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Improve readability of POST /todo code.
[plomtask] / plomtask / db.py
index b3f1db00986b1142f5f31be34060864840ab5bdc..67a7fc766ce607095520e174c944f957667011d7 100644 (file)
@@ -4,7 +4,7 @@ from os import listdir
 from os.path import isfile
 from difflib import Differ
 from sqlite3 import connect as sql_connect, Cursor, Row
-from typing import Any, Self, TypeVar, Generic
+from typing import Any, Self, TypeVar, Generic, Callable
 from plomtask.exceptions import HandledException, NotFoundException
 from plomtask.dating import valid_date
 
@@ -232,14 +232,16 @@ BaseModelInstance = TypeVar('BaseModelInstance', bound='BaseModel[Any]')
 class BaseModel(Generic[BaseModelId]):
     """Template for most of the models we use/derive from the DB."""
     table_name = ''
-    to_save: list[str] = []
-    to_save_versioned: list[str] = []
+    to_save_simples: list[str] = []
     to_save_relations: list[tuple[str, str, str, int]] = []
+    versioned_defaults: dict[str, str | float] = {}
+    add_to_dict: list[str] = []
     id_: None | BaseModelId
     cache_: dict[BaseModelId, Self]
     to_search: list[str] = []
     can_create_by_id = False
     _exists = True
+    sorters: dict[str, Callable[..., Any]] = {}
 
     def __init__(self, id_: BaseModelId | None) -> None:
         if isinstance(id_, int) and id_ < 1:
@@ -251,11 +253,12 @@ class BaseModel(Generic[BaseModelId]):
         self.id_ = id_
 
     def __hash__(self) -> int:
-        hashable = [self.id_] + [getattr(self, name) for name in self.to_save]
+        hashable = [self.id_] + [getattr(self, name)
+                                 for name in self.to_save_simples]
         for definition in self.to_save_relations:
             attr = getattr(self, definition[2])
             hashable += [tuple(rel.id_ for rel in attr)]
-        for name in self.to_save_versioned:
+        for name in self.to_save_versioned():
             hashable += [hash(getattr(self, name))]
         return hash(tuple(hashable))
 
@@ -272,59 +275,61 @@ class BaseModel(Generic[BaseModelId]):
         assert isinstance(other.id_, int)
         return self.id_ < other.id_
 
+    @classmethod
+    def to_save_versioned(cls) -> list[str]:
+        """Return keys of cls.versioned_defaults assuming we wanna save 'em."""
+        return list(cls.versioned_defaults.keys())
+
     @property
-    def as_dict(self) -> dict[str, object]:
-        """Return self as (json.dumps-compatible) dict."""
-        library: dict[str, dict[str | int, object]] = {}
-        d: dict[str, object] = {'id': self.id_, '_library': library}
-        for to_save in self.to_save:
-            attr = getattr(self, to_save)
-            if hasattr(attr, 'as_dict_into_reference'):
-                d[to_save] = attr.as_dict_into_reference(library)
-            else:
-                d[to_save] = attr
-        if len(self.to_save_versioned) > 0:
+    def as_dict_and_refs(self) -> tuple[dict[str, object],
+                                        list[BaseModel[int] | BaseModel[str]]]:
+        """Return self as json.dumps-ready dict, list of referenced objects."""
+        d: dict[str, object] = {'id': self.id_}
+        refs: list[BaseModel[int] | BaseModel[str]] = []
+        for to_save in self.to_save_simples:
+            d[to_save] = getattr(self, to_save)
+        if len(self.to_save_versioned()) > 0:
             d['_versioned'] = {}
-        for k in self.to_save_versioned:
+        for k in self.to_save_versioned():
             attr = getattr(self, k)
             assert isinstance(d['_versioned'], dict)
             d['_versioned'][k] = attr.history
-        for r in self.to_save_relations:
-            attr_name = r[2]
-            l: list[int | str] = []
-            for rel in getattr(self, attr_name):
-                l += [rel.as_dict_into_reference(library)]
-            d[attr_name] = l
-        return d
-
-    def as_dict_into_reference(self,
-                               library: dict[str, dict[str | int, object]]
-                               ) -> int | str:
-        """Return self.id_ while writing .as_dict into library."""
-        def into_library(library: dict[str, dict[str | int, object]],
-                         cls_name: str,
-                         id_: str | int,
-                         d: dict[str, object]
-                         ) -> None:
-            if cls_name not in library:
-                library[cls_name] = {}
-            if id_ in library[cls_name]:
-                if library[cls_name][id_] != d:
-                    msg = 'Unexpected inequality of entries for ' +\
-                            f'_library at: {cls_name}/{id_}'
-                    raise HandledException(msg)
-            else:
-                library[cls_name][id_] = d
-        as_dict = self.as_dict
-        assert isinstance(as_dict['_library'], dict)
-        for cls_name, dict_of_objs in as_dict['_library'].items():
-            for id_, obj in dict_of_objs.items():
-                into_library(library, cls_name, id_, obj)
-        del as_dict['_library']
-        assert self.id_ is not None
-        into_library(library, self.__class__.__name__, self.id_, as_dict)
-        assert isinstance(as_dict['id'], (int, str))
-        return as_dict['id']
+        rels_to_collect = [rel[2] for rel in self.to_save_relations]
+        rels_to_collect += self.add_to_dict
+        for attr_name in rels_to_collect:
+            rel_list = []
+            for item in getattr(self, attr_name):
+                rel_list += [item.id_]
+                if item not in refs:
+                    refs += [item]
+            d[attr_name] = rel_list
+        return d, refs
+
+    @classmethod
+    def name_lowercase(cls) -> str:
+        """Convenience method to return cls' name in lowercase."""
+        return cls.__name__.lower()
+
+    @classmethod
+    def sort_by(cls, seq: list[Any], sort_key: str, default: str = 'title'
+                ) -> str:
+        """Sort cls list by cls.sorters[sort_key] (reverse if '-'-prefixed).
+
+        Before cls.sorters[sort_key] is applied, seq is sorted by .id_, to
+        ensure predictability where parts of seq are of same sort value.
+        """
+        reverse = False
+        if len(sort_key) > 1 and '-' == sort_key[0]:
+            sort_key = sort_key[1:]
+            reverse = True
+        if sort_key not in cls.sorters:
+            sort_key = default
+        seq.sort(key=lambda x: x.id_, reverse=reverse)
+        sorter: Callable[..., Any] = cls.sorters[sort_key]
+        seq.sort(key=sorter, reverse=reverse)
+        if reverse:
+            sort_key = f'-{sort_key}'
+        return sort_key
 
     # cache management
     # (we primarily use the cache to ensure we work on the same object in
@@ -412,7 +417,7 @@ class BaseModel(Generic[BaseModelId]):
         """Make from DB row (sans relations), update DB cache with it."""
         obj = cls(*row)
         assert obj.id_ is not None
-        for attr_name in cls.to_save_versioned:
+        for attr_name in cls.to_save_versioned():
             attr = getattr(obj, attr_name)
             table_name = attr.table_name
             for row_ in db_conn.row_where(table_name, 'parent', obj.id_):
@@ -481,7 +486,7 @@ class BaseModel(Generic[BaseModelId]):
                                   date_col: str = 'day'
                                   ) -> tuple[list[BaseModelInstance], str,
                                              str]:
-        """Return list of items in database within (open) date_range interval.
+        """Return list of items in DB within (closed) date_range interval.
 
         If no range values provided, defaults them to 'yesterday' and
         'tomorrow'. Knows to properly interpret these and 'today' as value.
@@ -523,7 +528,7 @@ class BaseModel(Generic[BaseModelId]):
         """Write self to DB and cache and ensure .id_.
 
         Write both to DB, and to cache. To DB, write .id_ and attributes
-        listed in cls.to_save[_versioned|_relations].
+        listed in cls.to_save_[simples|versioned|_relations].
 
         Ensure self.id_ by setting it to what the DB command returns as the
         last saved row's ID (cursor.lastrowid), EXCEPT if self.id_ already
@@ -531,14 +536,14 @@ class BaseModel(Generic[BaseModelId]):
         only the case with the Day class, where it's to be a date string.
         """
         values = tuple([self.id_] + [getattr(self, key)
-                                     for key in self.to_save])
+                                     for key in self.to_save_simples])
         table_name = self.table_name
         cursor = db_conn.exec_on_vals(f'REPLACE INTO {table_name} VALUES',
                                       values)
         if not isinstance(self.id_, str):
             self.id_ = cursor.lastrowid  # type: ignore[assignment]
         self.cache()
-        for attr_name in self.to_save_versioned:
+        for attr_name in self.to_save_versioned():
             getattr(self, attr_name).save(db_conn)
         for table, column, attr_name, key_index in self.to_save_relations:
             assert isinstance(self.id_, (int, str))
@@ -550,7 +555,7 @@ class BaseModel(Generic[BaseModelId]):
         """Remove from DB and cache, including dependencies."""
         if self.id_ is None or self._get_cached(self.id_) is None:
             raise HandledException('cannot remove unsaved item')
-        for attr_name in self.to_save_versioned:
+        for attr_name in self.to_save_versioned():
             getattr(self, attr_name).remove(db_conn)
         for table, column, attr_name, _ in self.to_save_relations:
             db_conn.delete_where(table, column, self.id_)