src/backend/utils/graph_generation.c - age - Git at Google

 /*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
  * regarding copyright ownership.  The ASF licenses this file
  * to you under the Apache License, Version 2.0 (the
  * "License"); you may not use this file except in compliance
  * with the License.  You may obtain a copy of the License at
  *
  * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing,
  * software distributed under the License is distributed on an
  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  * KIND, either express or implied.  See the License for the
  * specific language governing permissions and limitations
  * under the License.
  */

 #include "postgres.h"

 #include "access/genam.h"
 #include "commands/graph_commands.h"
 #include "utils/load/age_load.h"


 int64 get_nextval_internal(graph_cache_data* graph_cache,
                            label_cache_data* label_cache);
 /*
  * Auxiliary function to get the next internal value in the graph,
  * so a new object (node or edge) graph id can be composed.
  */

 int64 get_nextval_internal(graph_cache_data* graph_cache,
                            label_cache_data* label_cache)
 {
     Oid obj_seq_id;
     char* label_seq_name_str;

     label_seq_name_str = NameStr(label_cache->seq_name);
     obj_seq_id = get_relname_relid(label_seq_name_str,
                                    graph_cache->namespace);

     return nextval_internal(obj_seq_id, true);
 }

 PG_FUNCTION_INFO_V1(create_complete_graph);

 /*
 * SELECT * FROM ag_catalog.create_complete_graph('graph_name',no_of_nodes, 'edge_label', 'node_label'=NULL);
 */

 Datum create_complete_graph(PG_FUNCTION_ARGS)
 {
     Oid graph_oid;
     Name graph_name;

     int64 no_vertices;
     int64 i,j,vid = 1, eid, start_vid, end_vid;

     Name vtx_label_name = NULL;
     Name edge_label_name;
     int32 vtx_label_id;
     int32 edge_label_id;

     agtype *props = NULL;
     graphid object_graph_id;
     graphid start_vertex_graph_id;
     graphid end_vertex_graph_id;

     Oid vtx_seq_id;
     Oid edge_seq_id;

     char* graph_name_str;
     char* vtx_name_str;
     char* edge_name_str;

     graph_cache_data *graph_cache;
     label_cache_data *vertex_cache;
     label_cache_data *edge_cache;

     Oid nsp_id;
     Name vtx_seq_name;
     char *vtx_seq_name_str;

     Name edge_seq_name;
     char *edge_seq_name_str;

     int64 lid;

     if (PG_ARGISNULL(0))
     {
         ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("graph name can not be NULL")));
     }

     if (PG_ARGISNULL(1))
     {
         ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("number of nodes can not be NULL")));
     }

     if (PG_ARGISNULL(2))
     {
         ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("edge label can not be NULL")));
     }

     graph_name = PG_GETARG_NAME(0);
     no_vertices = (int64) PG_GETARG_INT64(1);
     edge_label_name = PG_GETARG_NAME(2);

     graph_name_str = NameStr(*graph_name);
     vtx_name_str = AG_DEFAULT_LABEL_VERTEX;
     edge_name_str = NameStr(*edge_label_name);

     if (!PG_ARGISNULL(3))
     {
         vtx_label_name = PG_GETARG_NAME(3);
         vtx_name_str = NameStr(*vtx_label_name);

         /* Check if vertex and edge label are same */
         if (strcmp(vtx_name_str, edge_name_str) == 0)
         {
             ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                     errmsg("vertex and edge label can not be same")));
         }
     }

     if (!graph_exists(graph_name_str))
     {
         DirectFunctionCall1(create_graph, CStringGetDatum(graph_name->data));
     }

     graph_oid = get_graph_oid(graph_name_str);

     if (!PG_ARGISNULL(3))
     {
         /* Check if label with the input name already exists */
         if (!label_exists(vtx_name_str, graph_oid))
         {
             DirectFunctionCall2(create_vlabel,
                                 CStringGetDatum(graph_name->data),
                                 CStringGetDatum(vtx_label_name->data));
         }
     }

     if (!label_exists(edge_name_str, graph_oid))
     {
         DirectFunctionCall2(create_elabel,
                             CStringGetDatum(graph_name->data),
                             CStringGetDatum(edge_label_name->data));
     }

     vtx_label_id = get_label_id(vtx_name_str, graph_oid);
     edge_label_id = get_label_id(edge_name_str, graph_oid);

     graph_cache = search_graph_name_cache(graph_name_str);
     vertex_cache = search_label_name_graph_cache(vtx_name_str, graph_oid);
     edge_cache = search_label_name_graph_cache(edge_name_str, graph_oid);

     nsp_id = graph_cache->namespace;
     vtx_seq_name = &(vertex_cache->seq_name);
     vtx_seq_name_str = NameStr(*vtx_seq_name);

     edge_seq_name = &(edge_cache->seq_name);
     edge_seq_name_str = NameStr(*edge_seq_name);

     vtx_seq_id = get_relname_relid(vtx_seq_name_str, nsp_id);
     edge_seq_id = get_relname_relid(edge_seq_name_str, nsp_id);

     props = create_empty_agtype();

     /* Creating vertices*/
     for (i=(int64)1; i<=no_vertices; i++)
     {
         vid = nextval_internal(vtx_seq_id, true);
         object_graph_id = make_graphid(vtx_label_id, vid);
         insert_vertex_simple(graph_oid, vtx_name_str, object_graph_id, props);
     }

     lid = vid;

     /* Creating edges*/
     for (i = 1; i<=no_vertices-1; i++)
     {
         start_vid = lid-no_vertices+i;
         for(j=i+1; j<=no_vertices; j++)
         {
             end_vid = lid-no_vertices+j;
             eid = nextval_internal(edge_seq_id, true);
             object_graph_id = make_graphid(edge_label_id, eid);

             start_vertex_graph_id = make_graphid(vtx_label_id, start_vid);
             end_vertex_graph_id = make_graphid(vtx_label_id, end_vid);

             insert_edge_simple(graph_oid, edge_name_str, object_graph_id,
                                start_vertex_graph_id, end_vertex_graph_id,
                                props);
         }
     }
     PG_RETURN_VOID();
 }


 PG_FUNCTION_INFO_V1(age_create_barbell_graph);

 /*
  * The barbell graph is two complete graphs connected by a bridge path
  * Syntax:
  * ag_catalog.age_create_barbell_graph(graph_name Name,
  *                                     m int,
  *                                     n int,
  *                                     vertex_label_name Name DEFAULT = NULL,
  *                                     vertex_properties agtype DEFAULT = NULL,
  *                                     edge_label_name Name DEFAULT = NULL,
  *                                     edge_properties agtype DEFAULT = NULL)
  * Input:
  *
  * graph_name - Name of the graph to be created.
  * m - number of vertices in one complete graph.
  * n - number of vertices in the bridge path.
  * vertex_label_name - Name of the label to assign each vertex to.
  * vertex_properties - Property values to assign each vertex. Default is NULL
  * edge_label_name - Name of the label to assign each edge to.
  * edge_properties - Property values to assign each edge. Default is NULL
  *
  * https://en.wikipedia.org/wiki/Barbell_graph
  */

 Datum age_create_barbell_graph(PG_FUNCTION_ARGS)
 {
     FunctionCallInfo arguments;
     Oid graph_oid;
     Name graph_name;
     char* graph_name_str;

     int64 start_node_index, end_node_index, nextval;

     Name node_label_name = NULL;
     int32 node_label_id;
     char* node_label_str;

     Name edge_label_name;
     int32 edge_label_id;
     char* edge_label_str;

     graphid object_graph_id;
     graphid start_node_graph_id;
     graphid end_node_graph_id;

     graph_cache_data* graph_cache;
     label_cache_data* edge_cache;

     agtype* properties = NULL;

     arguments = fcinfo;

     /* Checking for possible NULL arguments */
     /* Name graph_name */
     if (PG_ARGISNULL(0))
     {
         ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                         errmsg("Graph name cannot be NULL")));
     }

     graph_name = PG_GETARG_NAME(0);
     graph_name_str = NameStr(*graph_name);

     /* int graph size (number of nodes in each complete graph) */
     if (PG_ARGISNULL(1) && PG_GETARG_INT32(1) < 3)
     {
         ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                 errmsg("Graph size cannot be NULL or lower than 3")));
     }

     /*
      * int64 bridge_size: currently only stays at zero.
      * to do: implement bridge with variable number of nodes.
      */
     if (PG_ARGISNULL(2) || PG_GETARG_INT32(2) < 0 )
     {
         ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                 errmsg("Bridge size cannot be NULL or lower than 0")));
     }

     /* node label: if null, gets default label, which is "_ag_label_vertex" */
     if (PG_ARGISNULL(3))
     {
         namestrcpy(node_label_name, AG_DEFAULT_LABEL_VERTEX);
     }
     else
     {
         node_label_name = PG_GETARG_NAME(3);
     }
     node_label_str = NameStr(*node_label_name);

     /* Name edge_label */
     if (PG_ARGISNULL(5))
     {
         ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
                 errmsg("edge label can not be NULL")));
     }

     edge_label_name = PG_GETARG_NAME(5);
     edge_label_str = NameStr(*edge_label_name);


     /* create two separate complete graphs */
     DirectFunctionCall4(create_complete_graph, arguments->args[0].value,
                                                arguments->args[1].value,
                                                arguments->args[5].value,
                                                arguments->args[3].value);
     DirectFunctionCall4(create_complete_graph, arguments->args[0].value,
                                                arguments->args[1].value,
                                                arguments->args[5].value,
                                                arguments->args[3].value);

     graph_oid = get_graph_oid(graph_name_str);
     node_label_id = get_label_id(node_label_str, graph_oid);
     edge_label_id = get_label_id(edge_label_str, graph_oid);

     /*
      * Fetching caches to get next values for graph id's, and access nodes
      * to be connected with edges.
      */
     graph_cache = search_graph_name_cache(graph_name_str);
     edge_cache = search_label_name_graph_cache(edge_label_str,graph_oid);

     /* connect a node from each graph */
     /* first created node, from the first complete graph */
     start_node_index = 1;
     /* last created node, second graph */
     end_node_index = arguments->args[1].value*2;

     /* next index to be assigned to a node or edge */
     nextval = get_nextval_internal(graph_cache, edge_cache);

     /* build the graph id's of the edge to be created */
     object_graph_id = make_graphid(edge_label_id, nextval);
     start_node_graph_id = make_graphid(node_label_id, start_node_index);
     end_node_graph_id = make_graphid(node_label_id, end_node_index);
     properties = create_empty_agtype();

     /* connect two nodes */
     insert_edge_simple(graph_oid, edge_label_str,
                        object_graph_id, start_node_graph_id,
                        end_node_graph_id, properties);

     PG_RETURN_VOID();
 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one
	* or more contributor license agreements. See the NOTICE file
	* distributed with this work for additional information
	* regarding copyright ownership. The ASF licenses this file
	* to you under the Apache License, Version 2.0 (the
	* "License"); you may not use this file except in compliance
	* with the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing,
	* software distributed under the License is distributed on an
	* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
	* KIND, either express or implied. See the License for the
	* specific language governing permissions and limitations
	* under the License.
	*/

	#include "postgres.h"

	#include "access/genam.h"
	#include "commands/graph_commands.h"
	#include "utils/load/age_load.h"


	int64 get_nextval_internal(graph_cache_data* graph_cache,
	label_cache_data* label_cache);
	/*
	* Auxiliary function to get the next internal value in the graph,
	* so a new object (node or edge) graph id can be composed.
	*/

	int64 get_nextval_internal(graph_cache_data* graph_cache,
	label_cache_data* label_cache)
	{
	Oid obj_seq_id;
	char* label_seq_name_str;

	label_seq_name_str = NameStr(label_cache->seq_name);
	obj_seq_id = get_relname_relid(label_seq_name_str,
	graph_cache->namespace);

	return nextval_internal(obj_seq_id, true);
	}

	PG_FUNCTION_INFO_V1(create_complete_graph);

	/*
	* SELECT * FROM ag_catalog.create_complete_graph('graph_name',no_of_nodes, 'edge_label', 'node_label'=NULL);
	*/

	Datum create_complete_graph(PG_FUNCTION_ARGS)
	{
	Oid graph_oid;
	Name graph_name;

	int64 no_vertices;
	int64 i,j,vid = 1, eid, start_vid, end_vid;

	Name vtx_label_name = NULL;
	Name edge_label_name;
	int32 vtx_label_id;
	int32 edge_label_id;

	agtype *props = NULL;
	graphid object_graph_id;
	graphid start_vertex_graph_id;
	graphid end_vertex_graph_id;

	Oid vtx_seq_id;
	Oid edge_seq_id;

	char* graph_name_str;
	char* vtx_name_str;
	char* edge_name_str;

	graph_cache_data *graph_cache;
	label_cache_data *vertex_cache;
	label_cache_data *edge_cache;

	Oid nsp_id;
	Name vtx_seq_name;
	char *vtx_seq_name_str;

	Name edge_seq_name;
	char *edge_seq_name_str;

	int64 lid;

	if (PG_ARGISNULL(0))
	{
	ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
	errmsg("graph name can not be NULL")));
	}

	if (PG_ARGISNULL(1))
	{
	ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
	errmsg("number of nodes can not be NULL")));
	}

	if (PG_ARGISNULL(2))
	{
	ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
	errmsg("edge label can not be NULL")));
	}

	graph_name = PG_GETARG_NAME(0);
	no_vertices = (int64) PG_GETARG_INT64(1);
	edge_label_name = PG_GETARG_NAME(2);

	graph_name_str = NameStr(*graph_name);
	vtx_name_str = AG_DEFAULT_LABEL_VERTEX;
	edge_name_str = NameStr(*edge_label_name);

	if (!PG_ARGISNULL(3))
	{
	vtx_label_name = PG_GETARG_NAME(3);
	vtx_name_str = NameStr(*vtx_label_name);

	/* Check if vertex and edge label are same */
	if (strcmp(vtx_name_str, edge_name_str) == 0)
	{
	ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
	errmsg("vertex and edge label can not be same")));
	}
	}

	if (!graph_exists(graph_name_str))
	{
	DirectFunctionCall1(create_graph, CStringGetDatum(graph_name->data));
	}

	graph_oid = get_graph_oid(graph_name_str);

	if (!PG_ARGISNULL(3))
	{
	/* Check if label with the input name already exists */
	if (!label_exists(vtx_name_str, graph_oid))
	{
	DirectFunctionCall2(create_vlabel,
	CStringGetDatum(graph_name->data),
	CStringGetDatum(vtx_label_name->data));
	}
	}

	if (!label_exists(edge_name_str, graph_oid))
	{
	DirectFunctionCall2(create_elabel,
	CStringGetDatum(graph_name->data),
	CStringGetDatum(edge_label_name->data));
	}

	vtx_label_id = get_label_id(vtx_name_str, graph_oid);
	edge_label_id = get_label_id(edge_name_str, graph_oid);

	graph_cache = search_graph_name_cache(graph_name_str);
	vertex_cache = search_label_name_graph_cache(vtx_name_str, graph_oid);
	edge_cache = search_label_name_graph_cache(edge_name_str, graph_oid);

	nsp_id = graph_cache->namespace;
	vtx_seq_name = &(vertex_cache->seq_name);
	vtx_seq_name_str = NameStr(*vtx_seq_name);

	edge_seq_name = &(edge_cache->seq_name);
	edge_seq_name_str = NameStr(*edge_seq_name);

	vtx_seq_id = get_relname_relid(vtx_seq_name_str, nsp_id);
	edge_seq_id = get_relname_relid(edge_seq_name_str, nsp_id);

	props = create_empty_agtype();

	/* Creating vertices*/
	for (i=(int64)1; i<=no_vertices; i++)
	{
	vid = nextval_internal(vtx_seq_id, true);
	object_graph_id = make_graphid(vtx_label_id, vid);
	insert_vertex_simple(graph_oid, vtx_name_str, object_graph_id, props);
	}

	lid = vid;

	/* Creating edges*/
	for (i = 1; i<=no_vertices-1; i++)
	{
	start_vid = lid-no_vertices+i;
	for(j=i+1; j<=no_vertices; j++)
	{
	end_vid = lid-no_vertices+j;
	eid = nextval_internal(edge_seq_id, true);
	object_graph_id = make_graphid(edge_label_id, eid);

	start_vertex_graph_id = make_graphid(vtx_label_id, start_vid);
	end_vertex_graph_id = make_graphid(vtx_label_id, end_vid);

	insert_edge_simple(graph_oid, edge_name_str, object_graph_id,
	start_vertex_graph_id, end_vertex_graph_id,
	props);
	}
	}
	PG_RETURN_VOID();
	}


	PG_FUNCTION_INFO_V1(age_create_barbell_graph);

	/*
	* The barbell graph is two complete graphs connected by a bridge path
	* Syntax:
	* ag_catalog.age_create_barbell_graph(graph_name Name,
	* m int,
	* n int,
	* vertex_label_name Name DEFAULT = NULL,
	* vertex_properties agtype DEFAULT = NULL,
	* edge_label_name Name DEFAULT = NULL,
	* edge_properties agtype DEFAULT = NULL)
	* Input:
	*
	* graph_name - Name of the graph to be created.
	* m - number of vertices in one complete graph.
	* n - number of vertices in the bridge path.
	* vertex_label_name - Name of the label to assign each vertex to.
	* vertex_properties - Property values to assign each vertex. Default is NULL
	* edge_label_name - Name of the label to assign each edge to.
	* edge_properties - Property values to assign each edge. Default is NULL
	*
	* https://en.wikipedia.org/wiki/Barbell_graph
	*/

	Datum age_create_barbell_graph(PG_FUNCTION_ARGS)
	{
	FunctionCallInfo arguments;
	Oid graph_oid;
	Name graph_name;
	char* graph_name_str;

	int64 start_node_index, end_node_index, nextval;

	Name node_label_name = NULL;
	int32 node_label_id;
	char* node_label_str;

	Name edge_label_name;
	int32 edge_label_id;
	char* edge_label_str;

	graphid object_graph_id;
	graphid start_node_graph_id;
	graphid end_node_graph_id;

	graph_cache_data* graph_cache;
	label_cache_data* edge_cache;

	agtype* properties = NULL;

	arguments = fcinfo;

	/* Checking for possible NULL arguments */
	/* Name graph_name */
	if (PG_ARGISNULL(0))
	{
	ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
	errmsg("Graph name cannot be NULL")));
	}

	graph_name = PG_GETARG_NAME(0);
	graph_name_str = NameStr(*graph_name);

	/* int graph size (number of nodes in each complete graph) */
	if (PG_ARGISNULL(1) && PG_GETARG_INT32(1) < 3)
	{
	ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
	errmsg("Graph size cannot be NULL or lower than 3")));
	}

	/*
	* int64 bridge_size: currently only stays at zero.
	* to do: implement bridge with variable number of nodes.
	*/
	if (PG_ARGISNULL(2) \|\| PG_GETARG_INT32(2) < 0 )
	{
	ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
	errmsg("Bridge size cannot be NULL or lower than 0")));
	}

	/* node label: if null, gets default label, which is "_ag_label_vertex" */
	if (PG_ARGISNULL(3))
	{
	namestrcpy(node_label_name, AG_DEFAULT_LABEL_VERTEX);
	}
	else
	{
	node_label_name = PG_GETARG_NAME(3);
	}
	node_label_str = NameStr(*node_label_name);

	/* Name edge_label */
	if (PG_ARGISNULL(5))
	{
	ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
	errmsg("edge label can not be NULL")));
	}

	edge_label_name = PG_GETARG_NAME(5);
	edge_label_str = NameStr(*edge_label_name);


	/* create two separate complete graphs */
	DirectFunctionCall4(create_complete_graph, arguments->args[0].value,
	arguments->args[1].value,
	arguments->args[5].value,
	arguments->args[3].value);
	DirectFunctionCall4(create_complete_graph, arguments->args[0].value,
	arguments->args[1].value,
	arguments->args[5].value,
	arguments->args[3].value);

	graph_oid = get_graph_oid(graph_name_str);
	node_label_id = get_label_id(node_label_str, graph_oid);
	edge_label_id = get_label_id(edge_label_str, graph_oid);

	/*
	* Fetching caches to get next values for graph id's, and access nodes
	* to be connected with edges.
	*/
	graph_cache = search_graph_name_cache(graph_name_str);
	edge_cache = search_label_name_graph_cache(edge_label_str,graph_oid);

	/* connect a node from each graph */
	/* first created node, from the first complete graph */
	start_node_index = 1;
	/* last created node, second graph */
	end_node_index = arguments->args[1].value*2;

	/* next index to be assigned to a node or edge */
	nextval = get_nextval_internal(graph_cache, edge_cache);

	/* build the graph id's of the edge to be created */
	object_graph_id = make_graphid(edge_label_id, nextval);
	start_node_graph_id = make_graphid(node_label_id, start_node_index);
	end_node_graph_id = make_graphid(node_label_id, end_node_index);
	properties = create_empty_agtype();

	/* connect two nodes */
	insert_edge_simple(graph_oid, edge_label_str,
	object_graph_id, start_node_graph_id,
	end_node_graph_id, properties);

	PG_RETURN_VOID();
	}