YANG Action (RFC 7950 Section 7.15)

See [Support for "action" statement](https://github.com/clicon/clixon/issues/101)

CHANGELOG.md

@@ -40,6 +40,11 @@ Planned: July 2022
 
 ### New features
 
+* YANG Action (RFC 7950 Section 7.15)
+  * Register action callback with `action_callback_register()`, see main example
+  * Remains: check list keys, validate output
+  * See [Support for "action" statement](https://github.com/clicon/clixon/issues/101)
+
 * TEXT syntax parseable for loading files
   * Previously only supported output
   * TEXT output format changed (see API changes)

apps/backend/backend_client.c

@@ -867,7 +867,6 @@ from_client_kill_session(clicon_handle h,
     return retval;
 }
 
-
 /*! Create a notification subscription
  * @param[in]  h       Clicon handle 
  * @param[in]  xe      Request: <rpc><xn></rpc> 
@@ -1203,7 +1202,6 @@ from_client_hello(clicon_handle       h,
     return retval;
 }
 
-
 /*! An internal clicon message has arrived from a client. Receive and dispatch.
  * @param[in]   h    Clicon handle
  * @param[in]   s    Socket where message arrived. read from this.
@@ -1509,6 +1507,9 @@ backend_rpc_init(clicon_handle h)
     if (rpc_callback_register(h, from_client_kill_session, NULL,
 		      NETCONF_BASE_NAMESPACE, "kill-session") < 0)
 	goto done;
+    if (rpc_callback_register(h, action_callback_call, NULL,
+		      YANG_XML_NAMESPACE, "action") < 0)
+	goto done;
     /* In backend_commit.? */
     if (rpc_callback_register(h, from_client_commit, NULL,
 		      NETCONF_BASE_NAMESPACE, "commit") < 0)

apps/netconf/netconf_rpc.c

@@ -353,8 +353,6 @@ netconf_edit_config(clicon_handle h,
 
 /*! Get running configuration and device state information
  * 
- *
-
  * @param[in]  h       Clicon handle
  * @param[in]  xn      Sub-tree (under xorig) at <rpc>...</rpc> level.
  * @param[out] xret    Return XML, error or OK
@@ -726,7 +724,9 @@ netconf_rpc_dispatch(clicon_handle h,
 	    strcmp(xml_name(xe), "validate") == 0 ||  /* :validate */
 	    strcmp(xml_name(xe), "commit") == 0 || /* :candidate */
 	    strcmp(xml_name(xe), "cancel-commit") == 0 || 
-	    strcmp(xml_name(xe), "discard-changes") == 0){
+	    strcmp(xml_name(xe), "discard-changes") == 0 ||
+	    strcmp(xml_name(xe), "action") == 0
+	    ){
 	    if (clicon_rpc_netconf_xml(h, xml_parent(xe), xret, NULL) < 0)
 		goto done;	
 	}

example/main/example_backend.c

@@ -35,6 +35,7 @@
 
   * The example have the following optional arguments that you can pass as 
   * argc/argv after -- in clixon_backend:
+  *  -a <..> Register callback for this yang action
   *  -r  enable the reset function 
   *  -s  enable the state function
   *  -S <file>  read state data from file, otherwise construct it programmatically (requires -s)
@@ -66,7 +67,14 @@
 #include <clixon/clixon_backend.h> 
 
 /* Command line options to be passed to getopt(3) */
-#define BACKEND_EXAMPLE_OPTS "rsS:x:iuUt:v:"
+#define BACKEND_EXAMPLE_OPTS "a:rsS:x:iuUt:v:"
+
+/*! Yang action
+ * Start backend with -- -a <instance-id>
+ * where instance-id points to an action node in some YANG
+ * Hard-coded to action "reset" from RFC7950 7.15
+ */
+static char *_action_instanceid = NULL;
 
 /*! Variable to control if reset code is run.
  * The reset code inserts "extra XML" which assumes ietf-interfaces is
@@ -357,6 +365,28 @@ example_copy_extra(clicon_handle h,            /* Clicon handle */
     return retval;
 }
 
+/*! Action callback, example from RFC7950 7.15
+ * Note callback is hardcoded C, while registration is controlled by -- -a option
+ */
+static int 
+example_action_reset(clicon_handle h,            /* Clicon handle */
+		     cxobj        *xe,           /* Request: <rpc><xn></rpc> */
+		     cbuf         *cbret,        /* Reply eg <rpc-reply>... */
+		     void         *arg,          /* client_entry */
+		     void         *regarg)       /* Argument given at register */
+{
+    int    retval = -1;
+    char *reset_at;
+
+    if ((reset_at = xml_find_body(xe, "reset-at")) != NULL)
+	/* Just copy input to output */
+	cprintf(cbret, "<rpc-reply xmlns=\"%s\"><reset-finished-at xmlns=\"urn:example:server-farm\">%s</reset-finished-at></rpc-reply>",
+		NETCONF_BASE_NAMESPACE, reset_at);
+    retval = 0;
+    // done:
+    return retval;
+}
+
 /*! Called to get state data from plugin by programmatically adding state
  *
  * @param[in]    h        Clicon handle
@@ -1155,7 +1185,29 @@ example_reset(clicon_handle h,
 int
 example_start(clicon_handle h)
 {
-    return 0;
+    int        retval = -1;
+    yang_stmt *yspec;
+    yang_stmt *ya = NULL;
+
+    /* Register action callback, example from RFC7950 7.15
+     * Can not be made in _init since YANG is not loaded
+     * Note that callback is hardcoded here since it is C, but YANG and name of action
+     * is not. It is enough to point via an schema-node id to the correct action,
+     * such as "/sfarm:server/sfarm:reset"
+     */
+    if (_action_instanceid){
+	if ((yspec = clicon_dbspec_yang(h)) == NULL){
+	    clicon_err(OE_FATAL, 0, "No DB_SPEC");
+	    goto done;
+	}
+	if (yang_abs_schema_nodeid(yspec, _action_instanceid, &ya) == 0){
+	    if (ya && action_callback_register(h, ya, example_action_reset, NULL) < 0)
+		goto done;
+	}
+    }
+    retval = 0;
+ done:
+    return retval;
 }
 
 /*! Plugin daemon.
@@ -1254,6 +1306,9 @@ clixon_plugin_init(clicon_handle h)
     optind = 1;
     while ((c = getopt(argc, argv, BACKEND_EXAMPLE_OPTS)) != -1)
 	switch (c) {
+	case 'a':
+	    _action_instanceid = optarg;
+	    break;
 	case 'r':
 	    _reset = 1;
 	    break;
@@ -1346,6 +1401,7 @@ clixon_plugin_init(clicon_handle h)
 			      "copy-config"
 			      ) < 0)
 	goto done;
+
     /* Upgrade callback: if you start the backend with -- -u you will get the
      * test interface example. Otherwise the auto-upgrade feature is enabled.
      */

include/clixon_custom.h

@@ -163,3 +163,20 @@
  * If not set, client will exit
  */
 #define PROTO_RESTART_RECONNECT
+
+/*! Text output keys as identifiers instead of ordinary leafs
+ * That is, given list "list" with key value "a", if set, the output of show config or save
+ * as text command is:
+ *    list a { 
+ *       val 42; 
+ *    }
+ * If not set, the output is:
+ *    list { 
+ *       keyname a; 
+ *       val 42; 
+ *    }
+ * The TEXT parser (ie load) accepts both formats.
+ */
+#define TEXT_LIST_KEYS
+
+

lib/clixon/clixon_plugin.h

@@ -360,6 +360,26 @@ typedef struct clixon_plugin clixon_plugin_t;
  * The internal struct is defined in clixon_plugin.c */
 typedef struct plugin_context plugin_context_t;
 
+/*
+ * RPC callbacks for both client/frontend and backend plugins.
+ * RPC callbacks are explicitly registered in the plugin_init() function
+ * with a tag and a function
+ * When the the tag is encountered, the callback is called.
+ * Primarily backend, but also netconf and restconf frontend plugins.
+ * CLI frontend so far have direct callbacks, ie functions in the cligen
+ * specification are directly dlsym:ed to the CLI plugin.
+ * It would be possible to use this rpc registering API for CLI plugins as well.
+ * 
+ * When namespace and name match, the callback is made
+ */
+typedef struct {
+    qelem_t       rc_qelem;	/* List header */
+    clicon_rpc_cb rc_callback;  /* RPC Callback */
+    void         *rc_arg;	/* Application specific argument to cb */
+    char         *rc_namespace;/* Namespace to combine with name tag */
+    char         *rc_name;	/* Xml/json tag/name */
+} rpc_callback_t;
+
 /*
  * Prototypes
  */
@@ -402,6 +422,11 @@ int clixon_plugin_datastore_upgrade_all(clicon_handle h, const char *db, cxobj *
 /* rpc callback API */
 int rpc_callback_register(clicon_handle h, clicon_rpc_cb cb, void *arg, const char *ns, const char *name);
 int rpc_callback_call(clicon_handle h, cxobj *xe, void *arg, int *nrp, cbuf *cbret);
+
+/* action callback API */
+int action_callback_register(clicon_handle h, yang_stmt *ya, clicon_rpc_cb cb, void *arg);
+int action_callback_call(clicon_handle h, cxobj *xe, cbuf *cbret, void *arg, void *regarg);
+
 /* upgrade callback API */
 int upgrade_callback_reg_fn(clicon_handle h, clicon_upgrade_cb cb, const char *strfn, const char *ns, void *arg);
 int upgrade_callback_call(clicon_handle h, cxobj *xt, char *ns, uint16_t op, uint32_t from, uint32_t to, cbuf *cbret);

lib/clixon/clixon_xml_map.h

@@ -73,5 +73,7 @@ int xml_merge(cxobj *x0, cxobj *x1, yang_stmt *yspec, char **reason);
 int yang_enum_int_value(cxobj *node, int32_t *val);
 int xml_copy_marked(cxobj *x0, cxobj *x1);
 int yang_check_when_xpath(cxobj *xn, cxobj *xp, yang_stmt *yn, int *hit, int *nrp, char **xpathp);
+int xml_rpc_isaction(cxobj *xn);
+int xml_find_action(cxobj *xn, int top, cxobj **xap);
 
 #endif  /* _CLIXON_XML_MAP_H_ */

lib/clixon/clixon_yang.h

@@ -282,5 +282,7 @@ int        yang_extension_value(yang_stmt *ys, char *name, char *ns, int *exist,
 int        yang_sort_subelements(yang_stmt *ys);
 int        yang_init(clicon_handle h);
 int        yang_single_child_type(yang_stmt *ys, enum rfc_6020 subkeyw);
+void      *yang_action_cb_get(yang_stmt *ys);
+int        yang_action_cb_add(yang_stmt *ys, void *rc);
 
 #endif  /* _CLIXON_YANG_H_ */

lib/src/clixon_plugin.c

@@ -66,7 +66,9 @@
 #include "clixon_options.h"
 #include "clixon_xml.h"
 #include "clixon_xml_nsctx.h"
+#include "clixon_xml_map.h"
 #include "clixon_yang_module.h"
+#include "clixon_netconf_lib.h"
 #include "clixon_validate.h"
 #include "clixon_plugin.h"
 
@@ -94,26 +96,6 @@ struct clixon_plugin{
     clixon_plugin_api cp_api;
 };
 
-/*
- * RPC callbacks for both client/frontend and backend plugins.
- * RPC callbacks are explicitly registered in the plugin_init() function
- * with a tag and a function
- * When the the tag is encountered, the callback is called.
- * Primarily backend, but also netconf and restconf frontend plugins.
- * CLI frontend so far have direct callbacks, ie functions in the cligen
- * specification are directly dlsym:ed to the CLI plugin.
- * It would be possible to use this rpc registering API for CLI plugins as well.
- * 
- * When namespace and name match, the callback is made
- */
-typedef struct {
-    qelem_t       rc_qelem;	/* List header */
-    clicon_rpc_cb rc_callback;  /* RPC Callback */
-    void         *rc_arg;	/* Application specific argument to cb */
-    char         *rc_namespace;/* Namespace to combine with name tag */
-    char         *rc_name;	/* Xml/json tag/name */
-} rpc_callback_t;
-
 /*
  * Upgrade callbacks for backend upgrade of datastore
  * Register upgrade callbacks in plugin_init() with a module and a "from" and "to"
@@ -138,7 +120,6 @@ struct plugin_module_struct {
 };
 typedef struct plugin_module_struct plugin_module_struct;
 
-
 /*! Get plugin handle containing plugin and callback lists
  * @param[in]  h     Clicon handle
  */
@@ -1043,7 +1024,7 @@ rpc_callback_dump(clicon_handle h)
 }
 #endif
 
-/*! Register a RPC callback by appending a new RPC to the list
+/*! Register a RPC callback by appending a new RPC to a global list
  *
  * @param[in]  h         clicon handle
  * @param[in]  cb        Callback called 
@@ -1122,9 +1103,9 @@ rpc_callback_delete_all(clicon_handle h)
  * @param[in]   arg     Domain-speific arg (eg client_entry)
  * @param[out]  nrp     Number of callbacks handled: 0, 1, n (retval = 1) or NULL
  * @param[out]  cbret   Return XML (as string in CLIgen buffer), error or OK
- * @retval -1   Error
+ * @retval      1       OK, see nr
- * @retval  0   Failed, error return in cbret
+ * @retval      0       Failed, error return in cbret
- * @retval  1   OK, see nr
+ * @retval     -1       Error
  * @see rpc_callback_register  which register a callback function
  * @note that several callbacks can be registered. They need to cooperate on
  * return values, ie if one writes cbret, the other needs to handle that by
@@ -1137,14 +1118,14 @@ rpc_callback_call(clicon_handle h,
 		  int          *nrp,
 		  cbuf         *cbret)
 {
-    int            retval = -1;
+    int                   retval = -1;
     rpc_callback_t       *rc;
     char                 *name;
     char                 *prefix;
     char                 *ns;
     int                   nr = 0; /* How many callbacks */
     plugin_module_struct *ms = plugin_module_struct_get(h);
-    void                 *wh = NULL;
+    void                 *wh;
     int                   ret;
 
     if (ms == NULL){
@@ -1174,7 +1155,8 @@ rpc_callback_call(clicon_handle h,
 	    }
 	    rc = NEXTQ(rpc_callback_t *, rc);
 	} while (rc != ms->ms_rpc_callbacks);
-    if (nr){
+    /* action reply checked in action_callback_call */
+    if (nr && !xml_rpc_isaction(xe)){
 	if ((ret = rpc_reply_check(h, name, cbret)) < 0)
 	    goto done;
 	if (ret == 0)
@@ -1191,6 +1173,129 @@ rpc_callback_call(clicon_handle h,
     goto done;
 }
 
+/*--------------------------------------------------------------------
+ * Action callback API. Reuse many of the same data structures as RPC, but
+ * context is given by a yang node
+ */
+
+/*! Register a RPC action callback by appending a new RPC to a yang action node
+ * @param[in]  h     clicon handle
+ * @param[in]  ys    YANG node where action resides
+ * @param[in]  cb    Callback
+ * @param[in]  arg   Domain-specific argument to send to callback 
+ * @retval     0     OK
+ * @retval    -1     Error
+ * @see rpc_callback_register  which registers global callbacks
+ */
+int
+action_callback_register(clicon_handle  h,
+			 yang_stmt     *ya,
+			 clicon_rpc_cb  cb,
+			 void          *arg)
+{
+    int             retval = -1;
+    rpc_callback_t *rc = NULL;
+    char           *name;
+
+    clicon_debug(1, "%s", __FUNCTION__);
+    if (ya == NULL){
+	clicon_err(OE_DB, EINVAL, "yang node is NULL");
+	goto done;
+    }
+    name = yang_argument_get(ya);
+    if ((rc = malloc(sizeof(rpc_callback_t))) == NULL) {
+	clicon_err(OE_DB, errno, "malloc");
+	goto done;
+    }
+    memset(rc, 0, sizeof(*rc));
+    rc->rc_callback = cb;
+    rc->rc_arg  = arg;
+    rc->rc_namespace  = strdup(YANG_XML_NAMESPACE); // XXX
+    rc->rc_name  = strdup(name);
+    if (yang_action_cb_add(ya, rc) < 0)
+	goto done;
+    retval = 0;
+ done:
+    return retval;
+}
+
+/*! Search Action callbacks and invoke if XML match with tag
+ *
+ * @param[in]   h       clicon handle
+ * @param[in]   xn      Sub-tree (under xorig) at child of rpc: <rpc><xn></rpc>.
+ * @param[in]   arg     Domain-speific arg (eg client_entry)
+ * @param[out]  nrp     Number of callbacks handled: 0, 1, n (retval = 1) or NULL
+ * @param[out]  cbret   Return XML (as string in CLIgen buffer), error or OK
+ * @retval      1       OK, see nr
+ * @retval      0       Failed, error return in cbret
+ * @retval     -1       Error
+ * @see rpc_callback_register  which register a callback function
+ * @note that several callbacks can be registered. They need to cooperate on
+ * return values, ie if one writes cbret, the other needs to handle that by
+ * leaving it, replacing it or amending it.
+ */
+int
+action_callback_call(clicon_handle h,
+		     cxobj        *xe, 
+		     cbuf         *cbret,
+		     void         *arg,
+		     void         *regarg)
+{
+    int             retval = -1;
+    cxobj          *xa = NULL;
+    yang_stmt      *ya = NULL;
+    char           *name;
+    int             nr = 0; /* How many callbacks */
+    void           *wh = NULL;
+    rpc_callback_t *rc;
+    
+    clicon_debug(1, "%s", __FUNCTION__);
+    if (xml_find_action(xe, 1, &xa) < 0)
+	goto done;
+    if (xa == NULL){
+	if (netconf_operation_not_supported(cbret, "application", "Action not found") < 0)
+	    goto done;
+	goto ok;		
+    }
+    if ((ya = xml_spec(xa)) == NULL){
+	if (netconf_operation_not_supported(cbret, "application", "Action spec not found") < 0)
+	    goto done;
+	goto ok;		
+    }
+    name = xml_name(xa);
+    /* Action callback */
+    if ((rc = (rpc_callback_t *)yang_action_cb_get(ya)) != NULL){
+	do {
+	    if (strcmp(rc->rc_name, name) == 0){
+		if (plugin_context_check(h, &wh, rc->rc_name, __FUNCTION__) < 0)
+		    goto done;
+		if (rc->rc_callback(h, xa, cbret, arg, rc->rc_arg) < 0){
+		    clicon_debug(1, "%s Error in: %s", __FUNCTION__, rc->rc_name);
+		    if (plugin_context_check(h, &wh, rc->rc_name, __FUNCTION__) < 0)
+			goto done;
+		    goto done;
+		}
+		nr++;
+		if (plugin_context_check(h, &wh, rc->rc_name, __FUNCTION__) < 0)
+		    goto done;
+	    }
+	    rc = NEXTQ(rpc_callback_t *, rc);
+	} while (rc != yang_action_cb_get(ya));
+    }
+    if (nr){
+#ifdef NYI
+	if ((ret = rpc_action_reply_check(h, xe, cbret)) < 0)
+	    goto done;
+	if (ret == 0)
+	    goto fail;
+#endif
+    }
+ ok:
+    retval = 1;
+ done:
+    return retval;
+}
+
 /*--------------------------------------------------------------------
  * Upgrade callbacks for backend upgrade of datastore
  */

lib/src/clixon_validate.c

@@ -371,7 +371,6 @@ xml_yang_validate_rpc(clicon_handle h,
 		      cxobj       **xret)
 {
     int        retval = -1;
-    yang_stmt *yn=NULL;  /* rpc name */
     cxobj     *xn;       /* rpc name */
     char      *rpcprefix;
     char      *namespace = NULL;
@@ -393,7 +392,7 @@ xml_yang_validate_rpc(clicon_handle h,
     xn = NULL;
     /* xn is name of rpc, ie <rcp><xn/></rpc> */
     while ((xn = xml_child_each(xrpc, xn, CX_ELMNT)) != NULL) {
-	if ((yn = xml_spec(xn)) == NULL){
+	if (xml_spec(xn) == NULL){
 	    if (xret && netconf_unknown_element_xml(xret, "application", xml_name(xn), NULL) < 0)
 		goto done;
 	    goto fail;

lib/src/clixon_xml_bind.c

@@ -77,6 +77,7 @@
 #include "clixon_netconf_lib.h"
 #include "clixon_xml_sort.h"
 #include "clixon_yang_type.h"
+#include "clixon_xml_map.h"
 #include "clixon_xml_bind.h"
 
 /*
@@ -183,31 +184,33 @@ populate_self_parent(cxobj  *xt,
     }
     if (xml2ns(xt, xml_prefix(xt), &ns) < 0)
 	goto done;
-    if ((y = yang_find_datanode(yparent, name)) == NULL){
+    /* Special case since action is not a datanode */
-	if (_yang_unknown_anydata){
+    if ((y = yang_find(yparent, Y_ACTION, name)) == NULL)
-	    /* Add dummy Y_ANYDATA yang stmt, see ysp_add */
+	if ((y = yang_find_datanode(yparent, name)) == NULL){
-	    if ((y = yang_anydata_add(yparent, name)) < 0)
+	    if (_yang_unknown_anydata){
+		/* Add dummy Y_ANYDATA yang stmt, see ysp_add */
+		if ((y = yang_anydata_add(yparent, name)) < 0)
+		    goto done;
+		xml_spec_set(xt, y);
+		retval = 2; /* treat as anydata */
+		clicon_log(LOG_WARNING,
+			   "%s: %d: No YANG spec for %s, anydata used",
+			   __FUNCTION__, __LINE__, name);
 		goto done;
-	    xml_spec_set(xt, y);
+	    }
-	    retval = 2; /* treat as anydata */
+	    if ((cb = cbuf_new()) == NULL){
-	    clicon_log(LOG_WARNING,
+		clicon_err(OE_UNIX, errno, "cbuf_new");
-		       "%s: %d: No YANG spec for %s, anydata used",
+		goto done;
-		       __FUNCTION__, __LINE__, name);
+	    }
-	    goto done;
+	    cprintf(cb, "Failed to find YANG spec of XML node: %s", name);
+	    cprintf(cb, " with parent: %s", xml_name(xp));
+	    if (ns)
+		cprintf(cb, " in namespace: %s", ns);
+	    if (xerr &&
+		netconf_unknown_element_xml(xerr, "application", name, cbuf_get(cb)) < 0)
+		goto done;
+	    goto fail;
 	}
-	if ((cb = cbuf_new()) == NULL){
-	    clicon_err(OE_UNIX, errno, "cbuf_new");
-	    goto done;
-	}
-	cprintf(cb, "Failed to find YANG spec of XML node: %s", name);
-	cprintf(cb, " with parent: %s", xml_name(xp));
-	if (ns)
-	    cprintf(cb, " in namespace: %s", ns);
-	if (xerr &&
-	    netconf_unknown_element_xml(xerr, "application", name, cbuf_get(cb)) < 0)
-	    goto done;
-	goto fail;
-    }
     nsy = yang_find_mynamespace(y);
     if (ns == NULL || nsy == NULL){
 	if (xerr &&
@@ -516,6 +519,92 @@ xml_bind_yang0(cxobj     *xt,
     goto done;
 }
 
+/*! RPC-specific
+ */
+static int
+xml_bind_yang_rpc_rpc(cxobj     *x,
+		      yang_stmt *yrpc,
+		      char      *rpcname,
+		      cxobj    **xerr)
+{
+    int        retval = -1;
+    cbuf      *cb = NULL;
+    char      *name;
+    cxobj     *xc;
+    yang_stmt *yi = NULL; /* input */
+    int        ret;
+
+    xml_spec_set(x, yrpc); /* required for validate */
+    if ((yi = yang_find(yrpc, Y_INPUT, NULL)) == NULL){
+	/* If no yang input spec but RPC has elements, return unknown element */
+	if (xml_child_nr_type(x, CX_ELMNT) != 0){
+	    xc = xml_child_i_type(x, 0, CX_ELMNT); /* Pick first */
+	    name = xml_name(xc);
+	    if ((cb = cbuf_new()) == NULL){
+		clicon_err(OE_UNIX, errno, "cbuf_new");
+		goto done;
+	    }
+	    cprintf(cb, "Unrecognized parameter: %s in rpc: %s", name, rpcname);
+	    if (xerr &&
+		netconf_unknown_element_xml(xerr, "application", name, cbuf_get(cb)) < 0)
+		goto done;
+	    goto fail;
+	}
+    }
+    else{
+	/* xml_bind_yang need to have parent with yang spec for
+	 * recursive population to work. Therefore, assign input yang
+	 * to rpc level although not 100% intuitive */
+	xml_spec_set(x, yi); 
+	if ((ret = xml_bind_yang(x, YB_PARENT, NULL, xerr)) < 0)
+	    goto done;
+	if (ret == 0)
+	    goto fail;
+    }
+    retval = 1;
+ done:
+    if (cb)
+	cbuf_free(cb);
+    return retval;
+ fail:
+    retval = 0;
+    goto done;
+}
+
+/*! Action-specific
+ *
+ * Find the innermost container or list containing an XML element that carries the name of the
+ * defined action.
+ * Only one action can be invoked in one rpc
+ * XXX if not more action, consider folding into calling function
+ */
+static int
+xml_bind_yang_rpc_action(cxobj     *xn,
+			 yang_stmt *yspec,
+			 cxobj    **xerr)
+{
+    int        retval = -1;
+    int        ret;
+    cxobj     *xi;
+    yang_stmt *yi;;
+
+    if ((ret = xml_bind_yang(xn, YB_MODULE, yspec, xerr)) < 0)
+	goto done;
+    if (ret == 0)
+	goto fail;
+    /* Special case: bind "action" node to module for validate code to work */
+    if ((xi = xml_child_i_type(xn, 0, CX_ELMNT)) != NULL &&
+	(yi = xml_spec(xi))){
+	xml_spec_set(xn, ys_module(yi));
+    }
+    retval = 1;
+ done:
+    return retval;
+ fail:
+    retval = 0;
+    goto done;
+}
+
 /*! Find yang spec association of XML node for incoming RPC starting with <rpc>
  * 
  * Incoming RPC has an "input" structure that is not taken care of by xml_bind_yang
@@ -541,13 +630,11 @@ xml_bind_yang_rpc(cxobj        *xrpc,
     int        retval = -1;
     yang_stmt *yrpc = NULL;    /* yang node */
     yang_stmt *ymod=NULL; /* yang module */
-    yang_stmt *yi = NULL; /* input */
     cxobj     *x;
     int        ret;
     char      *opname;  /* top-level netconf operation */
     char      *rpcname; /* RPC name */
     char      *name;
-    cbuf      *cb = NULL;
     cxobj     *xc;
     
     opname = xml_name(xrpc);
@@ -607,6 +694,15 @@ xml_bind_yang_rpc(cxobj        *xrpc,
     x = NULL;
     while ((x = xml_child_each(xrpc, x, CX_ELMNT)) != NULL) {
 	rpcname = xml_name(x);
+	if ((ret = xml_rpc_isaction(x)) < 0)
+	    goto done;
+	if (ret == 1){
+	    if ((ret = xml_bind_yang_rpc_action(x, yspec, xerr)) < 0)
+		goto done;
+	    if (ret == 0)
+		goto fail;
+	    goto ok;
+	} /* if not action fall through */
 	if (ys_module_by_xml(yspec, x, &ymod) < 0)
 	    goto done;
 	if (ymod == NULL){
@@ -621,39 +717,14 @@ xml_bind_yang_rpc(cxobj        *xrpc,
 		goto done;
 	    goto fail;
 	}
-	xml_spec_set(x, yrpc); /* required for validate */
+	if ((ret = xml_bind_yang_rpc_rpc(x, yrpc, rpcname, xerr)) < 0)
-	if ((yi = yang_find(yrpc, Y_INPUT, NULL)) == NULL){
+	    goto done;
-	    /* If no yang input spec but RPC has elements, return unknown element */
+	if (ret == 0)
-	    if (xml_child_nr_type(x, CX_ELMNT) != 0){
+	    goto fail;
-		xc = xml_child_i_type(x, 0, CX_ELMNT); /* Pick first */
-		name = xml_name(xc);
-		if ((cb = cbuf_new()) == NULL){
-		    clicon_err(OE_UNIX, errno, "cbuf_new");
-		    goto done;
-		}
-		cprintf(cb, "Unrecognized parameter: %s in rpc: %s", name, rpcname);
-		if (xerr &&
-		    netconf_unknown_element_xml(xerr, "application", name, cbuf_get(cb)) < 0)
-		    goto done;
-		goto fail;
-	    }
-	}
-	else{
-	    /* xml_bind_yang need to have parent with yang spec for
-	     * recursive population to work. Therefore, assign input yang
-	     * to rpc level although not 100% intuitive */
-	    xml_spec_set(x, yi); 
-	    if ((ret = xml_bind_yang(x, YB_PARENT, NULL, xerr)) < 0)
-		goto done;
-	    if (ret == 0)
-		goto fail;
-	}
     }
  ok:
     retval = 1;
  done:
-    if (cb)
-	cbuf_free(cb);
     return retval;
  fail:
     retval = 0;

lib/src/clixon_xml_map.c

@@ -2025,3 +2025,66 @@ yang_check_when_xpath(cxobj        *xn,
     return retval;
 }
 
+/*! Is XML node (ie under <rpc>) an action, ie name action and belong to YANG_XML_NAMESPACE?
+ * @param[in]   xn   XML node
+ * @retval      1    Yes, an action
+ * @retval      0    No, not an action
+ * @retval     -1    Error
+ */
+int
+xml_rpc_isaction(cxobj *xn)
+{
+    int   retval = -1;
+    char *ns = NULL;
+
+    if (strcmp(xml_name(xn), "action") != 0)
+	goto fail;
+    if (xml2ns(xn, xml_prefix(xn), &ns) < 0)
+	goto done;
+    if (strcmp(YANG_XML_NAMESPACE, ns) != 0)
+	goto fail;
+    retval = 1; // is action
+ done:
+    return retval;
+ fail:
+    retval = 0;
+    goto done;
+}
+
+/*! Find innermost node under <action> carrying the name of the defined action
+ *  Find innermost container or list contains an XML element
+ *  that carries the name of the defined action. 
+ * @param[in]   xn   XML node
+ * @param[in]   top  If set, dont look for action node since top-level
+ * @param[out]  xap  Pointer to xml action node
+ * @retval      0    OK
+ * @retval     -1    Error
+ * XXX: does not look at list key
+ */
+int
+xml_find_action(cxobj  *xn,
+		int     top,
+		cxobj **xap)
+{
+    int        retval = -1;
+    cxobj     *xc = NULL;
+    yang_stmt *yc;
+
+    while ((xc = xml_child_each(xn, xc, CX_ELMNT)) != NULL) {
+	if ((yc = xml_spec(xc)) == NULL)
+	    continue;
+	if (!top && yang_keyword_get(yc) == Y_ACTION){
+	    *xap = xc;
+	    break;
+	}
+	if (yang_keyword_get(yc) != Y_CONTAINER && yang_keyword_get(yc) != Y_LIST)
+	    continue;
+	/* XXX check key */
+	if (xml_find_action(xc, 0, xap) < 0)
+	    goto done;
+	break;
+    }
+    retval = 0;
+ done:
+    return retval;
+}

lib/src/clixon_yang.c

@@ -625,7 +625,8 @@ int
 ys_free1(yang_stmt *ys,
 	 int        self)
 {
-    cg_var *cv;
+    cg_var         *cv;
+    rpc_callback_t *rc;
 
     if (ys->ys_argument){
 	free(ys->ys_argument);
@@ -651,6 +652,14 @@ ys_free1(yang_stmt *ys,
 	free(ys->ys_stmt);
     if (ys->ys_filename)
 	free(ys->ys_filename);
+    while((rc = ys->ys_action_cb) != NULL) {
+	DELQ(rc, ys->ys_action_cb, rpc_callback_t *);
+	if (rc->rc_namespace)
+	    free(rc->rc_namespace);
+	if (rc->rc_name)
+	    free(rc->rc_name);
+	free(rc);
+    }
     if (self){
 	free(ys);
 	_stats_yang_nr--;
@@ -1106,19 +1115,22 @@ yang_find_datanode(yang_stmt *yn,
 				ysmatch = yc;
 		    }
 		if (ysmatch)
-		    goto match;
+		    goto match; // maybe break?
 	    }
 	} /* Y_CHOICE */
-	else{
+	else if (yang_keyword_get(ys) == Y_INPUT ||
-	    if (yang_datanode(ys)){
+		 yang_keyword_get(ys) == Y_OUTPUT){ /* Look for its children */
-		if (argument == NULL)
+	    if ((ysmatch = yang_find_datanode(ys, argument)) != NULL)
+		break;
+	}
+	else if (yang_datanode(ys)){
+	    if (argument == NULL)
+		ysmatch = ys;
+	    else
+		if (ys->ys_argument && strcmp(argument, ys->ys_argument) == 0)
 		    ysmatch = ys;
-		else
+	    if (ysmatch)
-		    if (ys->ys_argument && strcmp(argument, ys->ys_argument) == 0)
+		goto match; // maybe break?
-			ysmatch = ys;
-		if (ysmatch)
-		    goto match;
-	    }
 	}
     }
     /* Special case: if not match and yang node is module or submodule, extend
@@ -1146,6 +1158,7 @@ yang_find_datanode(yang_stmt *yn,
  * @param[in]  argument   if NULL, match any(first) argument.
  * @note XXX unify code with yang_find_datanode?
  * @see yang_find_datanode
+ * @see yang_abs_schema_nodeid  Top level function
  */
 yang_stmt *
 yang_find_schemanode(yang_stmt *yn, 
@@ -3994,3 +4007,28 @@ yang_single_child_type(yang_stmt    *ys,
     return 1; /* Passed all tests: yes you can hide this keyword */
 }
 
+/*! Get action callback list
+ * XXX rc shouldnt really be void* but the type definitions in .h file got complicated
+ */
+void *
+yang_action_cb_get(yang_stmt *ys)
+{
+    return ys->ys_action_cb;
+}
+
+/*! Add an action callback to YANG node
+ * XXX rc shouldnt really be void* but the type definitions in .h file got complicated
+ */
+int
+yang_action_cb_add(yang_stmt *ys,
+		   void      *arg)
+{
+    rpc_callback_t *rc = (rpc_callback_t *)arg;
+
+    if (rc == NULL){
+	clicon_err(OE_YANG, EINVAL, "arg is NULL");
+	return -1;
+    }    
+    ADDQ(rc, ys->ys_action_cb);
+    return 0;
+}

lib/src/clixon_yang_internal.h

@@ -101,10 +101,10 @@ struct yang_stmt{
     cvec              *ys_when_nsc;   /* Special conditional for a "when"-associated augment/uses namespace ctx */
     char              *ys_filename;   /* For debug/errors: filename (only (sub)modules) */
     int                ys_linenum;    /* For debug/errors: line number (in ys_filename) */
+    rpc_callback_t    *ys_action_cb;  /* Action callback list, only for Y_ACTION */
     /* Internal use */
     int               _ys_vector_i;   /* internal use: yn_each */
 };
 
-
 #endif  /* _CLIXON_YANG_INTERNAL_H_ */
 

lib/src/clixon_yang_parse_lib.c

@@ -85,7 +85,6 @@
 #include "clixon_handle.h"
 #include "clixon_file.h"
 #include "clixon_yang.h"
-#include "clixon_yang_internal.h"
 #include "clixon_hash.h"
 #include "clixon_xml.h"
 #include "clixon_xml_nsctx.h"
@@ -98,6 +97,8 @@
 #include "clixon_yang_type.h"
 #include "clixon_yang_parse.h"
 #include "clixon_yang_cardinality.h"
+#include "clixon_plugin.h"
+#include "clixon_yang_internal.h"
 #include "clixon_yang_parse_lib.h"
 
 /* Size of json read buffer when reading from file*/

test/test_yang_action.sh

@@ -0,0 +1,94 @@
+#!/usr/bin/env bash
+# Yang action, use main exapl backend for registering action
+# See RFC 7950 7.15
+
+# Magic line must be first in script (see README.md)
+s="$_" ; . ./lib.sh || if [ "$s" = "$0" ]; then exit 0; else return 0; fi
+
+APPNAME=example
+
+cfg=$dir/conf_yang.xml
+fyang=$dir/example-server-farm.yang
+
+cat <<EOF > $cfg
+<clixon-config xmlns="http://clicon.org/config">
+  <CLICON_CONFIGFILE>$cfg</CLICON_CONFIGFILE>
+  <CLICON_YANG_DIR>${YANG_INSTALLDIR}</CLICON_YANG_DIR>
+  <CLICON_YANG_DIR>$dir</CLICON_YANG_DIR>
+  <CLICON_YANG_MAIN_DIR>$dir</CLICON_YANG_MAIN_DIR>
+  <CLICON_CLISPEC_DIR>/usr/local/lib/$APPNAME/clispec</CLICON_CLISPEC_DIR>
+  <CLICON_CLI_DIR>/usr/local/lib/$APPNAME/cli</CLICON_CLI_DIR>
+  <CLICON_CLI_MODE>$APPNAME</CLICON_CLI_MODE>
+  <CLICON_SOCK>/usr/local/var/$APPNAME/$APPNAME.sock</CLICON_SOCK>
+  <CLICON_BACKEND_DIR>/usr/local/lib/$APPNAME/backend</CLICON_BACKEND_DIR>
+  <CLICON_BACKEND_PIDFILE>/usr/local/var/$APPNAME/$APPNAME.pidfile</CLICON_BACKEND_PIDFILE>
+  <CLICON_XMLDB_DIR>/usr/local/var/$APPNAME</CLICON_XMLDB_DIR>
+</clixon-config>
+EOF
+
+cat <<EOF > $fyang
+  module example-server-farm {
+       yang-version 1.1;
+       namespace "urn:example:server-farm";
+       prefix "sfarm";
+
+       import ietf-yang-types {
+         prefix "yang";
+       }
+
+       list server {
+         key name;
+         leaf name {
+           type string;
+         }
+         action reset {
+           input {
+             leaf reset-at {
+               type yang:date-and-time;
+               mandatory true;
+              }
+            }
+            output {
+              leaf reset-finished-at {
+                type yang:date-and-time;
+                mandatory true;
+              }
+            }
+          }
+        }
+      }
+EOF
+
+if [ $BE -ne 0 ]; then     # Bring your own backend
+    new "kill old backend"
+    sudo clixon_backend -zf $cfg
+    if [ $? -ne 0 ]; then
+	err
+    fi
+    new "start backend -s init -f $cfg -- -a /sfarm:server/sfarm:reset"
+    start_backend -s init -f $cfg -- -a /sfarm:server/sfarm:reset
+fi
+
+new "wait backend"
+wait_backend
+
+rpc="<rpc $DEFAULTNS><action xmlns=\"urn:ietf:params:xml:ns:yang:1\"><server xmlns=\"urn:example:server-farm\"><name>apache-1</name><reset><reset-at>2014-07-29T13:42:00Z</reset-at></reset></server></action></rpc>"
+       
+new "netconf action"
+expecteof_netconf "$clixon_netconf -qf $cfg" 0 "$DEFAULTHELLO" "$rpc" "" "<rpc-reply $DEFAULTNS><reset-finished-at xmlns=\"urn:example:server-farm\">2014-07-29T13:42:00Z</reset-finished-at></rpc-reply>"
+
+if [ $BE -ne 0 ]; then     # Bring your own backend
+    new "Kill backend"
+    # Check if premature kill
+    pid=$(pgrep -u root -f clixon_backend)
+    if [ -z "$pid" ]; then
+	err "backend already dead"
+    fi
+    # kill backend
+    stop_backend -f $cfg
+fi
+
+rm -rf "$dir"
+
+new "endtest"
+endtest