feat: Add graph metrics getter in graph db interface and adapters [COG-1082] (#483)

Dummy implementation of graph metrics to demonstrate how the interface
will look like

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## Description
<!-- Provide a clear description of the changes in this PR -->

## DCO Affirmation
I affirm that all code in every commit of this pull request conforms to
the terms of the Topoteretes Developer Certificate of Origin


<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit

- **New Features**
- Introduced asynchronous functionality for retrieving comprehensive
graph metrics, including counts and connectivity details, across
different systems.
  
- **Refactor**
- Streamlined metrics processing and storage by shifting to direct
retrieval from the graph engine.
- Updated naming conventions for the `GraphMetrics` database table and
reorganized module imports to enhance internal consistency.
  
- **Chores**
- Removed dataset deletion functionalities while introducing the ability
to store descriptive metrics.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: Igor Ilic <30923996+dexters1@users.noreply.github.com>

cognee/api/v1/cognify/cognify_v2.py

@@ -25,7 +25,7 @@ from cognee.tasks.documents import (
 )
 from cognee.tasks.graph import extract_graph_from_data
 from cognee.tasks.storage import add_data_points
-from cognee.tasks.storage.descriptive_metrics import store_descriptive_metrics
+from cognee.modules.data.methods import store_descriptive_metrics
 from cognee.tasks.storage.index_graph_edges import index_graph_edges
 from cognee.tasks.summarization import summarize_text
 

cognee/infrastructure/databases/graph/graph_db_interface.py

@@ -54,3 +54,7 @@ class GraphDBInterface(Protocol):
     @abstractmethod
     async def get_graph_data(self):
         raise NotImplementedError
+
+    @abstractmethod
+    async def get_graph_metrics(self):
+        raise NotImplementedError

cognee/infrastructure/databases/graph/neo4j_driver/adapter.py

@@ -530,3 +530,17 @@ class Neo4jAdapter(GraphDBInterface):
         ]
 
         return (nodes, edges)
+
+    async def get_graph_metrics(self):
+        return {
+            "num_nodes": -1,
+            "num_edges": -1,
+            "mean_degree": -1,
+            "edge_density": -1,
+            "num_connected_components": -1,
+            "sizes_of_connected_components": -1,
+            "num_selfloops": -1,
+            "diameter": -1,
+            "avg_shortest_path_length": -1,
+            "avg_clustering": -1,
+        }

cognee/infrastructure/databases/graph/networkx/adapter.py

@@ -385,3 +385,17 @@ class NetworkXAdapter(GraphDBInterface):
         ]
 
         return filtered_nodes, filtered_edges
+
+    async def get_graph_metrics(self):
+        return {
+            "num_nodes": -1,
+            "num_edges": -1,
+            "mean_degree": -1,
+            "edge_density": -1,
+            "num_connected_components": -1,
+            "sizes_of_connected_components": -1,
+            "num_selfloops": -1,
+            "diameter": -1,
+            "avg_shortest_path_length": -1,
+            "avg_clustering": -1,
+        }

cognee/modules/data/methods/__init__.py

@@ -11,3 +11,5 @@ from .get_data import get_data
 # Delete
 from .delete_dataset import delete_dataset
 from .delete_data import delete_data
+
+from .store_descriptive_metrics import store_descriptive_metrics

cognee/modules/data/methods/store_descriptive_metrics.py

@@ -1,5 +1,4 @@
 from cognee.infrastructure.engine import DataPoint
-from cognee.modules.data.processing.document_types import Document
 from cognee.infrastructure.databases.relational import get_relational_engine
 from sqlalchemy import select
 from sqlalchemy.sql import func
@@ -24,25 +23,28 @@ async def fetch_token_count(db_engine) -> int:
     return token_count_sum
 
 
-async def calculate_graph_metrics(graph_data):
-    nodes, edges = graph_data
-    graph_metrics = {
-        "num_nodes": len(nodes),
-        "num_edges": len(edges),
-    }
-    return graph_metrics
-
-
 async def store_descriptive_metrics(data_points: list[DataPoint]):
     db_engine = get_relational_engine()
     graph_engine = await get_graph_engine()
-    graph_data = await graph_engine.get_graph_data()
+    graph_metrics = await graph_engine.get_graph_metrics()
 
-    token_count_sum = await fetch_token_count(db_engine)
-    graph_metrics = await calculate_graph_metrics(graph_data)
+    async with db_engine.get_async_session() as session:
+        metrics = GraphMetrics(
+            id=uuid.uuid4(),
+            num_tokens=await fetch_token_count(db_engine),
+            num_nodes=graph_metrics["num_nodes"],
+            num_edges=graph_metrics["num_edges"],
+            mean_degree=graph_metrics["mean_degree"],
+            edge_density=graph_metrics["edge_density"],
+            num_connected_components=graph_metrics["num_connected_components"],
+            sizes_of_connected_components=graph_metrics["sizes_of_connected_components"],
+            num_selfloops=graph_metrics["num_selfloops"],
+            diameter=graph_metrics["diameter"],
+            avg_shortest_path_length=graph_metrics["avg_shortest_path_length"],
+            avg_clustering=graph_metrics["avg_clustering"],
+        )
 
-    table_name = "graph_metrics_table"
-    metrics_dict = {"id": uuid.uuid4(), "num_tokens": token_count_sum} | graph_metrics
+        session.add(metrics)
+        await session.commit()
 
-    await db_engine.insert_data(table_name, metrics_dict)
     return data_points

cognee/modules/data/models/GraphMetrics.py

@@ -7,7 +7,7 @@ from uuid import uuid4
 
 
 class GraphMetrics(Base):
-    __tablename__ = "graph_metrics_table"
+    __tablename__ = "graph_metrics"
 
     # TODO: Change ID to reflect unique id of graph database
     id = Column(UUID, primary_key=True, default=uuid4)

cognee/modules/data/models/__init__.py

@@ -1,3 +1,4 @@
 from .Data import Data
 from .Dataset import Dataset
 from .DatasetData import DatasetData
+from .GraphMetrics import GraphMetrics