* Clixon transaction mechanism has changed which may affect your backend plugin callbacks:

* Validate-only transactions are terminated by an `end` or `abort` callback.
* If a commit user callback fails, a new `revert` callback will be made to plugins that have made a succesful commit.

CHANGELOG.md

@@ -53,6 +53,11 @@
 	
 ### API changes on existing features (you may need to change your code)
 
+* Clixon transaction mechanism has changed which may affect your backend plugin callbacks:
+  * Validate-only transactions are terminated by an `end` or `abort` callback. Now all started transactions are terminated either by an `end` or `abort` without exceptions
+    * Validate-only transactions used to be terminated by `complete`
+  * If a commit user callback fails, a new `revert` callback will be made to plugins that have made a succesful commit. 
+    * Clixon used to play the (already made) commit callbacks in reverse order
 * Clixon config option `CLICON_XMLDB_CACHE` renamed to `CLICON_DATASTORE_CACHE` and changed type from `boolean` to `datastore_cache`
   * Change code from: `clicon_option_bool(h, "CLICON_XMLDB_CACHE")` to `clicon_datastore_cache(h) == DATASTORE_CACHE`
   * Type `datastore_cache` have values: nocache, cache, or cache-zerocopy

apps/backend/backend_commit.c

@@ -271,10 +271,15 @@ startup_validate(clicon_handle  h,
     /* Handcraft a transition with only target and add trees */
     if ((td = transaction_new()) == NULL)
 	goto done;
-    if ((ret = startup_common(h, db, td, cbret)) < 0)
+    if ((ret = startup_common(h, db, td, cbret)) < 0){
+	plugin_transaction_abort(h, td);
 	goto done;
-    if (ret == 0)
+    }
+    if (ret == 0){
+	plugin_transaction_abort(h, td);
 	goto fail;
+    }
+    plugin_transaction_end(h, td);
      /* Clear cached trees from default values and marking */
     if (xmldb_get_clear(h, td->td_target) < 0)
 	 goto done;
@@ -348,10 +353,11 @@ startup_commit(clicon_handle  h,
 	 goto fail;
     /* 10. Call plugin transaction end callbacks */
     plugin_transaction_end(h, td);
-
     retval = 1;
  done:
     if (td){
+	if (retval < 1)
+	    plugin_transaction_abort(h, td);
 	 xmldb_get_free(h, &td->td_target);
 	 transaction_free(td);
     }
@@ -548,9 +554,9 @@ candidate_commit(clicon_handle h,
     retval = 1;
  done:
      /* In case of failure (or error), call plugin transaction termination callbacks */
-     if (retval < 1 && td)
-	 plugin_transaction_abort(h, td);
      if (td){
+	 if (retval < 1)
+	     plugin_transaction_abort(h, td);
 	 xmldb_get_free(h, &td->td_target);
 	 xmldb_get_free(h, &td->td_src);
 	 transaction_free(td);
@@ -730,33 +736,37 @@ from_client_validate(clicon_handle h,
 	goto done;
     /* Common steps (with commit) */
     if ((ret = from_validate_common(h, db, td, cbret)) < 1){
-	clicon_debug(1, "Validate %s failed",  db);
+	plugin_transaction_abort(h, td);
-	if (ret < 0){
 	if (netconf_operation_failed(cbret, "application", clicon_err_reason)< 0)
 	    goto done;
-	}
 	goto ok;
     }
     /* Clear cached trees from default values and marking */
     if (xmldb_get_clear(h, td->td_target) < 0)
 	goto done;
-    if (xmldb_get_clear(h, td->td_src) < 0)
+    if (xmldb_get_clear(h, td->td_src) < 0 ||
+	xmldb_get_clear(h, td->td_target) < 0){
+	plugin_transaction_abort(h, td);
 	goto done;
+    }
 
     /* Optionally write (potentially modified) tree back to candidate */
     if (clicon_option_bool(h, "CLICON_TRANSACTION_MOD")){
+	plugin_transaction_abort(h, td);
 	if ((ret = xmldb_put(h, "candidate", OP_REPLACE, td->td_target,
 			     clicon_username_get(h), cbret)) < 0)
 	    goto done;
 	goto ok;
     }
     cprintf(cbret, "<rpc-reply><ok/></rpc-reply>");
+    /* Call plugin transaction end callbacks */
+    plugin_transaction_end(h, td);
  ok:
     retval = 0;
  done:
-    if (retval < 0 && td)
-	plugin_transaction_abort(h, td);
     if (td){
+	if (retval < 0)
+	    plugin_transaction_abort(h, td);
 	 xmldb_get_free(h, &td->td_target);
 	 xmldb_get_free(h, &td->td_src);
 	 transaction_free(td);

apps/backend/backend_plugin.c

@@ -295,28 +295,14 @@ plugin_transaction_revert(clicon_handle       h,
 			  int                 nr)
 {
     int                retval = 0;
-    transaction_data_t tr; /* revert transaction */
     clixon_plugin     *cp = NULL;
     trans_cb_t        *fn;
     
-    /* Create a new reversed transaction from the original where src and target
-       are swapped */
-    memcpy(&tr, td, sizeof(tr));
-    tr.td_src   = td->td_target;
-    tr.td_target = td->td_src;
-    tr.td_dlen  = td->td_alen;
-    tr.td_dvec  = td->td_avec;
-    tr.td_alen  = td->td_dlen;
-    tr.td_avec  = td->td_dvec;
-    tr.td_clen  = td->td_clen;
-    tr.td_scvec = td->td_tcvec;
-    tr.td_tcvec = td->td_scvec;
-
     while ((cp = clixon_plugin_each_revert(h, cp, nr)) != NULL) {
-	if ((fn = cp->cp_api.ca_trans_commit) == NULL)
+	if ((fn = cp->cp_api.ca_trans_revert) == NULL)
 	    continue;
-	if ((retval = fn(h, (transaction_data)&tr)) < 0){
+	if ((retval = fn(h, (transaction_data)td)) < 0){
-		clicon_log(LOG_NOTICE, "%s: Plugin '%s' trans_commit revert callback failed", 
+		clicon_log(LOG_NOTICE, "%s: Plugin '%s' trans_revert callback failed", 
 			   __FUNCTION__, cp->cp_name);
 		break; 
 	}

doc/FAQ.md

@@ -15,7 +15,8 @@
   * [How do I use restconf?](#how-do-i-use-restconf)
   * [What about reference documentation?](#what-about-reference-documentation)
   * [How is configuration data stored?](#how-is-configuration-data-stored)
-  * [What is validate and commit?](#what-is-validate-and-commit)
+  * [What is validate and commit?](#what-is-validate-and-commi)t
+  * [Does Clixon support transactions?](#does-clixon-support-transactions)
   * [What is a Clixon configuration file?](#what-is-a-clixon-configuration-file)
   * [How are Clixon configuration files found?](#how-are-clixon-configuration-files-found)
   * [Can I modify clixon options at runtime?](#can-i-modify-clixon-options-at-runtime)
@@ -227,6 +228,42 @@ A clixon developer writes commit functions to incrementaly upgrade a
 system state based on configuration changes. Writing commit callbacks
 is the core functionality of a clixon system.
 
+## Does Clixon support transactions?
+
+Yes. The netconf validation and commit operation is implemented in
+Clixon by a transaction mechanism, which ensures that user-written
+plugin callbacks are invoked atomically and revert on error.  If you
+have two plugins, for example, a transaction sequence looks like the
+following:
+```
+Backend   Plugin1    Plugin2
+  |          |          |
+  +--------->+--------->+ begin
+  |          |          |
+  +--------->+--------->+ validate
+  |          |          |
+  +--------->+--------->+ commit
+  |          |          |
+  +--------->+--------->+ end
+```
+
+If an error occurs in the commit call of Plugin2, for example,
+the transaction is aborted and the commit reverted:
+```
+Backend   Plugin1    Plugin2
+  |          |          |
+  +--------->+--------->+ begin
+  |          |          |
+  +--------->+--------->+ validate
+  |          |          |
+  +--------->+---->X    + commit error
+  |          |          |
+  +--------->+          + revert
+  |          |          |
+  +--------->+--------->+ abort
+```
+
+
 ## What is a Clixon configuration file?
 
 Clixon options are stored in an XML configuration file. The default
@@ -430,7 +467,6 @@ Each plugin is initiated with an API struct followed by a plugin init function a
 ```
 For more info see [../example/main/README.md]
 
-
 ## How do I write a commit function?
 In the example, you write a commit function in example_backend.c.
 Every time a commit is made, transaction_commit() is called in the

example/main/README.md

@@ -14,7 +14,7 @@
   
 ## Content
 
-This directory contains a Clixon example which includes a simple example. It contains the following files:
+This directory contains a Clixon example used primarily for testing. It can be used as a basis for making new Clixon applications. But please consider also the minimal [hello](../hello) example as well. It contains the following files:
 * `example.xml`       The configuration file. See [yang/clixon-config@<date>.yang](../../yang/clixon-config@2019-03-05.yang) for the documentation of all available fields.
 * `clixon-example@2019-01-13.yang`      The yang spec of the example.
 * `example_cli.cli`   CLIgen specification.

example/main/example_backend.c

@@ -85,8 +85,7 @@ main_begin(clicon_handle    h,
 	   transaction_data td)
 {
     if (_transaction_log)
-	transaction_log(h, td, LOG_NOTICE, "begin");
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
-
     return 0;
 }
 /*! This is called on validate (and commit). Check validity of candidate
@@ -96,7 +95,7 @@ main_validate(clicon_handle    h,
 	      transaction_data td)
 {
     if (_transaction_log)
-	transaction_log(h, td, LOG_NOTICE, "validate");
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
     return 0;
 }
 
@@ -105,7 +104,7 @@ main_complete(clicon_handle    h,
 	      transaction_data td)
 {
     if (_transaction_log)
-	transaction_log(h, td, LOG_NOTICE, "complete");
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
     return 0;
 }
 
@@ -121,7 +120,8 @@ main_commit(clicon_handle    h,
     size_t  len;
 
     if (_transaction_log)
-	transaction_log(h, td, LOG_NOTICE, "commit");
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
+
     /* Get all added i/fs */
     if (xpath_vec_flag(target, "//interface", XML_FLAG_ADD, &vec, &len) < 0)
 	return -1;
@@ -134,12 +134,21 @@ main_commit(clicon_handle    h,
     return 0;
 }
 
+int
+main_revert(clicon_handle    h, 
+	    transaction_data td)
+{
+    if (_transaction_log)
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
+    return 0;
+}
+
 int
 main_end(clicon_handle    h, 
 	 transaction_data td)
 {
     if (_transaction_log)
-	transaction_log(h, td, LOG_NOTICE, "end");
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
     return 0;
 }
 
@@ -148,7 +157,7 @@ main_abort(clicon_handle    h,
 	   transaction_data td)
 {
     if (_transaction_log)
-	transaction_log(h, td, LOG_NOTICE, "abort");
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
     return 0;
 }
 
@@ -568,6 +577,7 @@ static clixon_plugin_api api = {
     .ca_trans_validate=main_validate,       /* trans validate */
     .ca_trans_complete=main_complete,       /* trans complete */
     .ca_trans_commit=main_commit,           /* trans commit */
+    .ca_trans_revert=main_revert,           /* trans revert */
     .ca_trans_end=main_end,                 /* trans end */
     .ca_trans_abort=main_abort              /* trans abort */
 };
@@ -594,7 +604,7 @@ clixon_plugin_init(clicon_handle h)
 	goto done;
     opterr = 0;
     optind = 1;
-    while ((c = getopt(argc, argv, "rsut")) != -1)
+    while ((c = getopt(argc, argv, "rsut:")) != -1)
 	switch (c) {
 	case 'r':
 	    _reset = 1;

example/main/example_backend_nacm.c

@@ -32,11 +32,16 @@
   ***** END LICENSE BLOCK *****
 
  * 
- * IETF yang routing example
+ * Secondary backend for testing more than one backend plugin, with the following 
- * Secondary backend for testing more than one backend plugin
+ * features:
+ * - nacm
+ * - transaction test
+ * The transaction test is test/test_transaction.sh where a user-error is triggered
+ * by this plugin if started with -- -t <xpath>. _transaction_xpath is then set
+ * and triggers a validation error if it matches. The error also toggles between
+ * validation and commit errors.
  */
 
-
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -55,6 +60,97 @@
 /* These include signatures for plugin and transaction callbacks. */
 #include <clixon/clixon_backend.h> 
 
+/*! Variable to control transaction logging (for debug)
+ * If set, call syslog for every transaction callback
+ */
+static int _transaction_log = 0;
+
+/*! Variable for failing validate and commit, if set, fail on validate vs commit
+ */
+static char * _transaction_xpath = NULL;
+static int  _transaction_error_toggle = 0; /* fail at validate vs commit */
+
+int
+nacm_begin(clicon_handle    h, 
+	   transaction_data td)
+{
+    if (_transaction_log)
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
+    return 0;
+}
+/*! This is called on validate (and commit). Check validity of candidate
+ */
+int
+nacm_validate(clicon_handle    h, 
+	      transaction_data td)
+{
+    if (_transaction_log){
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
+	if (_transaction_error_toggle==0 &&
+	    xpath_first(transaction_target(td), "%s", _transaction_xpath)){
+	    _transaction_error_toggle=1; /* toggle if triggered */
+	    clicon_err(OE_XML, 0, "User error");
+	    return -1; /* induce fail */
+	}
+    }
+    return 0;
+}
+
+int
+nacm_complete(clicon_handle    h, 
+	      transaction_data td)
+{
+    if (_transaction_log)
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
+    return 0;
+}
+
+/*! This is called on commit. Identify modifications and adjust machine state
+ */
+int
+nacm_commit(clicon_handle    h, 
+	    transaction_data td)
+{
+    cxobj  *target = transaction_target(td); /* wanted XML tree */
+
+    if (_transaction_log){
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
+	if (_transaction_error_toggle==1 &&
+	    xpath_first(target, "%s", _transaction_xpath)){
+	    _transaction_error_toggle=0; /* toggle if triggered */
+	    clicon_err(OE_XML, 0, "User error");
+	    return -1; /* induce fail */
+	}
+    }
+    return 0;
+}
+
+int
+nacm_revert(clicon_handle    h, 
+	    transaction_data td)
+{
+    if (_transaction_log)
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
+    return 0;
+}
+
+int
+nacm_end(clicon_handle    h, 
+	 transaction_data td)
+{
+    if (_transaction_log)
+	transaction_log(h, td, LOG_NOTICE, __FUNCTION__);
+    return 0;
+}
+
+int
+nacm_abort(clicon_handle    h, 
+	   transaction_data td)
+{
+    if (_transaction_log)
+	transaction_log(h, td, LOG_NOTICE,  __FUNCTION__);
+    return 0;
+}
 
 /*! Called to get NACM state data
  * @param[in]    h      Clicon handle
@@ -88,21 +184,21 @@ nacm_statedata(clicon_handle h,
     return retval;
 }
 
-int
-plugin_start(clicon_handle h)
-{
-    return 0;
-}
-
 clixon_plugin_api *clixon_plugin_init(clicon_handle h);
 
 static clixon_plugin_api api = {
     "nacm",             /* name */           /*--- Common fields.  ---*/
     clixon_plugin_init, /* init */
-    plugin_start,       /* start */
+    NULL,               /* start */
     NULL,               /* exit */
-    .ca_reset=NULL,               /* reset */
     .ca_statedata=nacm_statedata, /* statedata */
+    .ca_trans_begin=nacm_begin,             /* trans begin */
+    .ca_trans_validate=nacm_validate,       /* trans validate */
+    .ca_trans_complete=nacm_complete,       /* trans complete */
+    .ca_trans_commit=nacm_commit,           /* trans commit */
+    .ca_trans_revert=nacm_revert,           /* trans revert */
+    .ca_trans_end=nacm_end,                 /* trans end */
+    .ca_trans_abort=nacm_abort              /* trans abort */
 };
 
 /*! Backend plugin initialization
@@ -114,12 +210,33 @@ clixon_plugin_api *
 clixon_plugin_init(clicon_handle h)
 {
     char  *nacm_mode;
+    int    argc; /* command-line options (after --) */
+    char **argv;
+    int    c;
     
     clicon_debug(1, "%s backend nacm", __FUNCTION__);
+    /* Get user command-line options (after --) */
+    if (clicon_argv_get(h, &argc, &argv) < 0)
+	goto done;
+    opterr = 0;
+    optind = 1;
+    while ((c = getopt(argc, argv, "rsut:")) != -1)
+	switch (c) {
+	case 't': /* transaction log */
+	    _transaction_log = 1;
+	    _transaction_xpath = optarg;
+	    break;
+	}
+
     nacm_mode = clicon_option_str(h, "CLICON_NACM_MODE");
     if (nacm_mode==NULL || strcmp(nacm_mode, "disabled") == 0){
 	clicon_log(LOG_DEBUG, "%s CLICON_NACM_MODE not enabled: example nacm module disabled", __FUNCTION__);
+	/* Skip nacm module if not enabled _unless_ we use transaction tests */
+	if (_transaction_log == 0) 
 	    return NULL;
     }
+    /* Return plugin API */
     return &api;
+ done:
+    return NULL;
 }

lib/clixon/clixon_plugin.h

@@ -177,6 +177,7 @@ struct clixon_plugin_api{
 	    trans_cb_t       *cb_trans_validate; /* Transaction validation */
 	    trans_cb_t       *cb_trans_complete; /* Transaction validation complete */
 	    trans_cb_t       *cb_trans_commit;   /* Transaction commit */
+	    trans_cb_t       *cb_trans_revert;   /* Transaction revert */
 	    trans_cb_t       *cb_trans_end;	 /* Transaction completed  */
     	    trans_cb_t       *cb_trans_abort;	 /* Transaction aborted */    
 
@@ -195,6 +196,7 @@ struct clixon_plugin_api{
 #define ca_trans_validate u.cau_backend.cb_trans_validate
 #define ca_trans_complete u.cau_backend.cb_trans_complete
 #define ca_trans_commit   u.cau_backend.cb_trans_commit
+#define ca_trans_revert   u.cau_backend.cb_trans_revert
 #define ca_trans_end      u.cau_backend.cb_trans_end
 #define ca_trans_abort    u.cau_backend.cb_trans_abort
 

test/test_transaction.sh

@@ -1,10 +1,20 @@
 #!/bin/bash
 # Transaction functionality
-# The test uses a backend that logs to a file and a netconf client to push
+# The test uses two backend plugins (main and nacm) that logs to a file and a
-# changes. The main example backend plugin logs to the file, and the test
+# netconf client to push operation. The tests then look at the log.
-# verifies the logs.
+# The tests are as follows (first five only callbacks per se; then data vector tests)
-# The yang is a list with three members, so that you can do add/delete/change
+# 1. Validate-only transaction
-# in a single go.
+# 2. Commit transaction
+# 3. Validate system-error (invalid type detected by system)
+# 4. Validate user-error (invalidation by user callback)
+# 5. Commit user-error (invalidation by user callback)
+# -- to here only basic callback tests (that they occur). Below transaction data
+# 6. Detailed transaction vector add/del/change tests
+# For the last test, the yang is a list with three members, so that you can do
+# add/delete/change in a single go.
+# The user-error uses a trick feature in the example nacm plugin which is started
+# with an "error-trigger" xpath which triggers an error. This also toggles between
+# validation and commit errors
 
 # Magic line must be first in script (see README.md)
 s="$_" ; . ./lib.sh || if [ "$s" = $0 ]; then exit 0; else return 0; fi
@@ -19,6 +29,9 @@ fyang=$dir/trans.yang
 flog=$dir/backend.log
 touch $flog
 
+# Used as a trigger for user-validittion errors, eg <a>$errnr</a> is invalid
+errnr=42
+
 cat <<EOF > $fyang
 module trans{
    yang-version 1.1;
@@ -31,8 +44,10 @@ module trans{
         type int32;
       }
       leaf b {
-        description "change this";
+        description "change this (also use to check invalid)";
-        type int32;
+        type int32{
+          range "0..100";
+        }
       }
       leaf c {
         description "del this";
@@ -54,7 +69,7 @@ cat <<EOF > $cfg
   <CLICON_YANG_MAIN_FILE>$fyang</CLICON_YANG_MAIN_FILE>
   <CLICON_CLISPEC_DIR>/usr/local/lib/$APPNAME/clispec</CLICON_CLISPEC_DIR>
   <CLICON_BACKEND_DIR>/usr/local/lib/$APPNAME/backend</CLICON_BACKEND_DIR>
-  <CLICON_BACKEND_REGEXP>example_backend.so$</CLICON_BACKEND_REGEXP>
+  <!--CLICON_BACKEND_REGEXP>example_backend.so$</CLICON_BACKEND_REGEXP-->
   <CLICON_NETCONF_DIR>/usr/local/lib/$APPNAME/netconf</CLICON_NETCONF_DIR>
   <CLICON_RESTCONF_DIR>/usr/local/lib/$APPNAME/restconf</CLICON_RESTCONF_DIR>
   <CLICON_CLI_DIR>/usr/local/lib/$APPNAME/cli</CLICON_CLI_DIR>
@@ -70,8 +85,9 @@ EOF
 # Check statements in log
 checklog(){
     s=$1 # statement
+    l0=$2 # linenr
     new "Check $s in log"
-    t=$(grep "$s" $flog)
+    t=$(grep -n "transaction_log $s" $flog)
     if [ -z "$t" ]; then
 	echo -e "\e[31m\nError in Test$testnr [$testname]:"
 	if [ $# -gt 0 ]; then 
@@ -81,9 +97,19 @@ checklog(){
 	echo -e "\e[0m"
 	exit -1
     fi
+    l1=$(echo "$t" | awk -F ":" '{print $1}')
+    if [ $l1 -ne $l0 ]; then
+	echo -e "\e[31m\nError in Test$testnr [$testname]:"
+	if [ $# -gt 0 ]; then 
+	    echo "Expected match on line $l0, found on $l1"
+	    echo
+	fi
+	echo -e "\e[0m"
+	exit -1
+    fi
 }
 
-new "test params: -f $cfg -l f$flog -- -t"
+new "test params: -f $cfg -l f$flog -- -t /x/y[a=$errnr]" # Fail on this
 # Bring your own backend
 if [ $BE -ne 0 ]; then
     # kill old backend (if any)
@@ -92,47 +118,190 @@ if [ $BE -ne 0 ]; then
     if [ $? -ne 0 ]; then
 	err
     fi
-    new "start backend  -s init -f $cfg -l f$flog -- -t"
+    new "start backend  -s init -f $cfg -l f$flog -- -t /x/y[a=$errnr]"
-    start_backend -s init -f $cfg -l f$flog -- -t  # -t means transaction logging
+    start_backend -s init -f $cfg -l f$flog -- -t /x/y[a=$errnr] # -t means transaction logging
     new "waiting"
     sleep $RCWAIT
 fi
 
-new "netconf base config (0) a,b,c"
+let nr=1
-expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><edit-config><target><candidate/></target><config><x xmlns="urn:example:clixon"><y><a>0</a><b>0</b><c>0</c></y></x></config></edit-config></rpc>]]>]]>' '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+
+new "Basic transaction to add top-level x"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><edit-config><target><candidate/></target><config><x xmlns='urn:example:clixon'><y><a>$nr</a></y></x></config></edit-config></rpc>]]>]]>" '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+
+new "Commit base"
+expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><commit/></rpc>]]>]]>' '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+
+let line=12 # Skipping basic transaction
+
+# 1. validate(-only) transaction
+let nr++
+let line
+new "1. Validate-only transaction"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><edit-config><target><candidate/></target><config><x xmlns='urn:example:clixon'><y><a>$nr</a></y></x></config></edit-config></rpc>]]>]]>" '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+
+new "Validate-only validate"
+expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><validate><source><candidate/></source></validate></rpc>]]>]]>' '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+
+xml="<y><a>$nr</a></y>"
+for op in begin validate complete end; do
+    checklog "$nr main_$op add: $xml" $line
+    let line++
+    checklog "$nr nacm_$op add: $xml" $line
+    let line++
+done
+
+new "Validate-only discard-changes"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><discard-changes/></rpc>]]>]]>" "^<rpc-reply><ok/></rpc-reply>]]>]]>$"
+
+# 2. Commit transaction
+let nr++
+new "2. Commit transaction config"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><edit-config><target><candidate/></target><config><x xmlns='urn:example:clixon'><y><a>$nr</a></y></x></config></edit-config></rpc>]]>]]>" '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+
+new "Commit transaction: commit"
+expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><commit/></rpc>]]>]]>' '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+
+xml="<y><a>$nr</a></y>"
+for op in begin validate complete commit end; do
+    checklog "$nr main_$op add: $xml" $line
+    let line++
+    checklog "$nr nacm_$op add: $xml" $line
+    let line++
+done
+
+# 3. Validate only system-error (invalid type detected by system)
+let nr++
+new "3. Validate system-error config (9999 not in range)"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><edit-config><target><candidate/></target><config><x xmlns='urn:example:clixon'><y><a>$nr</a><b>9999</b></y></x></config></edit-config></rpc>]]>]]>" '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+
+new "Validate system-error validate (should fail)"
+expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><validate><source><candidate/></source></validate></rpc>]]>]]>' '^<rpc-reply><rpc-error><error-type>application</error-type><error-tag>bad-element</error-tag><error-info><bad-element>b</bad-element></error-info><error-severity>error</error-severity><error-message>Number out of range: 9999</error-message></rpc-error></rpc-reply>]]>]]>$'
+
+new "Validate system-error discard-changes"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><discard-changes/></rpc>]]>]]>" "^<rpc-reply><ok/></rpc-reply>]]>]]>$"
+
+for op in begin abort; do
+    checklog "$nr main_$op add: <y><a>$nr</a><b>9999</b></y>" $line
+    let line++
+    checklog "$nr nacm_$op add: <y><a>$nr</a><b>9999</b></y>" $line
+    let line++
+done
+
+# 4. Validate only user-error (invalidation by user callback)
+let nr++
+new "4. Validate user-error config ($errnr is invalid)"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><edit-config><target><candidate/></target><config><x xmlns='urn:example:clixon'><y><a>$errnr</a></y></x></config></edit-config></rpc>]]>]]>" '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+
+new "Validate user-error validate (should fail)"
+expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><validate><source><candidate/></source></validate></rpc>]]>]]>' '^<rpc-reply><rpc-error><error-type>application</error-type><error-tag>operation-failed</error-tag><error-severity>error</error-severity><error-message>User error</error-message></rpc-error></rpc-reply>]]>]]>$'
+
+new "Validate user-error discard-changes"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><discard-changes/></rpc>]]>]]>" "^<rpc-reply><ok/></rpc-reply>]]>]]>$"
+
+for op in begin validate; do
+    checklog "$nr main_$op add: <y><a>$errnr</a></y>" $line
+    let line++
+    checklog "$nr nacm_$op add: <y><a>$errnr</a></y>" $line
+    let line++
+done
+let line++ # error message
+for op in abort; do
+    checklog "$nr main_$op add: <y><a>$errnr</a></y>" $line
+    let line++
+    checklog "$nr nacm_$op add: <y><a>$errnr</a></y>" $line
+    let line++
+done
+
+# 5. Commit user-error (invalidation by user callback)
+# XXX Note Validate-only user-error must immediately preceede this due to toggling
+# in nacm/transaction example test module
+let nr++
+new "5. Commit user-error ($errnr is invalid)"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><edit-config><target><candidate/></target><config><x xmlns='urn:example:clixon'><y><a>$errnr</a></y></x></config></edit-config></rpc>]]>]]>" '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+
+new "Commit user-error commit"
+expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><commit/></rpc>]]>]]>' '^<rpc-reply><rpc-error><error-type>application</error-type><error-tag>operation-failed</error-tag><error-severity>error</error-severity><error-message>User error</error-message></rpc-error></rpc-reply>]]>]]>$'
+
+new "Commit user-error discard-changes"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><discard-changes/></rpc>]]>]]>" "^<rpc-reply><ok/></rpc-reply>]]>]]>$"
+
+for op in begin validate complete commit; do
+    checklog "$nr main_$op add: <y><a>$errnr</a></y>" $line
+    let line++
+    checklog "$nr nacm_$op add: <y><a>$errnr</a></y>" $line
+    let line++
+done
+let line++ # error message
+checklog "$nr main_revert add: <y><a>$errnr</a></y>" $line
+let line++
+for op in abort; do
+    checklog "$nr main_$op add: <y><a>$errnr</a></y>" $line
+    let line++
+    checklog "$nr nacm_$op add: <y><a>$errnr</a></y>" $line
+    let line++
+done
+
+# 6. Detailed transaction vector add/del/change tests
+let nr++
+let base=nr
+new "Add base <a>$base entry"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><edit-config><target><candidate/></target><config><x xmlns='urn:example:clixon'><y><a>$base</a><b>0</b><c>0</c></y></x></config></edit-config></rpc>]]>]]>" '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
 
 new "netconf commit base"
 expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><commit/></rpc>]]>]]>' '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
 #Ignore
+let line+=10
 
-new "netconf mixed change: change b, del c, add d"
+let nr++
-expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><edit-config><target><candidate/></target><config><x xmlns="urn:example:clixon"><y><a>0</a><b>42</b><d>0</d></y></x></config></edit-config></rpc>]]>]]>' '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+new "6. netconf mixed change: change b, del c, add d"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><edit-config><target><candidate/></target><config><x xmlns='urn:example:clixon'><y><a>$base</a><b>42</b><d>0</d></y></x></config></edit-config></rpc>]]>]]>" '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
 
 new "netconf commit change"
 expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><commit/></rpc>]]>]]>' '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
 
-# Check complete transaction 2:
+# Check complete transaction $nr:
 for op in begin validate complete commit; do
-    checklog "transaction_log 2 $op add: <d>0</d>"
+    checklog "$nr main_$op add: <d>0</d>" $line
-    checklog "transaction_log 2 $op change: <b>0</b><b>42</b>"
+    let line++
+    checklog "$nr main_$op change: <b>0</b><b>42</b>" $line
+    let line++
+    checklog "$nr nacm_$op add: <d>0</d>" $line
+    let line++
+    checklog "$nr nacm_$op change: <b>0</b><b>42</b>" $line
+    let line++
 done
-# End is special
-checklog "transaction_log 2 end add: <d>0</d>"
-checklog "transaction_log 2 end change: <b>42</b>"
 
-new "netconf config (1) end-points a,d "
+# End is special because change does not haveold element
-expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><edit-config><target><candidate/></target><config><x xmlns="urn:example:clixon"><y><a>1</a><d>1</d></y></x></config></edit-config></rpc>]]>]]>' '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+checklog "$nr main_end add: <d>0</d>" $line
+let line++
+checklog "$nr main_end change: <b>42</b>" $line
+let line+=3 # skip nacm
+
+let nr++
+let base=nr
+new "Add base <a>$base entry"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><edit-config><target><candidate/></target><config><x xmlns='urn:example:clixon'><y><a>$base</a><d>1</d></y></x></config></edit-config></rpc>]]>]]>" '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+
+new "netconf commit base"
+expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><commit/></rpc>]]>]]>' '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+let line+=10
+
+# Variant check that only b,c
+let nr++
+new "7. netconf insert b,c between end-points"
+expecteof "$clixon_netconf -qf $cfg" 0 "<rpc><edit-config><target><candidate/></target><config><x xmlns='urn:example:clixon'><y><a>$base</a><b>1</b><c>1</c></y></x></config></edit-config></rpc>]]>]]>" '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
 
 new "netconf commit base"
 expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><commit/></rpc>]]>]]>' '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
 
-new "netconf insert b,c between end-points"
+# check complete
-expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><edit-config><target><candidate/></target><config><x xmlns="urn:example:clixon"><y><a>1</a><b>1</b><c>1</c></y></x></config></edit-config></rpc>]]>]]>' '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+for op in begin validate complete commit end; do
-
+    checklog "$nr main_$op add: <b>1</b><c>1</c>" $line
-new "netconf commit base"
+    let line++
-expecteof "$clixon_netconf -qf $cfg" 0 '<rpc><commit/></rpc>]]>]]>' '^<rpc-reply><ok/></rpc-reply>]]>]]>$'
+    checklog "$nr nacm_$op add: <b>1</b><c>1</c>" $line
-
+    let line++
-checklog "transaction_log 4 validate add: <b>1</b><c>1</c>"
+done
 
 if [ $BE -eq 0 ]; then
     exit # BE