Add new procs for virtual paths and graphs (#2153)

Fixes #914

Co-authored-by: Giuseppe Villani <[email protected]>

core/src/main/java/apoc/create/Create.java

@@ -220,6 +220,30 @@ public Stream<VirtualPathResult> virtualPath(@Name("labelsN") List<String> label
         return Stream.of(new VirtualPathResult(from, rel, to));
     }
 
+    @Procedure
+    @Description("apoc.create.clonePathToVirtual")
+    public Stream<PathResult> clonePathToVirtual(@Name("path") Path path) {
+        return Stream.of(createVirtualPath(path));
+    }
+
+    @Procedure
+    @Description("apoc.create.clonePathsToVirtual")
+    public Stream<PathResult> clonePathsToVirtual(@Name("paths") List<Path> paths) {
+        return paths.stream().map(this::createVirtualPath);
+    }
+
+    private PathResult createVirtualPath(Path path) {
+        final Iterable<Relationship> relationships = path.relationships();
+        final Node first = path.startNode();
+        VirtualPath virtualPath = new VirtualPath(new VirtualNode(first, Iterables.asList(first.getPropertyKeys())));
+        for (Relationship rel : relationships) {
+            VirtualNode start = VirtualNode.from(rel.getStartNode());
+            VirtualNode end = VirtualNode.from(rel.getEndNode());
+            virtualPath.addRel(VirtualRelationship.from(start, end, rel));
+        }
+        return new PathResult(virtualPath);
+    }
+
     private <T extends Entity> T setProperties(T pc, Map<String, Object> p) {
         if (p == null) return pc;
         for (Map.Entry<String, Object> entry : p.entrySet()) {

core/src/main/java/apoc/graph/Graphs.java

@@ -71,7 +71,7 @@ else if (data instanceof Iterator) {
         return found;
     }
 
-    @Description("apoc.graph.fromPaths(path,'name',{properties}) - creates a virtual graph object for later processing")
+    @Description("apoc.graph.fromPath(path,'name',{properties}) - creates a virtual graph object for later processing")
     @Procedure
     public Stream<VirtualGraph> fromPath(@Name("path") Path paths, @Name("name") String name, @Name("properties") Map<String,Object> properties) {
         return Stream.of(new VirtualGraph(name, paths.nodes(), paths.relationships(),properties));

core/src/main/java/apoc/result/VirtualNode.java

@@ -45,6 +45,10 @@ public VirtualNode(Node node, List<String> propertyNames) {
         this.props.putAll(node.getProperties(keys));
     }
 
+    public static VirtualNode from(Node node) {
+        return new VirtualNode(node, Iterables.asList(node.getPropertyKeys()));
+    }
+
     @Override
     public long getId() {
         return id;

core/src/main/java/apoc/result/VirtualPath.java

@@ -0,0 +1,121 @@
+package apoc.result;
+
+import org.neo4j.graphdb.Entity;
+import org.neo4j.graphdb.Node;
+import org.neo4j.graphdb.Path;
+import org.neo4j.graphdb.Relationship;
+import org.neo4j.graphdb.traversal.Paths;
+
+import javax.annotation.Nonnull;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Objects;
+import java.util.concurrent.atomic.AtomicReference;
+import java.util.stream.Collectors;
+
+import static org.apache.commons.collections4.IterableUtils.reversedIterable;
+
+
+public class VirtualPath implements Path {
+
+    private final Node start;
+    private final List<Relationship> relationships = new ArrayList<>();
+
+    public VirtualPath(Node start) {
+        Objects.requireNonNull(start);
+        this.start = start;
+    }
+
+    public void addRel(Relationship relationship) {
+        Objects.requireNonNull(relationship);
+        this.relationships.add(relationship);
+    }
+
+    @Override
+    public Node startNode() {
+        return start;
+    }
+
+    @Override
+    public Node endNode() {
+        return reverseNodes().iterator().next();
+    }
+
+    @Override
+    public Relationship lastRelationship() {
+        return relationships.isEmpty() ? null : relationships.get(relationships.size() - 1);
+    }
+
+    @Override
+    public Iterable<Relationship> relationships() {
+        return relationships;
+    }
+
+    @Override
+    public Iterable<Relationship> reverseRelationships() {
+        return reversedIterable(relationships());
+    }
+
+    @Override
+    public Iterable<Node> nodes() {
+        List<Node> nodes = new ArrayList<>();
+        nodes.add(start);
+
+        AtomicReference<Node> currNode = new AtomicReference<>(start);
+        final List<Node> otherNodes = relationships.stream().map(rel -> {
+            final Node otherNode = rel.getOtherNode(currNode.get());
+            currNode.set(otherNode);
+            return otherNode;
+        }).collect(Collectors.toList());
+
+        nodes.addAll(otherNodes);
+        return nodes;
+    }
+
+    @Override
+    public Iterable<Node> reverseNodes() {
+        return reversedIterable(nodes());
+    }
+
+    @Override
+    public int length() {
+        return relationships.size();
+    }
+
+    @Override
+    @Nonnull
+    public Iterator<Entity> iterator() {
+        return new Iterator<>() {
+            Iterator<? extends Entity> current = nodes().iterator();
+            Iterator<? extends Entity> next = relationships().iterator();
+
+            @Override
+            public boolean hasNext() {
+                return current.hasNext();
+            }
+
+            @Override
+            public Entity next() {
+                try {
+                    return current.next();
+                }
+                finally {
+                    Iterator<? extends Entity> temp = current;
+                    current = next;
+                    next = temp;
+                }
+            }
+
+            @Override
+            public void remove() {
+                next.remove();
+            }
+        };
+    }
+
+    @Override
+    public String toString() {
+        return Paths.defaultPathToString(this);
+    }
+}

core/src/main/java/apoc/result/VirtualRelationship.java

@@ -37,6 +37,10 @@ public VirtualRelationship(long id, Node startNode, Node endNode, RelationshipTy
         this.type = type;
         this.props.putAll(props);
     }
+
+    public static Relationship from(VirtualNode start, VirtualNode end, Relationship rel) {
+        return new VirtualRelationship(start, end, rel.getType()).withProperties(rel.getAllProperties());
+    }
 
     @Override
     public long getId() {

core/src/test/java/apoc/create/CreateTest.java

@@ -6,16 +6,23 @@
 import org.junit.Test;
 import org.neo4j.graphdb.Label;
 import org.neo4j.graphdb.Node;
+import org.neo4j.graphdb.Path;
 import org.neo4j.graphdb.Relationship;
 import org.neo4j.graphdb.RelationshipType;
+import org.neo4j.graphdb.ResourceIterator;
+import org.neo4j.internal.helpers.collection.Iterables;
 import org.neo4j.test.rule.DbmsRule;
 import org.neo4j.test.rule.ImpermanentDbmsRule;
 
+import java.util.Iterator;
+import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 import static apoc.util.TestUtil.testCall;
 import static apoc.util.TestUtil.testResult;
 import static org.junit.Assert.*;
+import static org.neo4j.graphdb.Label.label;
 
 public class CreateTest {
 
@@ -228,5 +235,66 @@ public void testVirtualFromNodeFunction() throws Exception {
                     assertNull(node.getProperty("born"));
                 });
     }
+
+    @Test
+    public void testVirtualPath() {
+        db.executeTransactionally("CREATE p=(a:Test {foo: 7})-[:TEST]->(b:Baa:Baz {a:'b'})<-[:TEST_2 {aa:'bb'}]-(:Bar {one:'www'}), \n" +
+                "q=(:Omega {alpha: 'beta'})<-[:TEST_3 {aa:'ccc'}]-(:Bar {one:'jjj'})");
+        testCall(db, "MATCH p=(a:Test {foo: 7})-[:TEST]->(b:Baa:Baz {a:'b'})<-[:TEST_2 {aa:'bb'}]-(:Bar {one:'www'}) WITH p \n" +
+                        "CALL apoc.create.clonePathToVirtual(p) YIELD path RETURN path",
+                (row) -> assertionsFirstVirtualPath((Path) row.get("path")));
+
+        testResult(db, "MATCH p=(a:Test {foo: 7})-[:TEST]->(b:Baa:Baz {a:'b'})<-[:TEST_2 {aa:'bb'}]-(:Bar {one:'www'}), \n" +
+                        "q=(:Omega {alpha: 'beta'})<-[:TEST_3 {aa:'ccc'}]-(:Bar {one:'jjj'}) WITH [p, q] as paths \n" +
+                        "CALL apoc.create.clonePathsToVirtual(paths) YIELD path RETURN path",
+                (res) -> {
+                    ResourceIterator<Path> paths = res.columnAs("path");
+                    Path firstPath = paths.next();
+                    assertionsFirstVirtualPath(firstPath);
+                    Path secondPath = paths.next();
+                    Iterator<Node> nodes = secondPath.nodes().iterator();
+                    Node firstNode = nodes.next();
+                    assertEquals(List.of(label("Omega")), firstNode.getLabels());
+                    assertEquals(Map.of("alpha", "beta"), firstNode.getAllProperties());
+
+                    Node secondNode = nodes.next();
+                    assertEquals(List.of(label("Bar")), secondNode.getLabels());
+                    assertEquals(Map.of("one", "jjj"), secondNode.getAllProperties());
+                    assertFalse(nodes.hasNext());
+
+                    Iterator<Relationship> rels = secondPath.relationships().iterator();
+                    Relationship relationship = rels.next();
+                    assertEquals("TEST_3", relationship.getType().name());
+                    assertEquals(Map.of("aa", "ccc"), relationship.getAllProperties());
+                    assertFalse(rels.hasNext());
+                    assertFalse(paths.hasNext());
+                });
+    }
+
+    private void assertionsFirstVirtualPath(Path path) {
+        Iterator<Node> nodes = path.nodes().iterator();
+        Node firstNode = nodes.next();
+        assertEquals(List.of(label("Test")), firstNode.getLabels());
+        assertEquals(Map.of("foo", 7L), firstNode.getAllProperties());
+
+        Node secondNode = nodes.next();
+        assertEquals(Set.of(label("Baa"), label("Baz")), Iterables.asSet(secondNode.getLabels()));
+        assertEquals(Map.of("a", "b"), secondNode.getAllProperties());
+
+        Node thirdNode = nodes.next();
+        assertEquals(List.of(label("Bar")), thirdNode.getLabels());
+        assertEquals(Map.of("one", "www"), thirdNode.getAllProperties());
+        assertFalse(nodes.hasNext());
+
+        Iterator<Relationship> rels = path.relationships().iterator();
+        Relationship firstRel = rels.next();
+        assertEquals("TEST", firstRel.getType().name());
+        assertTrue(firstRel.getAllProperties().isEmpty());
+
+        Relationship secondRel = rels.next();
+        assertEquals("TEST_2", secondRel.getType().name());
+        assertEquals(Map.of("aa", "bb"), secondRel.getAllProperties());
+        assertFalse(rels.hasNext());
+    }
 
 }

docs/asciidoc/modules/ROOT/examples/generated-documentation/apoc.create-lite.csv

@@ -14,6 +14,8 @@
 ¦apoc.create.uuids(count :: INTEGER?) :: (row :: INTEGER?, uuid :: STRING?)
 ¦apoc.create.vNode(label :: LIST? OF STRING?, props :: MAP?) :: (node :: NODE?)
 ¦apoc.create.vNodes(label :: LIST? OF STRING?, props :: LIST? OF MAP?) :: (node :: NODE?)
+¦apoc.create.clonePathToVirtual(path :: PATH?) :: (path :: PATH?)
+¦apoc.create.clonePathsToVirtual(paths :: LIST? OF PATH?) :: (path :: PATH?)
 ¦apoc.create.vPattern(from :: MAP?, relType :: STRING?, props :: MAP?, to :: MAP?) :: (from :: NODE?, rel :: RELATIONSHIP?, to :: NODE?)
 ¦apoc.create.vPatternFull(labelsN :: LIST? OF STRING?, n :: MAP?, relType :: STRING?, props :: MAP?, labelsM :: LIST? OF STRING?, m :: MAP?) :: (from :: NODE?, rel :: RELATIONSHIP?, to :: NODE?)
 ¦apoc.create.vRelationship(from :: NODE?, relType :: STRING?, props :: MAP?, to :: NODE?) :: (rel :: RELATIONSHIP?)

docs/asciidoc/modules/ROOT/examples/generated-documentation/apoc.create.clonePathToVirtual-lite.csv

@@ -0,0 +1,2 @@
+¦signature
+¦apoc.create.clonePathToVirtual(path :: PATH?) :: (path :: PATH?)

docs/asciidoc/modules/ROOT/examples/generated-documentation/apoc.create.clonePathToVirtual.adoc

@@ -0,0 +1,5 @@
+¦xref::overview/apoc.create/apoc.create.clonePathToVirtual.adoc[apoc.create.clonePathToVirtual icon:book[]] +
+
+
+¦label:procedure[]
+¦label:apoc-core[]

docs/asciidoc/modules/ROOT/examples/generated-documentation/apoc.create.clonePathsToVirtual-lite.csv

@@ -0,0 +1,2 @@
+¦signature
+¦apoc.create.clonePathsToVirtual(paths :: LIST? OF PATH?) :: (path :: PATH?)

docs/asciidoc/modules/ROOT/examples/generated-documentation/apoc.create.clonePathsToVirtual.adoc

@@ -0,0 +1,5 @@
+¦xref::overview/apoc.create/apoc.create.clonePathsToVirtual.adoc[apoc.create.clonePathsToVirtual icon:book[]] +
+
+
+¦label:procedure[]
+¦label:apoc-core[]

docs/asciidoc/modules/ROOT/examples/generated-documentation/apoc.create.csv

@@ -74,6 +74,16 @@ apoc.create.vNode(['Label'], {key:value,...}) returns a virtual node
 apoc.create.vNodes(['Label'], [{key:value,...}]) returns virtual nodes
 |label:procedure[]
 |label:apoc-core[]
+|xref::overview/apoc.create/apoc.create.adoc[apoc.create.clonePathToVirtual icon:book[]]
+
+apoc.create.clonePathToVirtual
+|label:procedure[]
+|label:apoc-core[]
+|xref::overview/apoc.create/apoc.create.adoc[apoc.create.clonePathsToVirtual icon:book[]]
+
+apoc.create.clonePathsToVirtual
+|label:procedure[]
+|label:apoc-core[]
 |xref::overview/apoc.create/apoc.create.adoc[apoc.create.vPattern icon:book[]]
 
 apoc.create.vPattern({_labels:['LabelA'],key:value},'KNOWS',{key:value,...}, {_labels:['LabelB'],key:value}) returns a virtual pattern

docs/asciidoc/modules/ROOT/examples/generated-documentation/documentation.csv

@@ -50,6 +50,8 @@
 ¦procedure¦apoc.create.uuids¦apoc.create.uuids(count :: INTEGER?) :: (row :: INTEGER?, uuid :: STRING?)¦apoc.create.uuids(count) yield uuid - creates 'count' UUIDs ¦true¦
 ¦procedure¦apoc.create.vNode¦apoc.create.vNode(label :: LIST? OF STRING?, props :: MAP?) :: (node :: NODE?)¦apoc.create.vNode(['Label'], {key:value,...}) returns a virtual node¦true¦xref::virtual/virtual-nodes-rels.adoc
 ¦procedure¦apoc.create.vNodes¦apoc.create.vNodes(label :: LIST? OF STRING?, props :: LIST? OF MAP?) :: (node :: NODE?)¦apoc.create.vNodes(['Label'], [{key:value,...}]) returns virtual nodes¦true¦xref::virtual/virtual-nodes-rels.adoc
+¦procedure¦apoc.create.clonePathToVirtual¦apoc.create.clonePathToVirtual(path :: PATH?) :: (path :: PATH?)¦apoc.create.clonePathToVirtual¦true¦xref::virtual/virtual-nodes-rels.adoc
+¦procedure¦apoc.create.clonePathsToVirtual¦apoc.create.clonePathsToVirtual(paths :: LIST? OF PATH?) :: (path :: PATH?)¦apoc.create.clonePathsToVirtual¦true¦xref::virtual/virtual-nodes-rels.adoc
 ¦procedure¦apoc.create.vPattern¦apoc.create.vPattern(from :: MAP?, relType :: STRING?, props :: MAP?, to :: MAP?) :: (from :: NODE?, rel :: RELATIONSHIP?, to :: NODE?)¦apoc.create.vPattern({_labels:['LabelA'],key:value},'KNOWS',{key:value,...}, {_labels:['LabelB'],key:value}) returns a virtual pattern¦true¦xref::virtual/virtual-nodes-rels.adoc
 ¦procedure¦apoc.create.vPatternFull¦apoc.create.vPatternFull(labelsN :: LIST? OF STRING?, n :: MAP?, relType :: STRING?, props :: MAP?, labelsM :: LIST? OF STRING?, m :: MAP?) :: (from :: NODE?, rel :: RELATIONSHIP?, to :: NODE?)¦apoc.create.vPatternFull(['LabelA'],{key:value},'KNOWS',{key:value,...},['LabelB'],{key:value}) returns a virtual pattern¦true¦xref::virtual/virtual-nodes-rels.adoc
 ¦procedure¦apoc.create.vRelationship¦apoc.create.vRelationship(from :: NODE?, relType :: STRING?, props :: MAP?, to :: NODE?) :: (rel :: RELATIONSHIP?)¦apoc.create.vRelationship(nodeFrom,'KNOWS',{key:value,...}, nodeTo) returns a virtual relationship¦true¦xref::virtual/virtual-nodes-rels.adoc
@@ -123,7 +125,7 @@
 ¦procedure¦apoc.graph.fromDB¦apoc.graph.fromDB(name :: STRING?, properties :: MAP?) :: (graph :: MAP?)¦apoc.graph.fromDB('name',\{properties}) - creates a virtual graph object for later processing¦true¦xref::virtual/virtual-graph.adoc
 ¦procedure¦apoc.graph.fromData¦apoc.graph.fromData(nodes :: LIST? OF NODE?, relationships :: LIST? OF RELATIONSHIP?, name :: STRING?, properties :: MAP?) :: (graph :: MAP?)¦apoc.graph.fromData([nodes],[relationships],'name',\{properties}) | creates a virtual graph object for later processing¦true¦xref::virtual/virtual-graph.adoc
 ¦procedure¦apoc.graph.fromDocument¦apoc.graph.fromDocument(json :: ANY?, config = {} :: MAP?) :: (graph :: MAP?)¦apoc.graph.fromDocument(\{json}, \{config}) yield graph - transform JSON documents into graph structures¦true¦xref::virtual/virtual-graph.adoc
-¦procedure¦apoc.graph.fromPath¦apoc.graph.fromPath(path :: PATH?, name :: STRING?, properties :: MAP?) :: (graph :: MAP?)¦apoc.graph.fromPaths(path,'name',\{properties}) - creates a virtual graph object for later processing¦true¦xref::virtual/virtual-graph.adoc
+¦procedure¦apoc.graph.fromPath¦apoc.graph.fromPath(path :: PATH?, name :: STRING?, properties :: MAP?) :: (graph :: MAP?)¦apoc.graph.fromPath(path,'name',\{properties}) - creates a virtual graph object for later processing¦true¦xref::virtual/virtual-graph.adoc
 ¦procedure¦apoc.graph.fromPaths¦apoc.graph.fromPaths(paths :: LIST? OF PATH?, name :: STRING?, properties :: MAP?) :: (graph :: MAP?)¦apoc.graph.fromPaths([paths],'name',\{properties}) - creates a virtual graph object for later processing¦true¦xref::virtual/virtual-graph.adoc
 ¦procedure¦apoc.graph.validateDocument¦apoc.graph.validateDocument(json :: ANY?, config = {} :: MAP?) :: (row :: MAP?)¦apoc.graph.validateDocument(\{json}, \{config}) yield row - validates the json, return the result of the validation¦true¦xref::virtual/virtual-graph.adoc
 ¦procedure¦apoc.help¦apoc.help(proc :: STRING?) :: (type :: STRING?, name :: STRING?, text :: STRING?, signature :: STRING?, roles :: LIST? OF STRING?, writes :: BOOLEAN?, core :: BOOLEAN?)¦Provides descriptions of available procedures. To narrow the results, supply a search string. To also search in the description text, append + to the end of the search string.¦true¦

docs/asciidoc/modules/ROOT/pages/overview/apoc.create/apoc.create.clonePathToVirtual.adoc

@@ -0,0 +1,35 @@
+////
+This file is generated by DocsTest, so don't change it!
+////
+
+= apoc.create.clonePathToVirtual
+:description: This section contains reference documentation for the apoc.create.clonePathToVirtual procedure.
+
+label:procedure[] label:apoc-core[]
+
+[.emphasis]
+apoc.create.clonePathToVirtual
+
+== Signature
+
+[source]
+----
+apoc.create.clonePathToVirtual(path :: PATH?) :: (path :: PATH?)
+----
+
+== Input parameters
+[.procedures, opts=header]
+|===
+| Name | Type | Default 
+|path|PATH?|null
+|===
+
+== Output parameters
+[.procedures, opts=header]
+|===
+| Name | Type 
+|path|PATH?
+|===
+
+xref::virtual/virtual-nodes-rels.adoc[More documentation of apoc.create.clonePathToVirtual,role=more information]
+