gogo

design.d/cdrt-experiment.d/cdrt.py

@@ -0,0 +1,108 @@
+from yaml import safe_load as yaml_load
+from yaml import dump as yaml_dump
+from sys import argv
+
+def main():
+   path = "./testdata/hello_world.yaml"
+   if len(argv) > 1:
+      path = argv[1]
+   doc = Doc.from_file(path)
+   print(doc.render())
+   print(doc.to_dict())
+
+# https://blog.kevinjahns.de/are-crdts-suitable-for-shared-editing/
+class Doc():
+   def __init__(self):
+      self._nodes = []
+
+   def from_file(path):
+      doc = Doc()
+      with open(path, "r") as f:
+         d = yaml_load(f)
+         doc._nodes = [Node.from_dict(i) for i in d["nodes"]]
+      return doc
+
+   def to_dict(self):
+      return yaml_dump(slim_dict({
+         "nodes": [node.to_dict() for node in self._nodes],
+      }))
+
+   def render(self):
+      result = []
+      nodes = [node for node in self._nodes]
+      while nodes:
+         first = self._first_node(nodes)
+         result.append(first)
+         nodes = [node for node in nodes if node != first]
+      return "".join([i.content() for i in result])
+
+   def _first_node(self, nodes):
+      for potential_root_node in sorted([node for node in nodes if not node.from_id()], key=lambda x: x.id()):
+         return potential_root_node
+      node_ids = [node.id() for node in nodes]
+      for potential_rootest_node in sorted([node for node in nodes if not node.from_id() in node_ids], key=lambda x: x.id()):
+         return potential_rootest_node
+      raise Exception(nodes)
+
+class Node():
+   def __init__(self, client_name, ts, content, is_delete, from_id, to_id):
+      self._ts = ts
+      self._client_name = client_name
+      self._content = content
+      self._is_delete = is_delete
+      self._from_id = from_id
+      self._to_id = to_id
+
+   def __str__(self):
+      return str(self.to_dict())
+
+   def from_dict(d):
+      return Node(
+         d.get("client_name", ""),
+         d.get("ts", 0),
+         d.get("content", ""),
+         d.get("is_delete", False),
+         d.get("from", ""),
+         d.get("to", ""),
+      )
+
+   def to_dict(self):
+      return slim_dict({
+         "client_name": self._client_name,
+         "ts": self._ts,
+         "content": self._content,
+         "is_delete": self._is_delete,
+         "from": self._from_id,
+         "to": self._to_id,
+      })
+
+   def clone(self):
+      return Node(
+         self._ts,
+         self._client_name,
+         self._content,
+         self._is_delete,
+         self._from_id,
+         self._to_id,
+      )
+
+   def id(self):
+      return f'{self._ts}/{self._client_name}'
+
+   def from_id(self):
+      return self._from_id
+
+   def to_id(self):
+      return self._to_id
+
+   def content(self):
+      if self._is_delete:
+         self._content = ""
+      return self._content
+
+def slim_dict(d):
+   return {k:v for k,v in d.items() if v or (isinstance(v, int) and not isinstance(v, bool))}
+
+if __name__ == "__main__":
+   main()
+