From 0631be19cb7a8334f0e159fbe6bd1be9286f6595 Mon Sep 17 00:00:00 2001
From: Olof hagsand <olof@hagsand.se>
Date: Tue, 18 Sep 2018 22:49:29 +0200
Subject: [PATCH] * Notification event streams enhancements   * Yang 1.1
 notification support   * Event stream discovery support according to RFC 5277
 Sec 3.2.5.1 (netconf) and RFC 8040 (restconf)

---
 CHANGELOG.md                                  |   3 +
 apps/backend/backend_client.c                 | 107 +++++++++++--
 apps/backend/backend_main.c                   |  10 +-
 apps/backend/clixon_backend_handle.c          |   2 +
 apps/cli/cli_handle.c                         |  12 +-
 apps/restconf/README.md                       |   4 +-
 lib/clixon/clixon.h.in                        |   1 +
 lib/clixon/clixon_handle.h                    |   5 +
 lib/clixon/clixon_yang.h                      |   1 +
 lib/src/Makefile.in                           |   2 +-
 lib/src/clixon_handle.c                       |  33 +++-
 lib/src/clixon_yang.c                         |  52 +++++-
 lib/src/clixon_yang_parse.y                   |  37 ++++-
 test/test_event.sh                            | 117 ++++++++++++++
 yang/Makefile.in                              |   1 +
 yang/ietf-restconf-monitoring@2017-01-26.yang | 149 ++++++++++++++++++
 16 files changed, 502 insertions(+), 34 deletions(-)
 create mode 100755 test/test_event.sh
 create mode 100644 yang/ietf-restconf-monitoring@2017-01-26.yang

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0f780790..0a46eab7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,9 @@
 ### Major New features
 
 ### API changes on existing features (you may need to change your code)
+* Notification event streams enhancements
+  * Yang 1.1 notification support
+  * Event stream discovery support according to RFC 5277 Sec 3.2.5.1 (netconf) and RFC 8040 (restconf)
 * clixon_restconf and clixon_netconf now take -D <level> as command-line option instead of just -D
   * This aligns to clixon_cli and clixon_backend
 * Application command option -S to clixon_netconf is obsolete. Use `clixon_netconf -l s` instead.
diff --git a/apps/backend/backend_client.c b/apps/backend/backend_client.c
index 224b371d..71714e68 100644
--- a/apps/backend/backend_client.c
+++ b/apps/backend/backend_client.c
@@ -99,20 +99,10 @@ client_subscription_add(struct client_entry *ce,
     return su;
 }
 
-static struct client_entry *
-ce_find_bypid(struct client_entry *ce_list, int pid)
-{
-    struct client_entry *ce;
-
-    for (ce = ce_list; ce; ce = ce->ce_next)
-	if (ce->ce_pid == pid)
-	    return ce;
-    return NULL;
-}
-
+/*! Delete stream subscription from client subscription list */
 static int
 client_subscription_delete(struct client_entry *ce, 
-		    struct client_subscription *su0)
+			   struct client_subscription *su0)
 {
     struct client_subscription   *su;
     struct client_subscription  **su_prev;
@@ -134,7 +124,8 @@ client_subscription_delete(struct client_entry *ce,
 
 #ifdef notused /* xxx */
 static struct client_subscription *
-client_subscription_find(struct client_entry *ce, char *stream)
+client_subscription_find(struct client_entry *ce,
+			 char *stream)
 {
     struct client_subscription   *su = NULL;
 
@@ -146,6 +137,18 @@ client_subscription_find(struct client_entry *ce, char *stream)
 }
 #endif 
 
+static struct client_entry *
+ce_find_bypid(struct client_entry *ce_list,
+	      int pid)
+{
+    struct client_entry *ce;
+
+    for (ce = ce_list; ce; ce = ce->ce_next)
+	if (ce->ce_pid == pid)
+	    return ce;
+    return NULL;
+}
+
 /*! Remove client entry state
  * Close down everything wrt clients (eg sockets, subscriptions)
  * Finally actually remove client struct in handle
@@ -258,6 +261,79 @@ from_client_get_config(clicon_handle h,
     return retval;
 }
 
+static int
+client_get_streams(clicon_handle        h,
+		   char                *xpath,
+		   cxobj              **xtop)
+{
+    int            retval = -1;
+    cxobj         *x = NULL;
+    cxobj         *xc;
+    char          *reason = NULL;
+    yang_spec     *yspec;
+    cbuf          *cb;
+
+    if ((yspec =  clicon_dbspec_yang(h)) == NULL){
+	clicon_err(OE_YANG, ENOENT, "No yang spec");
+	goto done;
+    }
+    if (*xtop==NULL){
+	clicon_err(OE_CFG, ENOENT, "XML tree expected");
+	goto done;
+    }
+    if ((cb = cbuf_new()) == NULL){
+	clicon_err(OE_UNIX, 0, "clicon buffer");
+	goto done;
+    }
+    cprintf(cb,"<restconf-state xmlns=\"urn:ietf:params:xml:ns:yang:ietf-restconf-monitoring\">");
+    if (stream_get_xml(h, cb) < 0)
+	goto done;
+    cprintf(cb,"</restconf-state>");
+    /* XXX. yspec */
+    if (xml_parse_string(cbuf_get(cb), NULL, &x) < 0)
+	goto done;
+    if (xml_merge(*xtop, x, yspec, &reason) < 0)
+	goto done;
+    if (reason){
+	while ((xc = xml_child_i(*xtop, 0)) != NULL)
+	    xml_purge(xc);	    
+	if (netconf_operation_failed_xml(xtop, "rpc", reason)< 0)
+	    goto done;
+	goto ok;
+    }
+#ifdef notyet
+    /* Code complex to filter out anything that is outside of xpath */
+    if (xpath_vec(*xtop, "%s", &xvec, &xlen, xpath?xpath:"/") < 0)
+	goto done;
+
+    /* If vectors are specified then mark the nodes found and
+     * then filter out everything else,
+     * otherwise return complete tree.
+     */
+    if (xvec != NULL){
+	for (i=0; i<xlen; i++)
+	    xml_flag_set(xvec[i], XML_FLAG_MARK);
+    }
+    /* Remove everything that is not marked */
+    if (!xml_flag(*xtop, XML_FLAG_MARK))
+	if (xml_tree_prune_flagged_sub(*xtop, XML_FLAG_MARK, 1, NULL) < 0)
+	    goto done;
+    /* reset flag */
+    if (xml_apply(*xtop, CX_ELMNT, (xml_applyfn_t*)xml_flag_reset, (void*)XML_FLAG_MARK) < 0)
+	goto done;
+#endif
+ ok:
+    retval = 0;
+ done:
+    if (cb)
+	cbuf_free(cb);
+    if (reason)
+	free(reason);
+    if (x)
+	xml_free(x);
+    return retval;
+}
+
 /*! Internal message: get
  * 
  * @param[in]  h     Clicon handle
@@ -288,6 +364,11 @@ from_client_get(clicon_handle h,
     }
     /* Get state data from plugins as defined by plugin_statedata(), if any */
     assert(xret);
+
+#if 1 /* get netconf state data */
+    if ((ret = client_get_streams(h, selector, &xret)) < 0)
+	goto done;
+#endif
     clicon_err_reset();
     if ((ret = clixon_plugin_statedata(h, selector, &xret)) < 0)
 	goto done;
diff --git a/apps/backend/backend_main.c b/apps/backend/backend_main.c
index 07617e93..fd128941 100644
--- a/apps/backend/backend_main.c
+++ b/apps/backend/backend_main.c
@@ -756,6 +756,11 @@ main(int    argc,
 	return -1;
     }
 
+    if (stream_register(h, "NETCONF", "default NETCONF event stream") < 0)
+	goto done;
+    if (stream_register(h, "CLICON", "Clicon logs") < 0)
+	goto done;
+	
     if ((xmldb_plugin = clicon_xmldb_plugin(h)) == NULL){
 	clicon_log(LOG_ERR, "No xmldb plugin given (specify option CLICON_XMLDB_PLUGIN).\n"); 
 	goto done;
@@ -765,10 +770,11 @@ main(int    argc,
     /* Connect to plugin to get a handle */
     if (xmldb_connect(h) < 0)
 	goto done;
-    /* Parse db spec file */
+    /* Read and parse application yang specification */
     if (yang_spec_main(h) == NULL)
 	goto done;
-
+    if (yang_spec_append(h, CLIXON_DATADIR, "ietf-restconf-monitoring", NULL)< 0)
+	goto done;
     /* Set options: database dir and yangspec (could be hidden in connect?)*/
     if (xmldb_setopt(h, "dbdir", clicon_xmldb_dir(h)) < 0)
 	goto done;
diff --git a/apps/backend/clixon_backend_handle.c b/apps/backend/clixon_backend_handle.c
index 1fc397d8..feb7969c 100644
--- a/apps/backend/clixon_backend_handle.c
+++ b/apps/backend/clixon_backend_handle.c
@@ -86,6 +86,8 @@ struct backend_handle {
     int                      bh_magic;     /* magic (HDR)*/
     clicon_hash_t           *bh_copt;      /* clicon option list (HDR) */
     clicon_hash_t           *bh_data;      /* internal clicon data (HDR) */
+    event_stream_t          *ch_stream;   /* notification streams, see clixon_stream.[ch] */
+    
     /* ------ end of common handle ------ */
     struct client_entry     *bh_ce_list;   /* The client list */
     int                      bh_ce_nr;     /* Number of clients, just increment */
diff --git a/apps/cli/cli_handle.c b/apps/cli/cli_handle.c
index 1690a143..58e03948 100644
--- a/apps/cli/cli_handle.c
+++ b/apps/cli/cli_handle.c
@@ -76,14 +76,14 @@
  * @see struct clicon_handle, struct backend_handle
  */
 struct cli_handle {
-    int                      cl_magic;    /* magic (HDR)*/
-    clicon_hash_t           *cl_copt;     /* clicon option list (HDR) */
-    clicon_hash_t           *cl_data;     /* internal clicon data (HDR) */
+    int             cl_magic;    /* magic (HDR)*/
+    clicon_hash_t  *cl_copt;     /* clicon option list (HDR) */
+    clicon_hash_t  *cl_data;     /* internal clicon data (HDR) */
+    event_stream_t *cl_stream;   /* notification streams, see clixon_stream.[ch] */
     /* ------ end of common handle ------ */
-    cligen_handle            cl_cligen;   /* cligen handle */
-
-    cli_syntax_t *cl_stx;	           /* syntax structure */
 
+    cligen_handle   cl_cligen;   /* cligen handle */
+    cli_syntax_t   *cl_stx;	/* syntax structure */
 };
 
 /*! Return a clicon handle for other CLICON API calls
diff --git a/apps/restconf/README.md b/apps/restconf/README.md
index f3f0c71f..2086634b 100644
--- a/apps/restconf/README.md
+++ b/apps/restconf/README.md
@@ -7,11 +7,13 @@ Ensure www-data is member of the CLICON_SOCK_GROUP (default clicon). If not, add
   sudo usermod -a -G clicon www-data
 ```
 
+This implementation uses FastCGI, see http://www.mit.edu/~yandros/doc/specs/fcgi-spec.html.
+
 Define nginx config file: /etc/nginx/sites-available/default
 ```
 server {
   ...
-  location /restconf {
+  location / {
     root /usr/share/nginx/html/restconf;
     fastcgi_pass unix:/www-data/fastcgi_restconf.sock;
     include fastcgi_params;
diff --git a/lib/clixon/clixon.h.in b/lib/clixon/clixon.h.in
index f3901788..cd21a594 100644
--- a/lib/clixon/clixon.h.in
+++ b/lib/clixon/clixon.h.in
@@ -68,6 +68,7 @@
 #include <clixon/clixon_queue.h>
 #include <clixon/clixon_hash.h>
 #include <clixon/clixon_handle.h>
+#include <clixon/clixon_stream.h>
 #include <clixon/clixon_yang.h>
 #include <clixon/clixon_yang_type.h>
 #include <clixon/clixon_event.h>
diff --git a/lib/clixon/clixon_handle.h b/lib/clixon/clixon_handle.h
index 897560c3..e0ebc07e 100644
--- a/lib/clixon/clixon_handle.h
+++ b/lib/clixon/clixon_handle.h
@@ -74,4 +74,9 @@ clicon_hash_t *clicon_options(clicon_handle h);
 /* Return internal clicon data (hash-array) given a handle.*/
 clicon_hash_t *clicon_data(clicon_handle h);
 
+/* Return internal stream hash-array given a handle.*/
+struct event_stream *clicon_stream(clicon_handle h);
+struct event_stream;
+int clicon_stream_append(clicon_handle h, struct event_stream *es);
+
 #endif  /* _CLIXON_HANDLE_H_ */
diff --git a/lib/clixon/clixon_yang.h b/lib/clixon/clixon_yang.h
index 49b5c5da..13ad5758 100644
--- a/lib/clixon/clixon_yang.h
+++ b/lib/clixon/clixon_yang.h
@@ -274,6 +274,7 @@ int        yang_mandatory(yang_stmt *ys);
 int        yang_config(yang_stmt *ys);
 yang_spec *yang_spec_netconf(clicon_handle h);
 yang_spec *yang_spec_main(clicon_handle h);
+int        yang_spec_append(clicon_handle h, char *yang_dir, char *yang_module, char *yang_revision);
 cvec      *yang_arg2cvec(yang_stmt *ys, char *delimi);
 int        yang_key_match(yang_node *yn, char *name);
 
diff --git a/lib/src/Makefile.in b/lib/src/Makefile.in
index 23126689..8e80f61a 100644
--- a/lib/src/Makefile.in
+++ b/lib/src/Makefile.in
@@ -73,7 +73,7 @@ SRC     = clixon_sig.c clixon_log.c clixon_err.c clixon_event.c \
 	  clixon_hash.c clixon_options.c clixon_plugin.c \
 	  clixon_proto.c clixon_proto_client.c \
 	  clixon_xpath.c clixon_xpath_ctx.c clixon_sha1.c \
-	  clixon_xml_db.c clixon_netconf_lib.c
+	  clixon_xml_db.c clixon_netconf_lib.c clixon_stream.c
 
 YACCOBJS := lex.clixon_xml_parse.o clixon_xml_parse.tab.o \
 	    lex.clixon_yang_parse.o  clixon_yang_parse.tab.o \
diff --git a/lib/src/clixon_handle.c b/lib/src/clixon_handle.c
index edac1382..31158ddc 100644
--- a/lib/src/clixon_handle.c
+++ b/lib/src/clixon_handle.c
@@ -53,6 +53,8 @@
 #include "clixon_log.h"
 #include "clixon_err.h"
 #include "clixon_yang.h"
+#include "clixon_xml.h"
+#include "clixon_stream.h"
 #include "clixon_options.h"
 
 #define CLICON_MAGIC 0x99aafabe
@@ -65,9 +67,10 @@
  * @see struct backend_handle
  */
 struct clicon_handle {
-    int                ch_magic;    /* magic (HDR) */
-    clicon_hash_t     *ch_copt;     /* clicon option list (HDR) */
-    clicon_hash_t     *ch_data;     /* internal clicon data (HDR) */
+    int               ch_magic;    /* magic (HDR) */
+    clicon_hash_t    *ch_copt;     /* clicon option list (HDR) */
+    clicon_hash_t    *ch_data;     /* internal clicon data (HDR) Unclear why two? */
+    event_stream_t   *ch_stream;   /* notification streams, see clixon_stream.[ch] */
 };
 
 /*! Internal call to allocate a CLICON handle. 
@@ -133,6 +136,7 @@ clicon_handle_exit(clicon_handle h)
 	hash_free(copt);
     if ((data = clicon_data(h)) != NULL)
 	hash_free(data);
+    stream_free(clicon_stream(h));
     free(ch);
     return 0;
 }
@@ -172,3 +176,26 @@ clicon_data(clicon_handle h)
 
     return ch->ch_data;
 }
+
+/*! Return stream hash-array given a clicon handle.
+ * @param[in]  h        Clicon handle
+ */
+event_stream_t *
+clicon_stream(clicon_handle h)
+{
+    struct clicon_handle *ch = handle(h);
+
+    return ch->ch_stream;
+}
+
+int
+clicon_stream_append(clicon_handle h,
+		     event_stream_t *es)
+{
+    struct clicon_handle *ch = handle(h);
+    event_stream_t      **ep;
+
+    for (ep = &ch->ch_stream; (*ep); ep=&(*ep)->es_next);
+    *ep = es;
+    return 0;
+}
diff --git a/lib/src/clixon_yang.c b/lib/src/clixon_yang.c
index d6336da9..acee080c 100644
--- a/lib/src/clixon_yang.c
+++ b/lib/src/clixon_yang.c
@@ -1914,7 +1914,7 @@ ys_schemanode_check(yang_stmt *ys,
  * @param[in] yang_dir Directory where all YANG module files reside (except mainfile)
  * @param[in] mainmod  Name of main YANG module. Or absolute file name.
  * @param[in] revision Main module revision date string or NULL
- * @param[out] ysp     Yang specification. Should ave been created by caller using yspec_new
+ * @param[out] ysp     Yang specification. Should have been created by caller using yspec_new
  * @retval 0  Everything OK
  * @retval -1 Error encountered
  * The database symbols are inserted in alphabetical order.
@@ -2388,7 +2388,9 @@ yang_config(yang_stmt *ys)
     return 1;
 }
 
-/*! Parse netconf yang spec, used by netconf client and as internal protocol */
+/*! Parse netconf yang spec, used by netconf client and as internal protocol 
+ * @note not used yet - unfinnisshed code
+ */
 yang_spec *
 yang_spec_netconf(clicon_handle h)
 {
@@ -2405,18 +2407,16 @@ yang_spec_netconf(clicon_handle h)
     return yspec;
 }
 
-/*! Read, parse and save application yang specification as option
+/*! Parse yang specification and its dependencies recursively and return
  * @param[in] h          clicon handle
- * @param[in] f          file to print to (if printspec enabled)
- * @param[in] printspec  print database (YANG) specification as read from file
  */
 yang_spec*
 yang_spec_main(clicon_handle h)
 {
     yang_spec      *yspec = NULL;
-    char           *yang_dir;
     char           *yang_module;
     char           *yang_revision;
+    char           *yang_dir;
 
     if ((yang_dir = clicon_yang_dir(h)) == NULL){
 	clicon_err(OE_FATAL, 0, "CLICON_YANG_DIR option not set");
@@ -2439,6 +2439,46 @@ yang_spec_main(clicon_handle h)
     return yspec;
 }
 
+/*! Parse yang specification, its dependencies, and append to default yang spec
+ * yang_spec_main should have been called first.
+ * @param[in] h             clicon handle
+ * @param[in] yang_dir      Directory, either system-wide or application-specific
+ * @param[in] yang_module   Name of module
+ * @param[in] yang_revision Revision, or NULL
+ * @see yang_spec_main
+ */
+int
+yang_spec_append(clicon_handle h,
+		 char         *yang_dir,
+		 char         *yang_module,
+		 char         *yang_revision)
+{
+    int        retval = -1;
+    yang_spec *yspec;
+    yang_spec *yspec0;
+    yang_stmt *ym = NULL; /* module */
+
+    if ((yspec0 = clicon_dbspec_yang(h)) == NULL){
+	clicon_err(OE_YANG, ENOENT, "yang spec not found");
+	goto done;
+    }
+    if ((yspec = yspec_new()) == NULL)
+	goto done;
+    if (yang_parse(h, yang_dir, yang_module, yang_revision, yspec) < 0){
+	yspec_free(yspec); yspec = NULL;
+	goto done;
+    }
+    while ((ym = yn_each((yang_node*)yspec, ym)) != NULL)
+	if (yn_insert((yang_node*)yspec0, ym) < 0)
+	    goto done;
+    yspec->yp_len = 0;
+    retval = 0;
+ done:
+    if (yspec)
+	yspec_free(yspec);
+    return retval;
+}
+
 /*! Given a yang node, translate the argument string to a cv vector
  *
  * @param[in]  ys         Yang statement 
diff --git a/lib/src/clixon_yang_parse.y b/lib/src/clixon_yang_parse.y
index 2dc7d8f2..8fd7ed38 100644
--- a/lib/src/clixon_yang_parse.y
+++ b/lib/src/clixon_yang_parse.y
@@ -485,6 +485,7 @@ body_stmt     : extension_stmt       { clicon_debug(2,"body-stmt -> extension-st
               | data_def_stmt        { clicon_debug(2,"body-stmt -> data-def-stmt");}
               | augment_stmt         { clicon_debug(2,"body-stmt -> augment-stmt");}
               | rpc_stmt             { clicon_debug(2,"body-stmt -> rpc-stmt");}
+              | notification_stmt    { clicon_debug(2,"body-stmt -> notification-stmt");}
               ;
 
 data_def_stmt : container_stmt       { clicon_debug(2,"data-def-stmt -> container-stmt");}
@@ -521,7 +522,8 @@ container_substmt : when_stmt       { clicon_debug(2,"container-substmt -> when-
               | reference_stmt      { clicon_debug(2,"container-substmt -> reference-stmt"); }
               | typedef_stmt        { clicon_debug(2,"container-substmt -> typedef-stmt"); }
               | grouping_stmt       { clicon_debug(2,"container-substmt -> grouping-stmt"); }
-              | data_def_stmt   { clicon_debug(2,"container-substmt -> data-def-stmt");} 
+              | data_def_stmt       { clicon_debug(2,"container-substmt -> data-def-stmt");}
+              | notification_stmt   { clicon_debug(2,"container-substmt -> notification-stmt");} 
               | unknown_stmt        { clicon_debug(2,"container-substmt -> unknown-stmt");} 
               |                     { clicon_debug(2,"container-substmt ->");} 
               ;
@@ -619,6 +621,7 @@ list_substmt  : when_stmt            { clicon_debug(2,"list-substmt -> when-stmt
               | typedef_stmt         { clicon_debug(2,"list-substmt -> typedef-stmt"); }
               | grouping_stmt        { clicon_debug(2,"list-substmt -> grouping-stmt"); }
               | data_def_stmt        { clicon_debug(2,"list-substmt -> data-def-stmt"); }
+              | notification_stmt    { clicon_debug(2,"list-substmt -> notification-stmt"); }
               | unknown_stmt         { clicon_debug(2,"list-substmt -> unknown-stmt");} 
               |                      { clicon_debug(2,"list-substmt -> "); }
               ;
@@ -792,7 +795,8 @@ augment_substmt : when_stmt          { clicon_debug(2,"augment-substmt -> when-s
               | description_stmt     { clicon_debug(2,"augment-substmt -> description-stmt"); }
               | reference_stmt       { clicon_debug(2,"augment-substmt -> reference-stmt"); }
               | data_def_stmt        { clicon_debug(2,"augment-substmt -> data-def-stmt"); }
-              | case_stmt            { clicon_debug(2,"augment-substmt -> case-stmt");} 
+              | case_stmt            { clicon_debug(2,"augment-substmt -> case-stmt");}
+              | notification_stmt    { clicon_debug(2,"augment-substmt -> notification-stmt");} 
               |                      { clicon_debug(2,"augment-substmt -> "); }
               ;
 
@@ -875,6 +879,34 @@ output_stmt  : K_OUTPUT  /* XXX reuse input-substatements since they are same */
               ;
 
 
+/* notification */
+notification_stmt : K_NOTIFICATION id_arg_str ';' 
+	                { if (ysp_add(_yy, Y_NOTIFICATION, $2, NULL) == NULL) _YYERROR("46"); 
+			   clicon_debug(2,"notification-stmt -> NOTIFICATION id-arg-str ;"); }
+                  | K_NOTIFICATION id_arg_str
+                        { if (ysp_add_push(_yy, Y_NOTIFICATION, $2) == NULL) _YYERROR("47"); }
+	            '{' notification_substmts '}' 
+                        { if (ystack_pop(_yy) < 0) _YYERROR("48");
+			     clicon_debug(2,"notification-stmt -> NOTIFICATION id-arg-str { notification-substmts }"); }
+                  ;
+
+notification_substmts : notification_substmts notification_substmt 
+                         { clicon_debug(2,"notification-substmts -> notification-substmts notification-substmt"); }
+                      | notification_substmt 
+                         { clicon_debug(2,"notification-substmts -> notification-substmt"); }
+                      ;
+
+notification_substmt : if_feature_stmt  { clicon_debug(2,"notification-substmt -> if-feature-stmt"); }
+                     | must_stmt        { clicon_debug(2,"notification-substmt -> must-stmt"); }
+                     | status_stmt      { clicon_debug(2,"notification-substmt -> status-stmt"); }
+                     | description_stmt { clicon_debug(2,"notification-substmt -> description-stmt"); }
+                     | reference_stmt   { clicon_debug(2,"notification-substmt -> reference-stmt"); }
+                     | typedef_stmt     { clicon_debug(2,"notification-substmt -> typedef-stmt"); }
+                     | grouping_stmt    { clicon_debug(2,"notification-substmt -> grouping-stmt"); }
+                     | data_def_stmt    { clicon_debug(2,"notification-substmt -> data-def-stmt"); }
+                     |                  { clicon_debug(2,"notification-substmt -> "); }
+                     ;
+
 /* Typedef */
 typedef_stmt  : K_TYPEDEF id_arg_str 
                           { if (ysp_add_push(_yy, Y_TYPEDEF, $2) == NULL) _YYERROR("46"); }
@@ -964,6 +996,7 @@ grouping_substmt : status_stmt          { clicon_debug(2,"grouping-substmt -> st
               | typedef_stmt         { clicon_debug(2,"grouping-substmt -> typedef-stmt"); }
               | grouping_stmt        { clicon_debug(2,"grouping-substmt -> grouping-stmt"); }
               | data_def_stmt        { clicon_debug(2,"grouping-substmt -> data-def-stmt"); }
+              | notification_stmt    { clicon_debug(2,"grouping-substmt -> notification-stmt"); }
               |                      { clicon_debug(2,"grouping-substmt -> "); }
               ;
 
diff --git a/test/test_event.sh b/test/test_event.sh
new file mode 100755
index 00000000..8bcd9c46
--- /dev/null
+++ b/test/test_event.sh
@@ -0,0 +1,117 @@
+#!/bin/bash
+# Restconf basic functionality
+# Assume http server setup, such as nginx described in apps/restconf/README.md
+APPNAME=example
+# include err() and new() functions and creates $dir
+. ./lib.sh
+cfg=$dir/conf.xml
+fyang=$dir/restconf.yang
+xml=$dir/xml.xml
+
+#  <CLICON_YANG_MODULE_MAIN>example</CLICON_YANG_MODULE_MAIN>
+cat <<EOF > $cfg
+<config>
+  <CLICON_CONFIGFILE>$cfg</CLICON_CONFIGFILE>
+  <CLICON_YANG_DIR>/usr/local/share/clixon</CLICON_YANG_DIR>
+  <CLICON_YANG_MODULE_MAIN>$fyang</CLICON_YANG_MODULE_MAIN>
+  <CLICON_RESTCONF_PRETTY>false</CLICON_RESTCONF_PRETTY>
+  <CLICON_SOCK>/usr/local/var/$APPNAME/$APPNAME.sock</CLICON_SOCK>
+  <CLICON_BACKEND_PIDFILE>$dir/restconf.pidfile</CLICON_BACKEND_PIDFILE>
+  <CLICON_XMLDB_DIR>/usr/local/var/$APPNAME</CLICON_XMLDB_DIR>
+  <CLICON_XMLDB_PLUGIN>/usr/local/lib/xmldb/text.so</CLICON_XMLDB_PLUGIN>
+  <CLICON_CLISPEC_DIR>/usr/local/lib/$APPNAME/clispec</CLICON_CLISPEC_DIR>
+  <CLICON_CLI_DIR>/usr/local/lib/$APPNAME/cli</CLICON_CLI_DIR>
+  <CLICON_CLI_MODE>$APPNAME</CLICON_CLI_MODE>
+</config>
+EOF
+
+# RFC5277 NETCONF Event Notifications
+cat <<EOF > $fyang
+     module example {
+       namespace "http://example.com/event/1.0";
+       prefix ex;
+
+       organization "Example, Inc.";
+       contact "support at example.com";
+       description "Example Notification Data Model Module.";
+       revision "2016-07-07" {
+         description "Initial version.";
+         reference "example.com document 2-9976.";
+       }
+
+       notification event {
+         description "Example notification event.";
+         leaf event-class {
+           type string;
+           description "Event class identifier.";
+         }
+         container reporting-entity {
+           description "Event specific information.";
+           leaf card {
+             type string;
+             description "Line card identifier.";
+           }
+         }
+         leaf severity {
+           type string;
+           description "Event severity description.";
+         }
+       }
+     }
+EOF
+
+# kill old backend (if any)
+new "kill old backend"
+sudo clixon_backend -zf $cfg
+if [ $? -ne 0 ]; then
+    err
+fi
+new "start backend -s init -f $cfg -y $fyang"
+sudo $clixon_backend -s init -f $cfg -y $fyang -D 1
+
+if [ $? -ne 0 ]; then
+    err
+fi
+
+new "kill old restconf daemon"
+sudo pkill -u www-data clixon_restconf
+
+new "start restconf daemon"
+sudo start-stop-daemon -S -q -o -b -x /www-data/clixon_restconf -d /www-data -c www-data -- -f $cfg # -D 1
+
+sleep 1
+
+new "restconf tests"
+
+# get the stream list using netconf
+new "netconf event stream discovery RFC5277 Sec 3.2.5"
+echo "$clixon_netconf -qf $cfg -y $fyang"
+expecteof "$clixon_netconf -qf $cfg -y $fyang" 0 '<rpc><get><filter type="xpath" selector="netconf/streams" xmlns="urn:ietf:params:xml:ns:netmod:notification"/></get></rpc>]]>]]>' '<rpc-reply><data><restconf-state><streams><stream><name>NETCONF</name><description>default NETCONF event stream</description><replay-support>false</replay-support></stream><stream><name>CLICON</name><description>Clicon logs</description><replay-support>false</replay-support></stream></streams></restconf-state></data></rpc-reply>]]>]]>'
+
+#expecteof "$clixon_netconf -qf $cfg -y $fyang" 0 '<rpc><get><filter type="subtree"><netconf xmlns="urn:ietf:params:xml:ns:netmod:notification"><streams/></netconf></filter></get></rpc>]]>]]>' '<rpc-reply><data><netconf><streams><stream><name>NETCONF</name>'
+
+#expecteof "$clixon_netconf -qf $cfg -y $fyang" 0 '<rpc message-id="101" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"><get><filter type="subtree"><netconf xmlns="urn:ietf:params:xml:ns:netmod:notification"><streams/></netconf></filter></get></rpc>]]>]]>' '<rpc-reply message-id="101" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"><data><netconf  xmlns="urn:ietf:params:xml:ns:netmod:notification"><streams><stream><name>NETCONF</name>'
+
+# get the stream list using restconf
+new "restconf GET datastore"
+#expectfn "curl -s -X GET http://localhost/restconf/data/ietf-restconf-monitoring:restconf-state/streams" 0 '{"data": {"cont1": {"interface": \[{"name": "local0","type": "regular"}\]}}}'
+
+new "netconf subscription"
+#expectwait "$clixon_netconf -qf $cfg -y $fyang" "<rpc><create-subscription><stream>ROUTING</stream></create-subscription></rpc>]]>]]>" "^<rpc-reply><ok/></rpc-reply>]]>]]><notification><event>Routing notification</event></notification>]]>]]>$" 30
+
+new "Kill restconf daemon"
+sudo pkill -u www-data clixon_restconf
+
+new "Kill backend"
+# Check if still alive
+pid=`pgrep clixon_backend`
+if [ -z "$pid" ]; then
+    err "backend already dead"
+fi
+# kill backend
+sudo clixon_backend -zf $cfg
+if [ $? -ne 0 ]; then
+    err "kill backend"
+fi
+
+rm -rf $dir
diff --git a/yang/Makefile.in b/yang/Makefile.in
index 469f026b..d5c0c7ea 100644
--- a/yang/Makefile.in
+++ b/yang/Makefile.in
@@ -45,6 +45,7 @@ YANGSPECS	+= ietf-netconf@2011-06-01.yang
 YANGSPECS	+= ietf-netconf-acm@2018-02-14.yang
 YANGSPECS	+= ietf-inet-types@2013-07-15.yang
 YANGSPECS	+= ietf-yang-types@2013-07-15.yang
+YANGSPECS	+= ietf-restconf-monitoring@2017-01-26.yang
 
 APPNAME	        = clixon  # subdir ehere these files are installed
 
diff --git a/yang/ietf-restconf-monitoring@2017-01-26.yang b/yang/ietf-restconf-monitoring@2017-01-26.yang
new file mode 100644
index 00000000..f114c9d0
--- /dev/null
+++ b/yang/ietf-restconf-monitoring@2017-01-26.yang
@@ -0,0 +1,149 @@
+module ietf-restconf-monitoring {
+    namespace "urn:ietf:params:xml:ns:yang:ietf-restconf-monitoring";
+    prefix "rcmon";
+
+    import ietf-yang-types { prefix yang; }
+    import ietf-inet-types { prefix inet; }
+
+    organization
+	"IETF NETCONF (Network Configuration) Working Group";
+
+    contact
+	"WG Web:   <https://datatracker.ietf.org/wg/netconf/>
+        WG List:  <mailto:netconf@ietf.org>
+
+        Author:   Andy Bierman
+                  <mailto:andy@yumaworks.com>
+
+        Author:   Martin Bjorklund
+                  <mailto:mbj@tail-f.com>
+
+        Author:   Kent Watsen
+                  <mailto:kwatsen@juniper.net>";
+
+    description
+	"This module contains monitoring information for the
+        RESTCONF protocol.
+
+        Copyright (c) 2017 IETF Trust and the persons identified as
+        authors of the code.  All rights reserved.
+
+        Redistribution and use in source and binary forms, with or
+        without modification, is permitted pursuant to, and subject
+        to the license terms contained in, the Simplified BSD License
+        set forth in Section 4.c of the IETF Trust's Legal Provisions
+        Relating to IETF Documents
+        (http://trustee.ietf.org/license-info).
+
+        This version of this YANG module is part of RFC 8040; see
+        the RFC itself for full legal notices.";
+
+    revision 2017-01-26 {
+	description
+	    "Initial revision.";
+	reference
+	    "RFC 8040: RESTCONF Protocol.";
+    }
+
+    container restconf-state {
+	config false;
+	description
+	    "Contains RESTCONF protocol monitoring information.";
+
+	container capabilities {
+	    description
+		"Contains a list of protocol capability URIs.";
+
+	    leaf-list capability {
+		type inet:uri;
+		description
+		    "A RESTCONF protocol capability URI.";
+	    }
+	}
+
+	container streams {
+	    description
+		"Container representing the notification event streams
+            supported by the server.";
+	    reference
+		"RFC 5277, Section 3.4, <streams> element.";
+
+	    list stream {
+		key name;
+		description
+		    "Each entry describes an event stream supported by
+              the server.";
+
+		leaf name {
+		    type string;
+		    description
+			"The stream name.";
+		    reference
+			"RFC 5277, Section 3.4, <name> element.";
+		}
+
+		leaf description {
+		    type string;
+		    description
+			"Description of stream content.";
+		    reference
+			"RFC 5277, Section 3.4, <description> element.";
+		}
+
+		leaf replay-support {
+		    type boolean;
+		    default false;
+		    description
+			"Indicates if replay buffer is supported for this stream.
+                If 'true', then the server MUST support the 'start-time'
+                and 'stop-time' query parameters for this stream.";
+		    reference
+			"RFC 5277, Section 3.4, <replaySupport> element.";
+		}
+
+		leaf replay-log-creation-time {
+		    when "../replay-support" {
+			description
+			    "Only present if notification replay is supported.";
+		    }
+		    type yang:date-and-time;
+		    description
+			"Indicates the time the replay log for this stream
+                was created.";
+		    reference
+			"RFC 5277, Section 3.4, <replayLogCreationTime>
+                element.";
+		}
+
+		list access {
+		    key encoding;
+		    min-elements 1;
+		    description
+			"The server will create an entry in this list for each
+                encoding format that is supported for this stream.
+                The media type 'text/event-stream' is expected
+                for all event streams.  This list identifies the
+                subtypes supported for this stream.";
+
+		    leaf encoding {
+			type string;
+			description
+			    "This is the secondary encoding format within the
+                  'text/event-stream' encoding used by all streams.
+                  The type 'xml' is supported for XML encoding.
+                  The type 'json' is supported for JSON encoding.";
+		    }
+
+		    leaf location {
+			type inet:uri;
+			mandatory true;
+			description
+			    "Contains a URL that represents the entry point
+                  for establishing notification delivery via
+                  server-sent events.";
+		    }
+		}
+	    }
+	}
+    }
+}