fix node type filter

raphtory/src/db/api/view/node.rs

@@ -11,7 +11,7 @@
         storage::locked::LockedGraph,
         view::{
             internal::{CoreGraphOps, TimeSemantics},
-            TimeOps,
+            Base, TimeOps,
         },
     },
     prelude::{EdgeViewOps, GraphViewOps, LayerOps},
@@ -91,7 +91,7 @@
     /// Gets the history of the node (time that the node was added and times when changes were made to the node)
     fn history(&self) -> Self::ValueType<Vec<i64>>;
 
     /// Gets the history of the node (time that the node was added and times when changes were made to the node) as DateTime<Utc> objects if parseable
     fn history_date_time(&self) -> Self::ValueType<Option<Vec<DateTime<Utc>>>>;
 
     /// Get a view of the temporal properties of this node.

raphtory/src/db/graph/graph.rs

@@ -217,7 +217,9 @@ mod db_tests {
                     EdgeViewOps, Layer, LayerOps, NodeViewOps, TimeOps,
                 },
             },
-            graph::{edge::EdgeView, edges::Edges, node::NodeView, path::PathFromNode},
+            graph::{
+                edge::EdgeView, edges::Edges, node::NodeView, nodes::Nodes, path::PathFromNode,
+            },
         },
         graphgen::random_attachment::random_attachment,
         prelude::{AdditionOps, PropertyAdditionOps},
@@ -2154,6 +2156,26 @@ mod db_tests {
         );
     }
 
+    #[test]
+    fn test_node_type() {
+        let g = Graph::new();
+        g.add_node(1, 1, NO_PROPS, Some("a")).unwrap();
+        g.add_node(2, 2, NO_PROPS, Some("b")).unwrap();
+        g.add_node(2, 3, NO_PROPS, Some("b")).unwrap();
+        g.add_edge(3, 1, 2, NO_PROPS, None).unwrap();
+        g.add_edge(3, 3, 2, NO_PROPS, None).unwrap();
+
+        for node in g.nodes().filter_by_type(vec!["a"]) {
+            assert_eq!(node.degree(), 1);
+        }
+
+        for node in g.nodes() {
+            if node.node_type() == Some(ArcStr::from("a")) {
+                assert_eq!(node.degree(), 1);
+            }
+        }
+    }
+
     #[test]
     fn test_persistent_graph() {
         let g = Graph::new();

raphtory/src/db/graph/nodes.rs

@@ -14,10 +14,15 @@
     prelude::*,
 };
 
-use crate::db::api::storage::locked::LockedGraph;
+use crate::{core::ArcStr, db::api::storage::locked::LockedGraph};
 use itertools::Itertools;
 use rayon::iter::ParallelIterator;
-use std::{marker::PhantomData, sync::Arc};
+use std::{
+    borrow::Borrow,
+    iter::{FilterMap, FlatMap, Map},
+    marker::PhantomData,
+    sync::Arc,
+};
 
 #[derive(Clone)]
 pub struct Nodes<'graph, G, GH = G> {
@@ -96,6 +101,29 @@
         ))
     }
 
+    pub fn filter_by_type<I: IntoIterator<Item = V>, V: AsRef<str>>(
+        &self,
+        node_types: I,
+    ) -> BoxedLIter<'graph, NodeView<G, G>>
+    where
+        I::IntoIter: Send + Sync + 'graph,
+        V: Send + Sync + 'graph,
+    {
+        let base_graph = self.base_graph.clone();
+        node_types
+            .into_iter()
+            .flat_map(move |nt| {
+                base_graph.nodes().into_iter().filter_map(move |node| {
+                    if nt.as_ref() == node.node_type()?.as_ref() {
+                        Some(node)
+                    } else {
+                        None
+                    }
+                })
+            })
+            .into_dyn_boxed()
+    }
+
     pub fn collect(&self) -> Vec<NodeView<G, GH>> {
         self.iter().collect()
     }