\
+                    'and efforts inputs'
+            raise BadFormatException(msg)
+        day = Day.by_id_or_create(self.conn, date)
+        day.comment = day_comment
+        day.save(self.conn)
+        for process_id in sorted(new_todos):
             if 'empty' == make_type:
                 process = Process.by_id(self.conn, process_id)
                 todo = Todo(None, process, False, date)
                 todo.save(self.conn)
             else:
                 Todo.create_with_children(self.conn, process_id, date)
-        done_ids = self._form_data.get_all_int('done')
-        comments = self._form_data.get_all_str('comment')
-        efforts = self._form_data.get_all_str('effort')
-        for i, todo_id in enumerate(self._form_data.get_all_int('todo_id')):
+        for i, todo_id in enumerate(old_todos):
             todo = Todo.by_id(self.conn, todo_id)
-            todo.is_done = todo_id in done_ids
-            if len(comments) > 0:
-                todo.comment = comments[i]
-            if len(efforts) > 0:
-                todo.effort = float(efforts[i]) if efforts[i] else None
+            todo.is_done = is_done[i]
+            todo.comment = comments[i]
+            todo.effort = efforts[i]
             todo.save(self.conn)
         return f'/day?date={date}&make_type={make_type}'
 
-    def do_POST_todo(self) -> str:
+    @_delete_or_post(Todo, '/')
+    def do_POST_todo(self, todo: Todo) -> str:
         """Update Todo and its children."""
         # pylint: disable=too-many-locals
-        # pylint: disable=too-many-branches
-        id_ = self._params.get_int('id')
-        for _ in self._form_data.get_all_str('delete'):
-            todo = Todo .by_id(self.conn, id_)
-            todo.remove(self.conn)
-            return '/'
-        todo = Todo.by_id(self.conn, id_)
         adopted_child_ids = self._form_data.get_all_int('adopt')
         processes_to_make_full = self._form_data.get_all_int('make_full')
         processes_to_make_empty = self._form_data.get_all_int('make_empty')
         fill_fors = self._form_data.get_first_strings_starting('fill_for_')
+        effort = self._form_data.get_str('effort', ignore_strict=True)
+        conditions = self._form_data.get_all_int('conditions')
+        disables = self._form_data.get_all_int('disables')
+        blockers = self._form_data.get_all_int('blockers')
+        enables = self._form_data.get_all_int('enables')
+        is_done = len(self._form_data.get_all_str('done')) > 0
+        calendarize = len(self._form_data.get_all_str('calendarize')) > 0
+        comment = self._form_data.get_str('comment', ignore_strict=True)
         for v in fill_fors.values():
             if v.startswith('make_empty_'):
                 processes_to_make_empty += [int(v[11:])]
@@ -564,16 +640,14 @@ class TaskHandler(BaseHTTPRequestHandler):
         for process_id in processes_to_make_full:
             made = Todo.create_with_children(self.conn, process_id, todo.date)
             todo.add_child(made)
-        effort = self._form_data.get_str('effort', ignore_strict=True)
         todo.effort = float(effort) if effort else None
-        todo.set_conditions(self.conn,
-                            self._form_data.get_all_int('condition'))
-        todo.set_blockers(self.conn, self._form_data.get_all_int('blocker'))
-        todo.set_enables(self.conn, self._form_data.get_all_int('enables'))
-        todo.set_disables(self.conn, self._form_data.get_all_int('disables'))
-        todo.is_done = len(self._form_data.get_all_str('done')) > 0
-        todo.calendarize = len(self._form_data.get_all_str('calendarize')) > 0
-        todo.comment = self._form_data.get_str('comment', ignore_strict=True)
+        todo.set_conditions(self.conn, conditions)
+        todo.set_blockers(self.conn, blockers)
+        todo.set_enables(self.conn, enables)
+        todo.set_disables(self.conn, disables)
+        todo.is_done = is_done
+        todo.calendarize = calendarize
+        todo.comment = comment
         todo.save(self.conn)
         return f'/todo?id={todo.id_}'
 
@@ -589,60 +663,70 @@ class TaskHandler(BaseHTTPRequestHandler):
         """Update history timestamps for Process.title."""
         return self._change_versioned_timestamps(Process, 'title')
 
-    def do_POST_process(self) -> str:
+    @_delete_or_post(Process, '/processes')
+    def do_POST_process(self, process: Process) -> str:
         """Update or insert Process of ?id= and fields defined in postvars."""
-        # pylint: disable=too-many-branches
-        id_ = self._params.get_int_or_none('id')
-        for _ in self._form_data.get_all_str('delete'):
-            process = Process.by_id(self.conn, id_)
-            process.remove(self.conn)
-            return '/processes'
-        process = Process.by_id(self.conn, id_, create=True)
-        process.title.set(self._form_data.get_str('title'))
-        process.description.set(self._form_data.get_str('description'))
-        process.effort.set(self._form_data.get_float('effort'))
-        process.set_conditions(self.conn,
-                               self._form_data.get_all_int('condition'))
-        process.set_blockers(self.conn, self._form_data.get_all_int('blocker'))
-        process.set_enables(self.conn, self._form_data.get_all_int('enables'))
-        process.set_disables(self.conn,
-                             self._form_data.get_all_int('disables'))
-        process.calendarize = self._form_data.get_all_str('calendarize') != []
+        # pylint: disable=too-many-locals
+        # pylint: disable=too-many-statements
+        title = self._form_data.get_str('title')
+        description = self._form_data.get_str('description')
+        effort = self._form_data.get_float('effort')
+        conditions = self._form_data.get_all_int('conditions')
+        blockers = self._form_data.get_all_int('blockers')
+        enables = self._form_data.get_all_int('enables')
+        disables = self._form_data.get_all_int('disables')
+        calendarize = self._form_data.get_all_str('calendarize') != []
+        suppresses = self._form_data.get_all_int('suppresses')
+        step_of = self._form_data.get_all_str('step_of')
+        keep_steps = self._form_data.get_all_int('keep_step')
+        step_ids = self._form_data.get_all_int('steps')
+        new_top_steps = self._form_data.get_all_str('new_top_step')
+        step_process_id_to = {}
+        step_parent_id_to = {}
+        new_steps_to = {}
+        for step_id in step_ids:
+            name = f'new_step_to_{step_id}'
+            new_steps_to[step_id] = self._form_data.get_all_int(name)
+        for step_id in keep_steps:
+            name = f'step_{step_id}_process_id'
+            step_process_id_to[step_id] = self._form_data.get_int(name)
+            name = f'step_{step_id}_parent_id'
+            step_parent_id_to[step_id] = self._form_data.get_int_or_none(name)
+        process.title.set(title)
+        process.description.set(description)
+        process.effort.set(effort)
+        process.set_conditions(self.conn, conditions)
+        process.set_blockers(self.conn, blockers)
+        process.set_enables(self.conn, enables)
+        process.set_disables(self.conn, disables)
+        process.calendarize = calendarize
         process.save(self.conn)
         assert isinstance(process.id_, int)
+        new_step_title = None
         steps: list[ProcessStep] = []
-        for step_id in self._form_data.get_all_int('keep_step'):
-            if step_id not in self._form_data.get_all_int('steps'):
+        for step_id in keep_steps:
+            if step_id not in step_ids:
                 raise BadFormatException('trying to keep unknown step')
-        for step_id in self._form_data.get_all_int('steps'):
-            if step_id not in self._form_data.get_all_int('keep_step'):
-                continue
-            step_process_id = self._form_data.get_int(
-                    f'step_{step_id}_process_id')
-            parent_id = self._form_data.get_int_or_none(
-                    f'step_{step_id}_parent_id')
-            steps += [ProcessStep(step_id, process.id_, step_process_id,
-                                  parent_id)]
-        for step_id in self._form_data.get_all_int('steps'):
-            for step_process_id in self._form_data.get_all_int(
-                    f'new_step_to_{step_id}'):
-                steps += [ProcessStep(None, process.id_, step_process_id,
-                                      step_id)]
-        new_step_title = None
-        for step_identifier in self._form_data.get_all_str('new_top_step'):
+            step = ProcessStep(step_id, process.id_,
+                               step_process_id_to[step_id],
+                               step_parent_id_to[step_id])
+            steps += [step]
+        for step_id in step_ids:
+            new = [ProcessStep(None, process.id_, step_process_id, step_id)
+                   for step_process_id in new_steps_to[step_id]]
+            steps += new
+        for step_identifier in new_top_steps:
             try:
                 step_process_id = int(step_identifier)
-                steps += [ProcessStep(None, process.id_, step_process_id,
-                                      None)]
+                step = ProcessStep(None, process.id_, step_process_id, None)
+                steps += [step]
             except ValueError:
                 new_step_title = step_identifier
         process.set_steps(self.conn, steps)
-        process.set_step_suppressions(self.conn,
-                                      self._form_data.
-                                      get_all_int('suppresses'))
+        process.set_step_suppressions(self.conn, suppresses)
         owners_to_set = []
         new_owner_title = None
-        for owner_identifier in self._form_data.get_all_str('step_of'):
+        for owner_identifier in step_of:
             try:
                 owners_to_set += [int(owner_identifier)]
             except ValueError:
@@ -666,16 +750,14 @@ class TaskHandler(BaseHTTPRequestHandler):
         """Update history timestamps for Condition.title."""
         return self._change_versioned_timestamps(Condition, 'title')
 
-    def do_POST_condition(self) -> str:
+    @_delete_or_post(Condition, '/conditions')
+    def do_POST_condition(self, condition: Condition) -> str:
         """Update/insert Condition of ?id= and fields defined in postvars."""
-        id_ = self._params.get_int_or_none('id')
-        for _ in self._form_data.get_all_str('delete'):
-            condition = Condition.by_id(self.conn, id_)
-            condition.remove(self.conn)
-            return '/conditions'
-        condition = Condition.by_id(self.conn, id_, create=True)
-        condition.is_active = self._form_data.get_all_str('is_active') != []
-        condition.title.set(self._form_data.get_str('title'))
-        condition.description.set(self._form_data.get_str('description'))
+        is_active = self._form_data.get_str('is_active') == 'True'
+        title = self._form_data.get_str('title')
+        description = self._form_data.get_str('description')
+        condition.is_active = is_active
+        condition.title.set(title)
+        condition.description.set(description)
         condition.save(self.conn)
         return f'/condition?id={condition.id_}'