first chunk of NGSI node type implementation

documentation/Clients.md

@@ -4,6 +4,7 @@
 @subpage opal
 @subpage file
 @subpage socket
+@subpage ngsi
 
 Every server needs clients which act as sinks / sources for simulation data. In case of S2SS these clients are called _nodes_.
 
@@ -13,5 +14,6 @@ Take a look at the `clients/` directory for them:
  - RTDS via GTFPGA and PCIexpress
  - OPAL via Asynchronous Process and UDP
  - OPAL via Asynchronous Process and Shared memory
+ - NGSI 9/10 (FIRWARE context broker)
  - Labview (*planned*)
  - Simulink (*planned*)

server/etc/example.conf

@@ -111,6 +111,21 @@ nodes = {
 		id = "1ab8:4005",			# The PCIe vendor:device ID (see third column in 'lspci -n' output)
 		
 		rate = 1
+	},
+	ngsi_node = {
+		type = "ngsi",
+		
+	### The following settings are specific to the gtfpga node-type!! ###
+		endpoint = "http://46.101.131.212:1026/v1",	# The HTTP / REST endpoint of the FIRWARE context broker
+
+		mapping = [					# Format: "entityID(entityType).AttributeId(AttributeType)"
+			"rtds_sub1(voltage3).v1(float),
+			"rtds_sub1(voltage3).v2(float)",
+			"rtds_sub1(voltage3).v3(float)",
+			"rtds_sub2(power3).p1(float)",
+			"rtds_sub2(power3).p2(float)",
+			"rtds_sub2(power3).p3(float)"
+		]
 	}
 };
 

server/include/ngsi.h

@@ -0,0 +1,86 @@
+/** Node type: NGSI 9/10 (FIWARE context broker)
+ *
+ * This file implements the NGSI protocol as a node type.
+ *
+ * @see https://forge.fiware.org/plugins/mediawiki/wiki/fiware/index.php/FI-WARE_NGSI-10_Open_RESTful_API_Specification
+ * @file
+ * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
+ * @copyright 2014-2015, Institute for Automation of Complex Power Systems, EONERC
+ *   This file is part of S2SS. All Rights Reserved. Proprietary and confidential.
+ *   Unauthorized copying of this file, via any medium is strictly prohibited. 
+ */
+/**
+ * @addtogroup ngsi FIRWARE NGSI 9/10 RESTful HTTP API
+ * @ingroup node
+ * @{
+ **********************************************************************************/
+
+#ifndef _NGSI_H_
+#define _NGSI_H_
+
+#include <curl/curl.h>
+
+#include "list.h"
+#include "config.h"
+#include "msg.h"
+#include "cfg.h"
+#include "node.h"
+
+struct node;
+
+struct ngsi_attribute {
+	char *name;
+	char *type;
+	
+	int index;
+};
+
+struct ngsi_entity {
+	char *name;
+	char *type;
+
+	struct list attributes;
+	struct list metadata;
+};
+
+struct ngsi {
+	char *endpoint;
+	char *token;
+	
+	struct list entities;
+	
+	struct curl_slist *headers;	
+	CURL *curl;
+};
+
+/** Initialize global NGSI settings and maps shared memory regions.
+ *
+ * @see node_vtable::init
+ */
+int ngsi_init(int argc, char *argv[], struct settings *set);
+
+/** Free global NGSI settings and unmaps shared memory regions.
+ *
+ * @see node_vtable::deinit
+ */
+int ngsi_deinit();
+
+/** @see node_vtable::parse */
+int ngsi_parse(config_setting_t *cfg, struct node *n);
+
+/** @see node_vtable::print */
+int ngsi_print(struct node *n, char *buf, int len);
+
+/** @see node_vtable::open */
+int ngsi_open(struct node *n);
+
+/** @see node_vtable::close */
+int ngsi_close(struct node *n);
+
+/** @see node_vtable::read */
+int ngsi_read(struct node *n, struct msg *pool, int poolsize, int first, int cnt);
+
+/** @see node_vtable::write */
+int ngsi_write(struct node *n, struct msg *pool, int poolsize, int first, int cnt);
+
+#endif /** _NGSI_H_ @} */

server/src/ngsi.c

@@ -0,0 +1,179 @@
+/** Node type: FIWARE NGSI 9/10
+ *
+ * This file implements the NGSI protocol as a node type.
+ *
+ * @see https://forge.fiware.org/plugins/mediawiki/wiki/fiware/index.php/FI-WARE_NGSI-10_Open_RESTful_API_Specification
+ * @author Steffen Vogel <stvogel@eonerc.rwth-aachen.de>
+ * @copyright 2014-2015, Institute for Automation of Complex Power Systems, EONERC
+ *   This file is part of S2SS. All Rights Reserved. Proprietary and confidential.
+ *   Unauthorized copying of this file, via any medium is strictly prohibited. 
+ **********************************************************************************/
+
+#include <curl/curl.h>
+#include <jansson.h>
+
+#include "ngsi.h"
+#include "utils.h"
+
+/* NGSI Entity, Attribute & Metadata structure */
+
+void ngsi_entity_dtor(void *ptr)
+{
+	struct ngsi_entity *entity = ptr;
+
+	list_destroy(&entity->attributes);
+	list_destroy(&entity->metadata);
+
+	free(entity->name);
+	free(entity->type);
+}
+
+void ngsi_attribute_dtor(void *ptr)
+{
+	struct ngsi_attribute *entity = ptr;
+
+	free(entity->name);
+	free(entity->type);
+}
+
+struct ngsi_entity * ngsi_entity()
+{
+	struct ngsi_entity *entity = alloc(sizeof(struct ngsi_entity));
+	
+	list_init(&entity->attributes, ngsi_attribute_dtor);
+	list_init(&entity->metadata, ngsi_attribute_dtor);
+
+	return entity;
+}
+
+/* Node type */
+
+int ngsi_init(int argc, char *argv[], struct settings *set)
+{
+	 curl_global_init(CURL_GLOBAL_ALL);
+}
+
+int ngsi_deinit()
+{
+	curl_global_cleanup();
+}
+
+int ngsi_parse(config_setting_t *cfg, struct node *n)
+{
+	struct ngsi *i = n->ngsi;
+
+	config_setting_t *mapping =  config_setting_get_member(cfg, "mapping");
+	if (!mapping || !config_setting_is_array(mapping))
+		cerror(cfg, "Missing entity.attribute mapping for node '%s", n->name);
+	
+	for (int i = 0; i < config_setting_length(mapping); i++) {
+		const char *token = config_setting_get_string_elem(mapping, i);
+		if (token) {
+			if (sscanf(token, "%ms(%ms).%ms", &entity, &type, &attribue) != 2)
+				cerror(mapping, "Invalid entity.attribute token: '%s'", token);
+		
+			
+		}
+		cerror(mapping, "Invalid entity.attribute token");
+	}
+}
+
+int ngsi_print(struct node *n, char *buf, int len)
+{
+	struct ngsi *i = n->ngsi;
+	
+	return snprintf(buf, len, "endpoint=%s, token=%s, entities=%u",
+		i->endpoint, i->token, i->entities);
+}
+
+int ngsi_open(struct node *n)
+{
+	char buf[128];
+	struct ngsi *i = n->ngsi;
+
+	i->curl = curl_easy_init();
+	i->headers = NULL:
+	
+	if (i->token) {
+		snprintf(buf, sizeof(buf), "Auth-Token: %s", i->token);
+		i->headers = curl_slist_append(i->headers, buf);
+	}
+	
+	i->headers = curl_slist_append(i->headers, "User-Agent: S2SS " VERSION);
+	i->headers = curl_slist_append(i->headers, "Content-Type: application/json");
+	
+	snprintf(buf, sizeof(buf), "%s/v1/%s")
+
+	curl_easy_setopt(i->curl, CURLOPT_URL, url);
+	curl_easy_setopt(i->curl, CURLOPT_POSTFIELDSIZE, -1);
+	curl_easy_setopt(i->curl, CURLOPT_HTTPHEADER, i->headers);
+	
+	/* Create entity */
+	char *post = ngsi_update_context(n, "APPEND");
+	
+	return 0;
+}
+
+int ngsi_close(struct node *n)
+{
+	struct ngsi *i = n->ngsi;
+	
+	curl_easy_cleanup(i->curl);
+	curl_slist_free_all(i->headers);
+	
+	return 0;
+}
+
+static int ngsi_query_context(struct node *n)
+{
+	struct ngsi *i = n->ngsi;
+	
+	return 0;
+}
+
+static char * ngsi_update_context(struct node *n, char *action)
+{
+	struct ngsi *i = n->ngsi;
+	
+	json_t *root = json_object();
+	json_t *elements = json_array();
+	
+	for (int i = 0; i < i->entities; i++) {
+		json_t *entity = json_object();
+		json_t *attributes = json_object();
+
+		json_object_set(entity, "type", json_string("Room"));
+		json_object_set(entity, "isPattern", json_false());
+		json_object_set(entity, "id", json_string("Room1"));
+	}
+	
+	json_object_set(root, "contextElements", conextElements);
+	json_object_set(root, "updateAction", json_string(action));
+	
+	return json_dumps(root, JSON_COMPACT);
+}
+
+int ngsi_read(struct node *n, struct msg *pool, int poolsize, int first, int cnt)
+{
+	struct ngsi *i = n->ngsi;
+	
+	return -1; /** @todo not yet implemented */
+}
+
+int ngsi_write(struct node *n, struct msg *pool, int poolsize, int first, int cnt)
+{
+	struct ngsi *i = n->ngsi;
+	
+	long result;
+	char *post = ngsi_update_context(n, "UPDATE");
+	
+	curl_easy_setopt(i->curl, CURLOPT_COPYPOSTFIELDS, post);
+	
+	curl_easy_perform(i->curl);
+	
+	curl_easy_getinfo(i->curl, CURLINFO_RESPONSE_CODE, &result);
+	
+	return result == 200 ? 1 : 0
+}
+
+REGISTER_NODE_TYPE(NGSI, "ngsi", ngsi)

server/src/node.c

@@ -108,6 +108,11 @@ struct node * node_create()
 void node_destroy(struct node *n)
 {
 	switch (n->vt->type) {
+#ifdef ENABLE_NGSI
+		case NGSI:
+			list_destroy(n->ngsi->entities);
+		break;
+#endif
 #ifdef ENABLE_SOCKET
 		case BSD_SOCKET:
 			rtnl_qdisc_put(n->socket->tc_qdisc);