schema: Continue

Signed-off-by: Jan Lindemann <jan@janware.com>

tools/python/jwutils/db/schema/Column.py

@@ -20,10 +20,27 @@ class Column(abc.ABC): # export
         self.__default_value_cached: bool = False
         self.__is_auto_increment: Optional[bool] = None
         self.__data_type: DataType = data_type
+        self.__foreign_keys: Optional[Any] = None
+        self.__foreign_keys_cached: bool = False
+        self.__foreign_keys_by_table: Optional[dict[str, Any]] = None
 
     def __repr__(self):
         return f'{self.__table.name}.{self.__name}: {self.__data_type}'
 
+    def __eq__(self, rhs) -> bool:
+        if isinstance(rhs, Column):
+            if self.__table != rhs.__table:
+                return False
+            if self.__name != rhs.__name:
+                return False
+            return True
+        elif isinstance(rhs, str):
+            if self.__name != rhs:
+                return False
+            return True
+        throw(ERR, f'Tried to compare column {self} to type {type(rhs)}: {rhs}')
+        return False # Unreachable but requested by mypy
+
     @property
     def name(self) -> str:
         return self.__name
@@ -73,3 +90,25 @@ class Column(abc.ABC): # export
             self.__default_value = self.__table.column_default(self.name)
             self.__default_value_cached = True
         return self.__default_value
+
+    # Returns Column object on parent table
+    @property
+    def foreign_keys(self) -> Optional[Any]:
+        if not self.__foreign_keys_cached:
+            fks: list[Any] = []
+            for cfk in self.__table.foreign_key_constraints:
+                for fk in cfk:
+                    if fk.child_column == self:
+                        fks.append(fk.parent_column)
+            self.__foreign_keys_cached = True
+            self.__foreign_keys = fks if fks else None
+        return self.__foreign_keys
+
+    def foreign_key(self, table) -> Optional[Any]:
+        if self.__foreign_keys_by_table is None:
+            self.__foreign_keys_by_table = dict()
+            for col in self.foreign_keys: # type: ignore # Any not iterable
+                assert(col.table.name not in self.__foreign_keys_by_table)
+                self.__foreign_keys_by_table[col.table.name] = col
+        table_name = table if isinstance(table, str) else table.name
+        return self.__foreign_keys_by_table.get(table_name)

tools/python/jwutils/db/schema/ColumnSet.py

@@ -1,11 +1,11 @@
 # -*- coding: utf-8 -*-
 
-from typing import Optional, List, Iterable, Any
+from typing import Optional, Iterable, Any
 
 class ColumnSet: # export
 
-    def __init__(self, *args: List[Any], columns: List[Any]=[], table: Optional[Any]=None, names: Optional[List[str]]=None):
-        self.__columns: List[Any] = [*args]
+    def __init__(self, *args: list[Any], columns: list[Any]=[], table: Optional[Any]=None, names: Optional[list[str]]=None):
+        self.__columns: list[Any] = [*args]
         self.__columns.extend(columns)
         self.__table = table
         if names is not None:
@@ -39,5 +39,5 @@ class ColumnSet: # export
         return True
 
     @property
-    def columns(self) -> List[Any]:
+    def columns(self) -> list[Any]:
         return self.__columns

tools/python/jwutils/db/schema/CompositeForeignKey.py

@@ -1,6 +1,8 @@
 # -*- coding: utf-8 -*-
 
-from typing import Optional, List, Any
+from typing import Optional, Any
+
+from jwutils.log import *
 
 from .ColumnSet import ColumnSet
 from .SingleForeignKey import SingleForeignKey
@@ -26,7 +28,9 @@ class CompositeForeignKey: # export
 
         assert(len(self.__child_col_set) == len(self.__parent_col_set))
         self.__len = len(self.__child_col_set)
-        self.__column_relations: Optional[List[SingleForeignKey]] = None
+        self.__column_relations: Optional[list[SingleForeignKey]] = None
+        self.__parent_columns_by_child_column: Optional[dict[str, Column]] = None
+        self.__child_columns_by_parent_column: Optional[dict[str, Column]] = None
 
     def __table_rel_str(self):
         return f'{self.__child_table.name} => {self.__parent_table.name}'
@@ -42,7 +46,7 @@ class CompositeForeignKey: # export
 
     def __repr__(self):
         ret = self.__table_rel_str()
-        ret += '|| ' + ' | '.join([self.__cols_rel_str(rel.child_col, rel.parent_col) for rel in self.column_relations])
+        ret += ': ' + ', '.join([self.__cols_rel_str(rel.child_column, rel.parent_column) for rel in self.column_relations])
         return ret
 
     def __eq__(self, rhs):
@@ -68,8 +72,29 @@ class CompositeForeignKey: # export
     def parent_columns(self) -> ColumnSet:
         return self.__parent_col_set
 
+    def parent_column(self, child_column):
+        child_column_name = child_column if isinstance(child_column, str) else child_column.name
+        if self.__parent_columns_by_child_column is None:
+            d: dict[str, Column] = {}
+            assert(len(self.__child_col_set) == len(self.__parent_col_set))
+            for i in range(0, len(self.__child_col_set)):
+                d[self.__child_col_set[i].name] = self.__parent_col_set[i]
+            self.__parent_columns_by_child_column = d
+        return self.__parent_columns_by_child_column[child_column]
+
+    def child_column(self, parent_column):
+        slog(WARNING, f'{self}: Looking for child column belonging to parent column "{parent_column}"')
+        parent_column_name = parent_column if isinstance(parent_column, str) else parent_column.name
+        if self.__child_columns_by_parent_column is None:
+            d: dict[str, Column] = {}
+            assert(len(self.__parent_col_set) == len(self.__child_col_set))
+            for i in range(0, len(self.__parent_col_set)):
+                d[self.__parent_col_set[i].name] = self.__child_col_set[i]
+            self.__child_columns_by_parent_column = d
+        return self.__child_columns_by_parent_column[parent_column]
+
     @property
-    def column_relations(self) -> List[Any]:
+    def column_relations(self) -> list[Any]:
         ret = []
         if self.__column_relations is None:
             for i in range(0, self.__len):

tools/python/jwutils/db/schema/DataType.py

@@ -48,12 +48,20 @@ class DataType: # export
             assert(size > 0)
         self.__id = type_id
         self.__size = size
+
     def __repr__(self):
-        ret = f'{self.__id}'
+        ret = f'{self.__id.name}'
         if self.__size is not None:
             ret += f'({self.__size})'
         return ret
 
+    def __eq__(self, rhs):
+        if self.__id != rhs.__id:
+            return False
+        if self.__size != rhs.__size:
+            return False
+        return True
+
     @property
     def type_id(self) -> Id:
         return self.__id

tools/python/jwutils/db/schema/Schema.py

@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 
-from typing import Optional, List, Iterable
+from typing import Optional, Iterable
 
 import abc
 
@@ -14,16 +14,16 @@ from .CompositeForeignKey import CompositeForeignKey
 class Schema(abc.ABC): # export
 
     def __init__(self) -> None:
-        self.___tables: Optional[List[Table]] = None
-        self.__foreign_keys: Optional[List[CompositeForeignKey]] = None
-        self.__access_defining_columns: Optional[List[str]] = None
+        self.___tables: Optional[list[Table]] = None
+        self.__foreign_keys: Optional[list[CompositeForeignKey]] = None
+        self.__access_defining_columns: Optional[list[str]] = None
 
     @property
     def __tables(self):
         if self.___tables is None:
             ret = dict()
             for name in self._table_names():
-                slog(WARNING, f'Caching metadata for table "{name}"')
+                slog(DEBUG, f'Caching metadata for table "{name}"')
                 assert(isinstance(name, str))
                 ret[name] = self._table(name)
             self.___tables = ret
@@ -42,7 +42,7 @@ class Schema(abc.ABC): # export
         return None # type: ignore
 
     @abc.abstractmethod
-    def _foreign_keys(self) -> List[CompositeForeignKey]:
+    def _foreign_keys(self) -> list[CompositeForeignKey]:
         pass
 
     @abc.abstractmethod
@@ -51,6 +51,18 @@ class Schema(abc.ABC): # export
 
     # ------ API to be called
 
+    def __len__(self):
+        return len(self.__tables)
+
+    def __iter__(self):
+        yield from self.__tables.values()
+
+    def __repr__(self):
+        return '|'.join([table.name for table in self.__tables])
+
+    def __getitem__(self, index):
+        return self.__tables[index]
+
     @property
     def table_names(self) -> Iterable[str]:
         return self.__tables.keys()
@@ -66,7 +78,7 @@ class Schema(abc.ABC): # export
         return self.__access_defining_columns
 
     @property
-    def foreign_key_constraints(self) -> List[CompositeForeignKey]:
+    def foreign_key_constraints(self) -> list[CompositeForeignKey]:
         if self.__foreign_keys is None:
             self.__foreign_keys = self._foreign_keys()
         return self.__foreign_keys

tools/python/jwutils/db/schema/SingleForeignKey.py

@@ -1,19 +1,33 @@
 # -*- coding: utf-8 -*-
 
-from typing import Optional, List, Any
+from typing import Optional, Any
 
+from .Column import Column
 from .ColumnSet import ColumnSet
 
 class SingleForeignKey:
 
-    def __init__(self, child_col, parent_col):
+    def __init__(self, child_col: Column, parent_col: Column):
         self.__child_col = child_col
         self.__parent_col = parent_col
+        self.__iterable = (self.__child_col, self.__parent_col)
+
+    def __len__(self):
+        return 2
+
+    def __iter__(self):
+        yield from self.__iterable
+
+    def __repr__(self):
+        return f'{self.__child_col.table.name}.{self.__child_col.name} -> {self.__parent_col.table.name}.{self.__parent_col.name}'
+
+    def __getitem__(self, index):
+        return self.__iterable[index]
 
     @property
-    def child_col(self):
+    def child_column(self):
         return self.__child_col
 
     @property
-    def parent_col(self):
+    def parent_column(self):
         return self.__parent_col

tools/python/jwutils/db/schema/Table.py

@@ -1,6 +1,6 @@
 # -*- coding: utf-8 -*-
 
-from typing import Optional, Iterable, List, Any # TODO: Need any for many things, as I can't figure out how to avoid circular imports from here
+from typing import Optional, Iterable, Any # TODO: Need any for many things, as I can't figure out how to avoid circular imports from here
 
 import abc
 from collections import OrderedDict
@@ -18,26 +18,27 @@ class Table(abc.ABC): # export
         assert(isinstance(name, str))
         self.__schema = schema
         self.__name = name
-        self.__primary_keys: Optional[Iterable[str]] = None
-        self.__unique_constraints: Optional[List[ColumnSet]] = None
-        self.__foreign_key_constraints: Optional[List[CompositeForeignKey]] = None
+
         self.___columns: Optional[OrderedDict[str, Any]] = None
+        self.___foreign_key_parent_tables: Optional[OrderedDict[str, Any]]  = None
+
+        self.__primary_keys: Optional[Iterable[str]] = None
+        self.__unique_constraints: Optional[list[ColumnSet]] = None
+        self.__foreign_key_constraints: Optional[list[CompositeForeignKey]] = None
         self.__nullable_columns: Optional[Iterable[str]]  = None
         self.__non_nullable_columns: Optional[Iterable[str]]  = None
         self.__null_insertible_columns: Optional[Iterable[str]]  = None
         self.__not_null_insertible_columns: Optional[Iterable[str]]  = None
         self.__log_columns: Optional[Iterable[str]]  = None
+        self.__display_columns: Optional[Iterable[str]]  = None
         self.__column_default: Optional[dict[str, Any]]  = None
-
         self.__base_location: Optional[Iterable[str]]  = None
         self.__location: Optional[Iterable[str]]  = None
         self.__row_location: Optional[Iterable[str]]  = None
-
-    def __repr__(self) -> str:
-        return self.__name
+        self.__foreign_keys_to_parent_table: Optional[OrderedDict[str, Any]] = None
 
     @property
-    def __columns(self):
+    def __columns(self) -> OrderedDict[str, Any]:
         if self.___columns is None:
             ret: OrderedDict[str, Any] = OrderedDict()
             for name in self._column_names():
@@ -45,16 +46,47 @@ class Table(abc.ABC): # export
             self.___columns = ret
         return self.___columns
 
+    @property
+    def __foreign_key_parent_tables(self) -> OrderedDict[str, Any]:
+        if self.___foreign_key_parent_tables is None:
+            self.___foreign_key_parent_tables = OrderedDict()
+            for cfk in self.foreign_key_constraints:
+                self.___foreign_key_parent_tables[cfk.parent_table.name] = cfk.parent_table
+        return self.___foreign_key_parent_tables
+
+    def __len__(self):
+        return len(self.__columns)
+
+    def __iter__(self):
+        yield from self.__columns.values()
+
+    def __repr__(self) -> str:
+        return self.__name
+
+    def __getitem__(self, index):
+        return self.__columns[index]
+
+    def __eq__(self, rhs) -> bool:
+        if isinstance(rhs, Table):
+            if self.__name != rhs.__name:
+                return False
+            return True
+        elif isinstance(rhs, str):
+            if self.__name != rhs:
+                return False
+            return True
+        throw(ERR, f'Tried to compare table {self} to type {type(rhs)}: {rhs}')
+        return False # Unreachable but requested by mypy
+
+    def __hash__(self) -> int:
+        return hash(self.name)
+
     # -- To be reimplemented
 
     @abc.abstractmethod
     def _column_names(self) -> Iterable[str]:
         pass
 
-    @abc.abstractmethod
-    def _log_columns(self) -> Iterable[str]:
-        pass
-
     @abc.abstractmethod
     def _column_data_type(self, name) -> DataType:
         pass
@@ -63,6 +95,18 @@ class Table(abc.ABC): # export
     def _primary_keys(self) -> Iterable[str]:
         pass
 
+    @abc.abstractmethod
+    def _log_columns(self) -> Iterable[str]:
+        pass
+
+    @abc.abstractmethod
+    def _display_columns(self) -> Iterable[str]:
+        return self._primary_keys()
+
+    @abc.abstractmethod
+    def _nullable_columns(self) -> Iterable[str]:
+        pass
+
     @abc.abstractmethod
     def _auto_increment_columns(self) -> Iterable[str]:
         pass
@@ -72,7 +116,7 @@ class Table(abc.ABC): # export
         pass
 
     @abc.abstractmethod
-    def _unique_constraints(self) -> List[List[str]]:
+    def _unique_constraints(self) -> list[list[str]]:
         pass
 
     def _model_name(self) -> Optional[str]:
@@ -84,9 +128,13 @@ class Table(abc.ABC): # export
         throw(ERR, "Not implemented")
         return None
 
+    @abc.abstractmethod
+    def _query_name(self) -> str:
+        return self.__name
+
     # -- common URL schema for all data
     def _base_location(self) -> Optional[str]:
-        return f'/self.name'
+        return f'/{self.name}'
 
     def _location(self) -> Optional[str]:
         ret = ''
@@ -98,9 +146,10 @@ class Table(abc.ABC): # export
 
     def _row_location(self) -> Optional[str]:
         ret = self._location()
-        for col in self.primary_keys:
-            if col not in self.__schema.access_defining_columns:
-                ret += f'/<{col}>'
+        if ret is not None:
+            for col in self.primary_keys:
+                if col not in self.__schema.access_defining_columns:
+                    ret += f'/<{col}>'
         return ret
 
     # -- To be used
@@ -136,6 +185,9 @@ class Table(abc.ABC): # export
     def model_name(self) -> Optional[str]:
         return self._model_name()
 
+    def query_name(self) -> str:
+        return self._query_name()
+
     @property
     def base_location(self):
         if self.__base_location is None:
@@ -160,6 +212,22 @@ class Table(abc.ABC): # export
             self.__primary_keys = self._primary_keys()
         return self.__primary_keys
 
+    @property
+    def log_columns(self):
+        if self.__log_columns is None:
+            self.__log_columns = self._log_columns()
+        return self.__log_columns
+
+    @property
+    def display_columns(self):
+        if self.__display_columns is None:
+            self.__display_columns = self._display_columns()
+        return self.__display_columns
+
+    @property
+    def auto_increment_columns(self) -> Iterable[str]:
+        return self._auto_increment_columns()
+
     @property
     def nullable_columns(self) -> Iterable[str]:
         if self.__nullable_columns is None:
@@ -199,19 +267,9 @@ class Table(abc.ABC): # export
         return self.__not_null_insertible_columns
 
     @property
-    def log_columns(self):
-        if self.__log_columns is None:
-            self.__log_columns = self._log_columns()
-        return self.__log_columns
-
-    @property
-    def auto_increment_columns(self) -> Iterable[str]:
-        return self._auto_increment_columns()
-
-    @property
-    def unique_constraints(self) -> List[ColumnSet]:
+    def unique_constraints(self) -> list[ColumnSet]:
         if self.__unique_constraints is None:
-            ret: List[ColumnSet] = []
+            ret: list[ColumnSet] = []
             impl = self._unique_constraints()
             if impl is not None:
                 for columns in impl:
@@ -220,11 +278,26 @@ class Table(abc.ABC): # export
         return self.__unique_constraints
 
     @property
-    def foreign_key_constraints(self) -> List[CompositeForeignKey]:
+    def foreign_key_constraints(self) -> list[CompositeForeignKey]:
         if self.__foreign_key_constraints is None:
-            ret: List[Any] = []
+            ret: list[Any] = []
             for composite_key in self.__schema.foreign_key_constraints:
                 if composite_key.child_table == self:
                     ret.append(composite_key)
             self.__foreign_key_constraints = ret
         return self.__foreign_key_constraints
+
+    @property
+    def foreign_key_parent_tables(self):
+        return self.__foreign_key_parent_tables.values()
+
+    def foreign_keys_to_parent_table(self, parent_table) -> Iterable[CompositeForeignKey]:
+        if self.__foreign_keys_to_parent_table is None:
+            self.__foreign_keys_to_parent_table = OrderedDict()
+            for cfk in self.foreign_key_constraints:
+                pt = cfk.parent_table.name
+                if pt not in self.__foreign_keys_to_parent_table:
+                    self.__foreign_keys_to_parent_table[pt] = []
+                self.__foreign_keys_to_parent_table[pt].append(cfk)
+        parent_table_name = parent_table if isinstance(parent_table, str) else parent_table.name
+        return self.__foreign_keys_to_parent_table[parent_table_name]