#258 Removed DbNode from sqlalchemy models, Django model and dummy model

aiida/backends/djsite/db/models.py

@@ -129,12 +129,6 @@ class DbNode(m.Model):
 
     * A is 'input' of C.
     * C is 'output' of A.
-    * A is 'parent' of B,C
-    * C,B are 'children' of A.
-
-    :note: parents and children are stored in the DbPath table, the transitive
-      closure table, automatically updated via DB triggers whenever a link is
-      added to or removed from the DbLink table.
 
     Internal attributes, that define the node itself,
     are stored in the DbAttribute table; further user-defined attributes,
@@ -170,9 +164,6 @@ class DbNode(m.Model):
     # Direct links
     outputs = m.ManyToManyField('self', symmetrical=False,
                                 related_name='inputs', through='DbLink')
-    # Transitive closure
-    children = m.ManyToManyField('self', symmetrical=False,
-                                 related_name='parents', through='DbPath')
 
     # Used only if dbnode is a calculation, or remotedata
     # Avoid that computers can be deleted if at least a node exists pointing
@@ -305,50 +296,6 @@ def __str__(self):
             self.output.pk, )
 
 
-@python_2_unicode_compatible
-class DbPath(m.Model):
-    """
-    Transitive closure table for all dbnode paths.
-    """
-    parent = m.ForeignKey('DbNode', related_name='child_paths', editable=False)
-    child = m.ForeignKey('DbNode', related_name='parent_paths', editable=False)
-    depth = m.IntegerField(editable=False)
-
-    # Used to delete or to expand the path
-    entry_edge_id = m.IntegerField(null=True, editable=False)
-    direct_edge_id = m.IntegerField(null=True, editable=False)
-    exit_edge_id = m.IntegerField(null=True, editable=False)
-
-    def __str__(self):
-        return "{} ({}) ==[{}]==>> {} ({})".format(
-            self.parent.get_simple_name(invalid_result="Unknown node"),
-            self.parent.pk,
-            self.depth,
-            self.child.get_simple_name(invalid_result="Unknown node"),
-            self.child.pk, )
-
-    def expand(self):
-        """
-        Method to expand a DbPath (recursive function), i.e., to get a list
-        of all dbnodes that are traversed in the given path.
-
-        :return: list of DbNode objects representing the expanded DbPath
-        """
-
-        if self.depth == 0:
-            return [self.parent, self.child]
-        else:
-            path_entry = []
-            path_direct = DbPath.objects.get(id=self.direct_edge_id).expand()
-            path_exit = []
-            # we prevent DbNode repetitions
-            if self.entry_edge_id != self.direct_edge_id:
-                path_entry = DbPath.objects.get(id=self.entry_edge_id).expand()[:-1]
-            if self.exit_edge_id != self.direct_edge_id:
-                path_exit = DbPath.objects.get(id=self.exit_edge_id).expand()[1:]
-
-            return path_entry + path_direct + path_exit
-
 
 attrdatatype_choice = (
     ('float', 'float'),

aiida/backends/djsite/querybuilder_django/dummy_model.py

@@ -82,33 +82,6 @@ class DbLink(Base):
     output = relationship("DbNode", primaryjoin="DbLink.output_id == DbNode.id")
     label = Column(String(255), index=True, nullable=False)
 
-
-class DbPath(Base):
-    __tablename__ = "db_dbpath"
-    id = Column(Integer, primary_key=True)
-    parent_id = Column(
-        Integer,
-        ForeignKey('db_dbnode.id', deferrable=True, initially="DEFERRED")
-    )
-    child_id = Column(
-        Integer,
-        ForeignKey('db_dbnode.id', deferrable=True, initially="DEFERRED")
-    )
-    parent = relationship(
-        "DbNode",
-        primaryjoin="DbPath.parent_id == DbNode.id",
-        backref="child_paths"
-    )
-    child = relationship(
-        "DbNode",
-        primaryjoin="DbPath.child_id == DbNode.id",
-        backref="parent_paths"
-    )
-    depth = Column(Integer)
-    entry_edge_id = Column(Integer)
-    direct_edge_id = Column(Integer)
-    exit_edge_id = Column(Integer)
-
 class DbCalcState(Base):
     __tablename__ = "db_dbcalcstate"
     id = Column(Integer, primary_key=True)
@@ -320,13 +293,6 @@ class DbNode(Base):
         passive_deletes =   True
     )
 
-    children = relationship(
-        "DbNode",
-        secondary       =   "db_dbpath",
-        primaryjoin     =   "DbNode.id == DbPath.parent_id",
-        secondaryjoin   =   "DbNode.id == DbPath.child_id",
-        backref         =   "parents"
-    )
     def get_aiida_class(self):
         """
         Return the corresponding instance of

aiida/backends/djsite/querybuilder_django/querybuilder_django.py

@@ -23,7 +23,7 @@
 from sqlalchemy.orm import aliased
 from sqlalchemy.orm.attributes import InstrumentedAttribute
 
-from sqlalchemy.sql.expression import cast
+from sqlalchemy.sql.expression import cast, ColumnClause
 from sqlalchemy.sql.elements import Cast, Label
 from aiida.common.exceptions import InputValidationError
 from aiida.backends.general.querybuilder_interface import QueryBuilderInterface
@@ -104,7 +104,7 @@ def get_filter_expr_from_column(self, operator, value, column):
 
         # Label is used because it is what is returned for the
         # 'state' column by the hybrid_column construct
-        if not isinstance(column, (Cast, InstrumentedAttribute, Label)):
+        if not isinstance(column, (Cast, InstrumentedAttribute, Label, ColumnClause)):
             raise TypeError(
                 'column ({}) {} is not a valid column'.format(
                     type(column), column
@@ -282,14 +282,6 @@ def get_filter_expr(
         return expr
 
 
-
-
-    def prepare_with_dbpath(self):
-        #~ from aiida.backends.querybuild.dummy_model import DbPath as DummyPath
-        self.Path = dummy_model.DbPath
-
-
-
     def get_session(self):
         return dummy_model.get_aldjemy_session()
         # return dummy_model.session

aiida/backends/general/querybuilder_interface.py

@@ -90,18 +90,6 @@ def AiidaComputer(self):
         pass
 
     @abstractmethod
-    def prepare_with_dbpath(self):
-        """
-        A method to use the DbPath, if this is supported, or throw an
-        exception if not.
-        The overrider must fill add the DbPath-ORM as an attribute to self::
-
-            from aiida.backends.implementation.model import DbPath
-            self.path = DbPath
-
-        """
-        pass
-    @abstractmethod
     def get_session(self):
         """
         :returns: a valid session, an instance of sqlalchemy.orm.session.Session

aiida/backends/sqlalchemy/models/node.py

@@ -133,25 +133,6 @@ def outputs(self):
     def inputs(self):
         return self.inputs_q.all()
 
-    # children via db_dbpath
-    # suggest change name to descendants
-    children_q = relationship(
-        "DbNode", secondary="db_dbpath",
-        primaryjoin="DbNode.id == DbPath.parent_id",
-        secondaryjoin="DbNode.id == DbPath.child_id",
-        backref=backref("parents_q", passive_deletes=True, lazy='dynamic'),
-        lazy='dynamic',
-        passive_deletes=True
-    )
-
-    @property
-    def children(self):
-        return self.children_q.all()
-
-    @property
-    def parents(self):
-        return self.parents_q.all()
-
     def __init__(self, *args, **kwargs):
         super(DbNode, self).__init__(*args, **kwargs)
 
@@ -376,56 +357,3 @@ def __str__(self):
             self.output.pk
         )
 
-
-class DbPath(Base):
-    __tablename__ = "db_dbpath"
-
-    id = Column(Integer, primary_key=True)
-    parent_id = Column(
-        Integer,
-        ForeignKey('db_dbnode.id', deferrable=True, initially="DEFERRED")
-    )
-    child_id = Column(
-        Integer,
-        ForeignKey('db_dbnode.id', deferrable=True, initially="DEFERRED")
-    )
-
-    parent = relationship(
-        "DbNode",
-        primaryjoin="DbPath.parent_id == DbNode.id",
-        backref="child_paths"
-    )
-    child = relationship(
-        "DbNode",
-        primaryjoin="DbPath.child_id == DbNode.id",
-        backref="parent_paths"
-    )
-
-    depth = Column(Integer)
-
-    entry_edge_id = Column(Integer)
-    direct_edge_id = Column(Integer)
-    exit_edge_id = Column(Integer)
-
-    def expand(self):
-        """
-        Method to expand a DbPath (recursive function), i.e., to get a list
-        of all dbnodes that are traversed in the given path.
-
-        :return: list of DbNode objects representing the expanded DbPath
-        """
-
-        if self.depth == 0:
-            return [self.parent_id, self.child_id]
-        else:
-            path_entry = []
-            path_direct = DbPath.query.filter_by(id=self.direct_edge_id).first().expand()
-            path_exit = []
-            # we prevent DbNode repetitions
-            if self.entry_edge_id != self.direct_edge_id:
-                path_entry = DbPath.query.filter_by(id=self.entry_edge_id).first().expand()[:-1]
-            if self.exit_edge_id != self.direct_edge_id:
-                path_exit = DbPath.query.filter_by(id=self.exit_edge_id).first().expand()[1:]
-
-            return path_entry + path_direct + path_exit
-