1 files changed, 47 insertions, 0 deletions
diff --git a/interfaces.py b/interfaces.py
new file mode 100644
index 0000000..e0a904a
--- /dev/null
+++ b/interfaces.py
@@ -0,0 +1,47 @@
+"""Module containing various interfaces."""
+
+from abc import ABCMeta, abstractmethod, abstractclassmethod
+import xml.etree.ElementTree as et
+
+class XMLSerializable(metaclass=ABCMeta):
+    """Interface for XML-serializable Workspace components."""
+    @staticmethod
+    def int_or_none(v):
+        if v is None: 
+            return None
+
+        try:
+            v = int(v)
+        except (ValueError, TypeError):
+            return None
+
+        return v
+
+    @staticmethod
+    def indent(elem, indent=4, level=0):
+        """Pretty-indent the XML tree."""
+        i = "\n" + level*(indent*' ')
+        if len(elem) > 0:
+            if not elem.text or not elem.text.strip():
+                elem.text = i + (' '*indent)
+            if not elem.tail or not elem.tail.strip():
+                elem.tail = i
+            for elem in elem:
+                XMLSerializable.indent(elem, indent=indent, level=level+1)
+            if not elem.tail or not elem.tail.strip():
+                elem.tail = i
+        else:
+            if level and (not elem.tail or not elem.tail.strip()):
+                elem.tail = i
+
+    @abstractmethod
+    def serialize(self) -> et.Element:
+        """Serialize the object into an XML element."""
+
+    @abstractclassmethod
+    def deserialize(cls, w: "Workspace", e: et.Element):
+        """Deserialize the object from an XML element.
+        
+        This function may assume that all dependencies have already been loaded into the 
+        passed workspace.
+        """