lib/redgraph/graph.rb in redgraph-0.1.1 vs lib/redgraph/graph.rb in redgraph-0.1.2

@@ -47,10 +47,17 @@
     def properties
       result = query("CALL db.propertyKeys()")
       result.resultset.map(&:values).flatten
     end
 
+    # Returns an array of existing relationship types
+    #
+    def relationship_types
+      result = query("CALL db.relationshipTypes()")
+      result.resultset.map(&:values).flatten
+    end
+
     # Adds a node. If successul it returns the created object, otherwise false
     #
     def add_node(node)
       result = query("CREATE (n:`#{node.label}` #{quote_hash(node.properties)}) RETURN ID(n)")
       return false if result.stats[:nodes_created] != 1
@@ -88,22 +95,29 @@
 
       cmd = "MATCH (node#{_label} #{_props}) RETURN node #{_skip} #{_limit}"
       result = query(cmd)
 
       result.resultset.map do |item|
-        (node_id, labels, props) = item["node"]
-        attrs = {}
-
-        props.each do |(index, type, value)|
-          attrs[get_property(index)] = value
-        end
-        Node.new(label: get_label(labels.first), properties: attrs).tap do |node|
-          node.id = node_id
-        end
+        node_from_resultset_item(item["node"])
       end
     end
 
+    # Counts nodes. Options:
+    #
+    # - label: filter by label
+    # - properties: filter by properties
+    #
+    def count_nodes(label: nil, properties: nil)
+      _label = ":`#{label}`" if label
+      _props = quote_hash(properties) if properties
+
+      cmd = "MATCH (node#{_label} #{_props}) RETURN COUNT(node)"
+      result = query(cmd)
+
+      result.resultset.first["COUNT(node)"]
+    end
+
     # Adds an edge. If successul it returns the created object, otherwise false
     #
     def add_edge(edge)
       result = query("MATCH (src), (dest)
                       WHERE ID(src) = #{edge.src.id} AND ID(dest) = #{edge.dest.id}
@@ -112,10 +126,49 @@
       id = result.resultset.first["ID(e)"]
       edge.id = id
       edge
     end
 
+    # Finds edges. Options:
+    #
+    # - type
+    # - src
+    # - dest
+    # - properties
+    # - limit
+    # - skip
+    #
+    def edges(type: nil, src: nil, dest: nil, properties: nil, limit: nil, skip: nil)
+      _type = ":`#{type}`" if type
+      _props = quote_hash(properties) if properties
+      _limit = "LIMIT #{limit}" if limit
+      _skip = "SKIP #{skip}" if skip
+
+      _where = if src || dest
+        clauses = [
+          ("ID(src) = #{src.id}" if src),
+          ("ID(dest) = #{dest.id}" if dest)
+        ].compact.join(" AND ")
+        "WHERE #{clauses}"
+      end
+
+      cmd = "MATCH (src)-[edge#{_type} #{_props}]->(dest) #{_where}
+             RETURN src, edge, dest #{_skip} #{_limit}"
+      result = query(cmd)
+
+      result.resultset.map do |item|
+        src = node_from_resultset_item(item["src"])
+        dest = node_from_resultset_item(item["dest"])
+        edge = edge_from_resultset_item(item["edge"])
+
+        edge.src = src
+        edge.dest = dest
+
+        edge
+      end
+    end
+
     private
 
     def query(cmd)
       data = @connection.call("GRAPH.QUERY", graph_name, cmd, "--compact")
       QueryResponse.new(data)
@@ -128,12 +181,13 @@
     end
 
     def escape_value(x)
       case x
       when Integer then x
+      when NilClass then "''"
       else
-        "'#{x}'"
+        '"' + x.gsub('"', '\"') + '"'
       end
     end
 
     def get_label(id)
       @labels ||= labels
@@ -141,8 +195,42 @@
     end
 
     def get_property(id)
       @properties ||= properties
       @properties[id] || (@properties = properties)[id]
+    end
+
+    def get_relationship_type(id)
+      @relationship_types ||= relationship_types
+      @relationship_types[id] || (@relationship_types = relationship_types)[id]
+    end
+
+    # Builds a Node object from the raw data
+    #
+    def node_from_resultset_item(item)
+      (node_id, labels, props) = item
+      attrs = {}
+
+      props.each do |(index, type, value)|
+        attrs[get_property(index)] = value
+      end
+      Node.new(label: get_label(labels.first), properties: attrs).tap do |node|
+        node.id = node_id
+      end
+    end
+
+    def edge_from_resultset_item(item)
+      (edge_id, type_id, _src_id, _dest_id, props) = item
+      attrs = {}
+
+      props.each do |(index, type, value)|
+        attrs[get_property(index)] = value
+      end
+
+      Edge.new.tap do |edge|
+        edge.id = edge_id
+        edge.type = get_relationship_type(type_id)
+        edge.properties = attrs
+      end
     end
   end
 end