IfcOpenShell API now supports port connections and disconnections.

src/ifcopenshell-python/ifcopenshell/api/system/connect_port.py

@@ -0,0 +1,122 @@
+# IfcOpenShell - IFC toolkit and geometry engine
+# Copyright (C) 2022 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of IfcOpenShell.
+#
+# IfcOpenShell is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# IfcOpenShell is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
+
+import ifcopenshell
+import ifcopenshell.api
+
+
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {
+            "port1": None,
+            "port2": None,
+            "direction": "NOTDEFINED",
+            "element": None,
+        }
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        # Note: there are a number of ambiguities with port connectivity. We
+        # assume system topology is represented by a directed graph. In other
+        # words, SOURCEANDSINK and NOTDEFINED implies a two way connection, with
+        # two IfcRelConnectsPorts. SOURCE or SINK by itself implies a one way
+        # connection. NOTDEFINED semantically implies that although you may
+        # traverse the graph either direction, the direction has not been
+        # determined yet by the engineer. None is not allowed as a direction as
+        # we assume None means that no connection is made.
+
+        if self.settings["port1"] == self.settings["port2"]:
+            return
+
+        self.purge_existing_connections_to_other_ports()
+
+        if self.settings["direction"] == "SOURCE":
+            self.settings["port1"].FlowDirection = "SOURCE"
+            self.settings["port2"].FlowDirection = "SINK"
+        elif self.settings["direction"] == "SINK":
+            self.settings["port1"].FlowDirection = "SINK"
+            self.settings["port2"].FlowDirection = "SOURCE"
+        else:
+            self.settings["port1"].FlowDirection = self.settings["direction"]
+            self.settings["port2"].FlowDirection = self.settings["direction"]
+
+        if self.settings["direction"] in ["SOURCE", "SOURCEANDSINK", "NOTDEFINED"]:
+            self.set_connected_to()
+        else:
+            self.purge_connected_to()
+
+        if self.settings["direction"] in ["SINK", "SOURCEANDSINK", "NOTDEFINED"]:
+            self.set_connected_from()
+        else:
+            self.purge_connected_from()
+
+        self.set_realising_element()
+
+    def purge_existing_connections_to_other_ports(self):
+        for rel in self.settings["port1"].ConnectedTo or []:
+            if rel.RelatedPort != self.settings["port2"]:
+                self.file.remove(rel)
+        for rel in self.settings["port1"].ConnectedFrom or []:
+            if rel.RelatingPort != self.settings["port2"]:
+                self.file.remove(rel)
+        for rel in self.settings["port2"].ConnectedTo or []:
+            if rel.RelatedPort != self.settings["port1"]:
+                self.file.remove(rel)
+        for rel in self.settings["port2"].ConnectedFrom or []:
+            if rel.RelatingPort != self.settings["port1"]:
+                self.file.remove(rel)
+
+    def set_connected_to(self):
+        if self.settings["port1"].ConnectedTo:
+            return
+
+        self.file.create_entity(
+            "IfcRelConnectsPorts",
+            GlobalId=ifcopenshell.guid.new(),
+            OwnerHistory=ifcopenshell.api.run("owner.create_owner_history", self.file),
+            RelatingPort=self.settings["port1"],
+            RelatedPort=self.settings["port2"],
+        )
+
+    def set_connected_from(self):
+        if self.settings["port1"].ConnectedFrom:
+            return
+
+        self.file.create_entity(
+            "IfcRelConnectsPorts",
+            GlobalId=ifcopenshell.guid.new(),
+            OwnerHistory=ifcopenshell.api.run("owner.create_owner_history", self.file),
+            RelatingPort=self.settings["port2"],
+            RelatedPort=self.settings["port1"],
+        )
+
+    def purge_connected_to(self):
+        for rel in self.settings["port1"].ConnectedTo or []:
+            self.file.remove(rel)
+
+    def purge_connected_from(self):
+        for rel in self.settings["port1"].ConnectedFrom or []:
+            self.file.remove(rel)
+
+    def set_realising_element(self):
+        for rel in self.settings["port1"].ConnectedTo or []:
+            rel.RealizingElement = self.settings["element"]
+        for rel in self.settings["port1"].ConnectedFrom or []:
+            rel.RealizingElement = self.settings["element"]

src/ifcopenshell-python/ifcopenshell/api/system/disconnect_port.py

@@ -0,0 +1,39 @@
+# IfcOpenShell - IFC toolkit and geometry engine
+# Copyright (C) 2022 Dion Moult <dion@thinkmoult.com>
+#
+# This file is part of IfcOpenShell.
+#
+# IfcOpenShell is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# IfcOpenShell is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with IfcOpenShell.  If not, see <http://www.gnu.org/licenses/>.
+
+import ifcopenshell
+import ifcopenshell.api
+
+
+class Usecase:
+    def __init__(self, file, **settings):
+        self.file = file
+        self.settings = {
+            "port": None,
+        }
+        for key, value in settings.items():
+            self.settings[key] = value
+
+    def execute(self):
+        rels = self.settings["port"].ConnectedTo or []
+        rels += self.settings["port"].ConnectedFrom or []
+
+        for rel in rels:
+            rel.RelatingPort.FlowDirection = None
+            rel.RelatedPort.FlowDirection = None
+            self.file.remove(rel)