[ovs-dev] [PATCH monitor_cond 03/12] ovsdb: generate update notifications for monitor_cond session
Liran Schour
lirans at il.ibm.com
Tue Jan 5 13:13:56 UTC 2016
Hold session's conditions in ovsdb_monitor_session_conditon. Pass it
to ovsdb_monitor for generating "update2" notifications.
Add functions that can generate "update2" notification for a
"monitor_cond" session.
json_cache for will be enabled only for session's with empty condition.
"monitor_cond" and "monitor_cond_change" are RFC 7047 extensions
deescribed by ovsdb-server(1) manpage.
Signed-off-by: Liran Schour <lirans at il.ibm.com>
---
ovsdb/jsonrpc-server.c | 59 +++++++++++---
ovsdb/monitor.c | 208 +++++++++++++++++++++++++++++++++++++++++++++--
ovsdb/monitor.h | 37 ++++++++-
ovsdb/ovsdb-server.1.in | 212 ++++++++++++++++++++++++++++++++++++++++++++----
4 files changed, 477 insertions(+), 39 deletions(-)
diff --git a/ovsdb/jsonrpc-server.c b/ovsdb/jsonrpc-server.c
index 2065702..e4500da 100644
--- a/ovsdb/jsonrpc-server.c
+++ b/ovsdb/jsonrpc-server.c
@@ -28,6 +28,7 @@
#include "ovsdb-error.h"
#include "ovsdb-parser.h"
#include "ovsdb.h"
+#include "condition.h"
#include "poll-loop.h"
#include "reconnect.h"
#include "row.h"
@@ -85,7 +86,7 @@ static void ovsdb_jsonrpc_trigger_complete_done(
/* Monitors. */
static struct jsonrpc_msg *ovsdb_jsonrpc_monitor_create(
struct ovsdb_jsonrpc_session *, struct ovsdb *, struct json *params,
- enum ovsdb_monitor_version, const struct json *request_id);
+ enum ovsdb_monitor_version, bool, const struct json *request_id);
static struct jsonrpc_msg *ovsdb_jsonrpc_monitor_cancel(
struct ovsdb_jsonrpc_session *,
struct json_array *params,
@@ -849,14 +850,18 @@ ovsdb_jsonrpc_session_got_request(struct ovsdb_jsonrpc_session *s,
reply = execute_transaction(s, db, request);
}
} else if (!strcmp(request->method, "monitor") ||
- (monitor2_enable__ && !strcmp(request->method, "monitor2"))) {
+ (monitor2_enable__ && !strcmp(request->method, "monitor2")) ||
+ !strcmp(request->method, "monitor_cond")) {
struct ovsdb *db = ovsdb_jsonrpc_lookup_db(s, request, &reply);
if (!reply) {
int l = strlen(request->method) - strlen("monitor");
enum ovsdb_monitor_version version = l ? OVSDB_MONITOR_V2
: OVSDB_MONITOR_V1;
reply = ovsdb_jsonrpc_monitor_create(s, db, request->params,
- version, request->id);
+ version,
+ !strcmp(request->method,
+ "monitor_cond"),
+ request->id);
}
} else if (!strcmp(request->method, "monitor_cancel")) {
reply = ovsdb_jsonrpc_monitor_cancel(s, json_array(request->params),
@@ -1048,6 +1053,7 @@ struct ovsdb_jsonrpc_monitor {
uint64_t unflushed; /* The first transaction that has not been
flushed to the jsonrpc remote client. */
enum ovsdb_monitor_version version;
+ struct ovsdb_monitor_session_condition *condition;/* Session's condition */
};
static struct ovsdb_jsonrpc_monitor *
@@ -1075,21 +1081,29 @@ parse_bool(struct ovsdb_parser *parser, const char *name, bool default_value)
}
static struct ovsdb_error * OVS_WARN_UNUSED_RESULT
-ovsdb_jsonrpc_parse_monitor_request(struct ovsdb_monitor *dbmon,
- const struct ovsdb_table *table,
- const struct json *monitor_request,
- size_t *allocated_columns)
+ovsdb_jsonrpc_parse_monitor_request(
+ struct ovsdb_monitor *dbmon,
+ const struct ovsdb_table *table,
+ bool conditional,
+ struct ovsdb_monitor_session_condition *cond,
+ const struct json *monitor_request,
+ size_t *allocated_columns)
{
const struct ovsdb_table_schema *ts = table->schema;
enum ovsdb_monitor_selection select;
- const struct json *columns, *select_json;
+ const struct json *columns, *select_json, *where = NULL;
struct ovsdb_parser parser;
struct ovsdb_error *error;
ovsdb_parser_init(&parser, monitor_request, "table %s", ts->name);
+ if (conditional) {
+ where = ovsdb_parser_member(&parser, "where", OP_ARRAY | OP_OPTIONAL);
+ }
columns = ovsdb_parser_member(&parser, "columns", OP_ARRAY | OP_OPTIONAL);
+
select_json = ovsdb_parser_member(&parser, "select",
OP_OBJECT | OP_OPTIONAL);
+
error = ovsdb_parser_finish(&parser);
if (error) {
return error;
@@ -1156,6 +1170,12 @@ ovsdb_jsonrpc_parse_monitor_request(struct ovsdb_monitor *dbmon,
}
}
}
+ if (conditional) {
+ error = ovsdb_monitor_table_condition_add(cond, table, where);
+ if (error) {
+ return error;
+ }
+ }
return NULL;
}
@@ -1164,6 +1184,7 @@ static struct jsonrpc_msg *
ovsdb_jsonrpc_monitor_create(struct ovsdb_jsonrpc_session *s, struct ovsdb *db,
struct json *params,
enum ovsdb_monitor_version version,
+ bool conditional,
const struct json *request_id)
{
struct ovsdb_jsonrpc_monitor *m = NULL;
@@ -1194,6 +1215,9 @@ ovsdb_jsonrpc_monitor_create(struct ovsdb_jsonrpc_session *s, struct ovsdb *db,
m->session = s;
m->db = db;
m->dbmon = ovsdb_monitor_create(db, m);
+ if (conditional) {
+ m->condition = ovsdb_monitor_session_condition_create();
+ }
m->unflushed = 0;
m->version = version;
hmap_insert(&s->monitors, &m->node, json_hash(monitor_id, 0));
@@ -1223,14 +1247,18 @@ ovsdb_jsonrpc_monitor_create(struct ovsdb_jsonrpc_session *s, struct ovsdb *db,
for (i = 0; i < array->n; i++) {
error = ovsdb_jsonrpc_parse_monitor_request(
- m->dbmon, table, array->elems[i], &allocated_columns);
+ m->dbmon, table, conditional, m->condition,
+ array->elems[i], &allocated_columns);
if (error) {
goto error;
}
}
} else {
- error = ovsdb_jsonrpc_parse_monitor_request(
- m->dbmon, table, mr_value, &allocated_columns);
+ error = ovsdb_jsonrpc_parse_monitor_request(m->dbmon, table,
+ conditional,
+ m->condition,
+ mr_value,
+ &allocated_columns);
if (error) {
goto error;
}
@@ -1254,6 +1282,10 @@ ovsdb_jsonrpc_monitor_create(struct ovsdb_jsonrpc_session *s, struct ovsdb *db,
m->dbmon = dbmon;
}
+ if (conditional) {
+ /* Only now we can bind the session_condition to ovsdb_monitor. */
+ ovsdb_monitor_session_condition_bind(m->condition, dbmon);
+ }
ovsdb_monitor_get_initial(m->dbmon);
json = ovsdb_jsonrpc_monitor_compose_update(m, true);
json = json ? json : json_object_create();
@@ -1306,7 +1338,7 @@ ovsdb_jsonrpc_monitor_compose_update(struct ovsdb_jsonrpc_monitor *m,
bool initial)
{
return ovsdb_monitor_get_update(m->dbmon, initial, &m->unflushed,
- m->version);
+ m->condition, m->version);
}
static bool
@@ -1329,6 +1361,9 @@ ovsdb_jsonrpc_monitor_destroy(struct ovsdb_jsonrpc_monitor *m)
json_destroy(m->monitor_id);
hmap_remove(&m->session->monitors, &m->node);
ovsdb_monitor_remove_jsonrpc_monitor(m->dbmon, m);
+ if (m->condition) {
+ ovsdb_monitor_session_condition_destroy(m->condition);
+ }
free(m);
}
diff --git a/ovsdb/monitor.c b/ovsdb/monitor.c
index 51f4e09..5e3117a 100644
--- a/ovsdb/monitor.c
+++ b/ovsdb/monitor.c
@@ -27,6 +27,7 @@
#include "ovsdb-parser.h"
#include "ovsdb.h"
#include "row.h"
+#include "condition.h"
#include "simap.h"
#include "hash.h"
#include "table.h"
@@ -41,6 +42,20 @@
static const struct ovsdb_replica_class ovsdb_jsonrpc_replica_class;
static struct hmap ovsdb_monitors = HMAP_INITIALIZER(&ovsdb_monitors);
+/* Keep state of session's conditions */
+struct ovsdb_monitor_session_condition {
+ bool can_cache;
+ struct shash tables; /* Contains
+ * "struct ovsdb_monitor_table_condition *"s. */
+};
+
+/* Monitored table session's conditions */
+struct ovsdb_monitor_table_condition {
+ struct ovsdb_monitor_table *mt;
+ struct ovsdb_condition old_condition;
+ struct ovsdb_condition new_condition;
+};
+
/* Backend monitor.
*
* ovsdb_monitor keep track of the ovsdb changes.
@@ -55,6 +70,8 @@ struct ovsdb_monitor {
uint64_t n_transactions; /* Count number of committed transactions. */
struct hmap_node hmap_node; /* Elements within ovsdb_monitors. */
struct hmap json_cache; /* Contains "ovsdb_monitor_json_cache_node"s.*/
+ /* tmp pointer for composing update */
+ const struct ovsdb_monitor_session_condition *condition;
};
/* A json object of updates between 'from_txn' and 'dbmon->n_transactions'
@@ -107,6 +124,7 @@ struct ovsdb_monitor_changes {
/* A particular table being monitored. */
struct ovsdb_monitor_table {
const struct ovsdb_table *table;
+ const struct ovsdb_monitor *dbmon;
/* This is the union (bitwise-OR) of the 'select' values in all of the
* members of 'columns' below. */
@@ -121,6 +139,10 @@ struct ovsdb_monitor_table {
/* Contains 'ovsdb_monitor_changes' indexed by 'transaction'. */
struct hmap changes;
+
+ /* Temp pointers to conditions for composing update */
+ struct ovsdb_condition *old_condition;
+ struct ovsdb_condition *new_condition;
};
typedef struct json *
@@ -348,6 +370,7 @@ ovsdb_monitor_add_table(struct ovsdb_monitor *m,
mt = xzalloc(sizeof *mt);
mt->table = table;
+ mt->dbmon = m;
shash_add(&m->tables, table->schema->name, mt);
hmap_init(&mt->changes);
mt->columns_index_map =
@@ -488,6 +511,162 @@ ovsdb_monitor_row_update_type(bool initial, const bool old, const bool new)
: !new ? OJMS_DELETE
: OJMS_MODIFY;
}
+
+/* Returnes an empty allocated session's condition state holder */
+struct ovsdb_monitor_session_condition *
+ovsdb_monitor_session_condition_create(void)
+{
+ struct ovsdb_monitor_session_condition *condition;
+
+ condition = xzalloc(sizeof *condition);
+ shash_init(&condition->tables);
+ condition->can_cache = true;
+
+ return condition;
+}
+
+void
+ovsdb_monitor_session_condition_destroy(
+ struct ovsdb_monitor_session_condition *condition)
+{
+ struct shash_node *node, *next;
+
+ SHASH_FOR_EACH_SAFE (node, next, &condition->tables) {
+ struct ovsdb_monitor_table_condition *mtc = node->data;
+
+ ovsdb_condition_destroy(&mtc->new_condition);
+ ovsdb_condition_destroy(&mtc->old_condition);
+ shash_delete(&condition->tables, node);
+ free(mtc);
+ }
+ free(condition);
+}
+
+/* Bind session's condition to a specific ovsdb_monitor */
+void ovsdb_monitor_session_condition_bind(
+ const struct ovsdb_monitor_session_condition *condition,
+ const struct ovsdb_monitor *dbmon)
+{
+ struct shash_node *node;
+
+ SHASH_FOR_EACH (node, &condition->tables) {
+ struct ovsdb_monitor_table_condition *mtc = node->data;
+ struct ovsdb_monitor_table *mt;
+
+ mt = shash_find_data(&dbmon->tables, node->name);
+ mtc->mt = mt;
+ }
+}
+
+struct ovsdb_error *
+ovsdb_monitor_table_condition_add(
+ struct ovsdb_monitor_session_condition *condition,
+ const struct ovsdb_table *table,
+ const struct json *json_cnd)
+{
+ struct ovsdb_monitor_table_condition *mtc;
+ struct ovsdb_error *error;
+
+ mtc = xzalloc(sizeof *mtc);
+ shash_add(&condition->tables, table->schema->name, mtc);
+ ovsdb_condition_init(&mtc->old_condition);
+ ovsdb_condition_init(&mtc->new_condition);
+
+ if (json_cnd) {
+ error = ovsdb_condition_from_json(table->schema,
+ json_cnd,
+ NULL,
+ &mtc->old_condition);
+ if (error) {
+ return ovsdb_syntax_error(json_cnd,
+ NULL, "array of conditons expected");
+ }
+ }
+ ovsdb_condition_clone(&mtc->new_condition, &mtc->old_condition);
+
+ if (!ovsdb_condition_empty(&mtc->old_condition)) {
+ condition->can_cache = false;
+ }
+
+ return NULL;
+}
+
+/* Set session's condition in this ovsdb_monitor */
+static void
+ovsdb_monitor_set_condition(
+ struct ovsdb_monitor *dbmon,
+ const struct ovsdb_monitor_session_condition *condition)
+{
+ struct shash_node *node;
+
+ if (condition) {
+ dbmon->condition = condition;
+ SHASH_FOR_EACH (node, &condition->tables) {
+ struct ovsdb_monitor_table_condition *mtc = node->data;
+
+ mtc->mt->old_condition = &mtc->old_condition;
+ mtc->mt->new_condition = &mtc->new_condition;
+ }
+ }
+}
+
+static void
+ovsdb_monitor_unset_condition(struct ovsdb_monitor *dbmon)
+{
+ dbmon->condition = NULL;
+}
+
+static enum ovsdb_monitor_selection
+ovsdb_monitor_row_update_type_condition(const struct ovsdb_monitor_table *mt,
+ bool initial,
+ const struct ovsdb_datum *old,
+ const struct ovsdb_datum *new,
+ const bool index_map)
+{
+ unsigned int *columns_index_map = index_map ? mt->columns_index_map
+ : NULL;
+ enum ovsdb_monitor_selection type =
+ ovsdb_monitor_row_update_type(initial, old, new);
+
+ if (mt->dbmon->condition &&
+ (!ovsdb_condition_empty(mt->old_condition) &&
+ !ovsdb_condition_empty(mt->new_condition))) {
+ bool old_cond = !old ? false
+ : ovsdb_condition_evaluate_or_datum(old,
+ mt->old_condition,
+ columns_index_map);
+ bool new_cond = !new ? false
+ : ovsdb_condition_evaluate_or_datum(new,
+ mt->new_condition,
+ columns_index_map);
+
+ if (!old_cond && !new_cond) {
+ type = OJMS_NONE;
+ }
+
+ switch (type) {
+ case OJMS_INITIAL:
+ case OJMS_INSERT:
+ if (!new_cond) {
+ type = OJMS_NONE;
+ }
+ break;
+ case OJMS_MODIFY:
+ type = !old_cond ? OJMS_INSERT : !new_cond
+ ? OJMS_DELETE : OJMS_MODIFY;
+ break;
+ case OJMS_DELETE:
+ if (!old_cond) {
+ type = OJMS_NONE;
+ }
+ break;
+ case OJMS_NONE:
+ break;
+ }
+ }
+ return type;
+}
+
static bool
ovsdb_monitor_row_skip_update(const struct ovsdb_monitor_table *mt,
const struct ovsdb_monitor_row *row,
@@ -600,7 +779,8 @@ ovsdb_monitor_compose_row_update2(
struct json *row_update2, *diff_json;
size_t i;
- type = ovsdb_monitor_row_update_type(initial, row->old, row->new);
+ type = ovsdb_monitor_row_update_type_condition(mt, initial,
+ row->old, row->new, true);
if (ovsdb_monitor_row_skip_update(mt, row, type, changed)) {
return NULL;
}
@@ -728,19 +908,24 @@ ovsdb_monitor_compose_update(struct ovsdb_monitor *dbmon,
* be used as part of the initial reply to a "monitor" request, false if it is
* going to be used as part of an "update" notification. */
struct json *
-ovsdb_monitor_get_update(struct ovsdb_monitor *dbmon,
- bool initial, uint64_t *unflushed,
- enum ovsdb_monitor_version version)
+ovsdb_monitor_get_update(
+ struct ovsdb_monitor *dbmon,
+ bool initial, uint64_t *unflushed,
+ const struct ovsdb_monitor_session_condition *condition,
+ enum ovsdb_monitor_version version)
{
- struct ovsdb_monitor_json_cache_node *cache_node;
+ struct ovsdb_monitor_json_cache_node *cache_node = NULL;
struct shash_node *node;
struct json *json;
uint64_t prev_txn = *unflushed;
uint64_t next_txn = dbmon->n_transactions + 1;
+ ovsdb_monitor_set_condition(dbmon, condition);
/* Return a clone of cached json if one exists. Otherwise,
* generate a new one and add it to the cache. */
- cache_node = ovsdb_monitor_json_cache_search(dbmon, version, prev_txn);
+ if (condition && condition->can_cache) {
+ cache_node = ovsdb_monitor_json_cache_search(dbmon, version, prev_txn);
+ }
if (cache_node) {
json = cache_node->json ? json_clone(cache_node->json) : NULL;
} else {
@@ -752,7 +937,9 @@ ovsdb_monitor_get_update(struct ovsdb_monitor *dbmon,
json = ovsdb_monitor_compose_update(dbmon, initial, prev_txn,
ovsdb_monitor_compose_row_update2);
}
- ovsdb_monitor_json_cache_insert(dbmon, version, prev_txn, json);
+ if (condition && condition->can_cache) {
+ ovsdb_monitor_json_cache_insert(dbmon, version, prev_txn, json);
+ }
}
/* Maintain transaction id of 'changes'. */
@@ -763,6 +950,7 @@ ovsdb_monitor_get_update(struct ovsdb_monitor *dbmon,
ovsdb_monitor_table_track_changes(mt, next_txn);
}
*unflushed = next_txn;
+ ovsdb_monitor_unset_condition(dbmon);
return json;
}
@@ -890,6 +1078,11 @@ ovsdb_monitor_changes_classify(enum ovsdb_monitor_selection type,
return OVSDB_CHANGES_NO_EFFECT;
}
+ /* On conditional monitor MODIFY might be INSERT or DELETE */
+ if (type == OJMS_MODIFY) {
+ type |= OJMS_INSERT | OJMS_DELETE;
+ }
+
return (mt->select & type)
? OVSDB_CHANGES_REQUIRE_EXTERNAL_UPDATE
: OVSDB_CHANGES_REQUIRE_INTERNAL_UPDATE;
@@ -922,6 +1115,7 @@ ovsdb_monitor_change_cb(const struct ovsdb_row *old,
enum ovsdb_monitor_selection type;
type = ovsdb_monitor_row_update_type(false, old, new);
+
efficacy = ovsdb_monitor_changes_classify(type, mt, changed);
if (efficacy > OVSDB_CHANGES_NO_EFFECT) {
ovsdb_monitor_changes_update(old, new, mt, changes);
diff --git a/ovsdb/monitor.h b/ovsdb/monitor.h
index d6e9635..d4063f7 100644
--- a/ovsdb/monitor.h
+++ b/ovsdb/monitor.h
@@ -19,8 +19,11 @@
struct ovsdb_monitor;
struct ovsdb_jsonrpc_monitor;
+struct ovsdb_monitor_session_condition;
+struct ovsdb_condition;
enum ovsdb_monitor_selection {
+ OJMS_NONE = 0, /* None for this iteration */
OJMS_INITIAL = 1 << 0, /* All rows when monitor is created. */
OJMS_INSERT = 1 << 1, /* New rows. */
OJMS_DELETE = 1 << 2, /* Deleted rows. */
@@ -64,17 +67,43 @@ const char * OVS_WARN_UNUSED_RESULT
ovsdb_monitor_table_check_duplicates(struct ovsdb_monitor *,
const struct ovsdb_table *);
-struct json *ovsdb_monitor_get_update(struct ovsdb_monitor *dbmon,
- bool initial,
- uint64_t *unflushed_transaction,
- enum ovsdb_monitor_version version);
+struct json *ovsdb_monitor_get_update(
+ struct ovsdb_monitor *dbmon,
+ bool initial,
+ uint64_t *unflushed_transaction,
+ const struct ovsdb_monitor_session_condition *condition,
+ enum ovsdb_monitor_version version);
void ovsdb_monitor_table_add_select(struct ovsdb_monitor *dbmon,
const struct ovsdb_table *table,
enum ovsdb_monitor_selection select);
+struct ovsdb_condition *
+ovsdb_monitor_table_get_condition(struct ovsdb_monitor *dbmon,
+ const struct ovsdb_table *table);
+
+void ovsdb_monitor_table_set_conditional(struct ovsdb_monitor *dbmon,
+ const struct ovsdb_table *table);
+
bool ovsdb_monitor_needs_flush(struct ovsdb_monitor *dbmon,
uint64_t next_transaction);
void ovsdb_monitor_get_initial(const struct ovsdb_monitor *dbmon);
+
+struct ovsdb_monitor_session_condition *
+ovsdb_monitor_session_condition_create(void);
+
+void
+ovsdb_monitor_session_condition_destroy(
+ struct ovsdb_monitor_session_condition *condition);
+struct ovsdb_error *
+ovsdb_monitor_table_condition_add(
+ struct ovsdb_monitor_session_condition *condition,
+ const struct ovsdb_table *table,
+ const struct json *json_cnd);
+
+void ovsdb_monitor_session_condition_bind(
+ const struct ovsdb_monitor_session_condition *,
+ const struct ovsdb_monitor *);
+
#endif
diff --git a/ovsdb/ovsdb-server.1.in b/ovsdb/ovsdb-server.1.in
index 6c85729..33dc1ab 100644
--- a/ovsdb/ovsdb-server.1.in
+++ b/ovsdb/ovsdb-server.1.in
@@ -245,31 +245,210 @@ notifications (see below) to the request, it must be unique among all
active monitors. \fBovsdb\-server\fR rejects attempt to create two
monitors with the same identifier.
.
-.IP "4.1.12. Monitor2"
-A new monitor method added in Open vSwitch version 2.5. Monitor2 allows
-for more efficient update notifications (described below).
+.IP "4.1.12. Monitor_cond"
+A new monitor method added in Open vSwitch version 2.5. The monitor_cond
+request enables a client to replicate subsets of tables within an OVSDB
+database by requesting notifications of changes to rows matching one of
+the conditions specified in "where" by receiving the specified contents
+of these rows when table updates occur. Monitor_cond also allows a more
+efficient update notifications by receiving table-updates2 notifications
+(described below).
+.
.IP
-The monitor method described in Section 4.1.5 also applies to
-monitor2, with the following exceptions.
+The monitor method described in Section 4.1.5 also applies to monitor_cond,
+with the following exceptions:
.
.RS
.IP \(bu
-RPC request method becomes "monitor2".
+RPC request method becomes "monitor_cond".
.IP \(bu
-Replay result follows <table-updates2>, described in Section 4.1.13.
+Replay result follows <table-updates2>, described in Section 4.1.14.
.IP \(bu
Subsequent changes are sent to the client using the "update2" monitor
-notification, described in Section 4.1.13
+notification, described in Section 4.1.14
+.IP \(bu
+Update notifications are being sent only for rows matching [<conditions>*].
+<condition> is specified in Section 5.1 in the RFC with the following
+change: A condition can be either a 3-element JSON array as deescribed in
+the RFC or a boolean value. In case of an empty array an implicit true
+boolean value will be considered, and all rows will be monitored.
+.RE
+.
+.IP
+The request object has the following members:
+.
+.PP
+.RS
+.nf
+"method": "monitor_cond"
+"params": [<db-name>, <json-value>, <monitor-cond-requests>]
+"id": <nonnull-json-value>
+.fi
+.RE
+.
+.IP
+The <json-value> parameter is used to match subsequent update notifications
+(see below) to this request. The <monitor-cond-requests> object maps the name
+of the table to an array of <monitor-cond-request>.
+.
+.IP
+Each <monitor-cond-request> is an object with the following members:
+.
+.PP
+.RS
+.nf
+"columns": [<column>*] optional
+"where": [<condition>*] optional
+"select": <monitor-select> optional
+.fi
+.RE
+.
+.IP
+The "columns", if present, define the columns within the table to be monitored
+that match conditions. If not present all columns are being monitored.
+.
+.IP
+The "where" if present is a JSON array of <condition> and boolean values. If not
+present or condition is an empty array, implicit True will be considered and
+updates on all rows will be sent. <condition> is specified in Section 5.1 in
+the RFC with the following change: A condition can be either a 3-element JSON
+array as deescribed in the RFC or a boolean value. In case of an empty array an
+implicit true boolean value will be considered, and all rows will be monitored.
+.
+.IP
+<monitor-select> is an object with the following members:
+.
+.PP
+.RS
+.nf
+"initial": <boolean> optional
+"insert": <boolean> optional
+"delete": <boolean> optional
+"modify": <boolean> optional
+.fi
+.RE
+.
+.IP
+The contents of this object specify how the columns or table are to be
+monitored as explained in more detail below.
+.
+.IP
+The response object has the following members:
+.
+.PP
+.RS
+.nf
+"result": <table-updates2>
+"error": null
+"id": same "id" as request
+.fi
.RE
.
.IP
-Both monitor and monitor2 sessions can exist concurrently. However,
-monitor and monitor2 shares the same <json-value> parameter space; it
-must be unique among all monitor and monitor2 sessions.
+The <table-updates2> object is described in detail in Section 4.1.14. It
+contains the contents of the tables for which "initial" rows are selected.
+If no tables initial contents are requested, then "result" is an empty object.
+,
+.IP
+Subsequently, when changes to a specified table that match one of the conditions
+in monitor-cond-request are committed, the changes are automatically sent to the
+client using the "update2" monitor notification (see Section 4.1.14). This
+monitoring persists until the JSON-RPC session terminates or until the client
+sends a "monitor_cancel" JSON-RPC request.
+.
+.IP
+Each <monitor-cond-request> specifies one or more conditions and the manner in
+which the rows that match the conditions are to be monitored. The circumstances in
+which an "update" notification is sent for a row within the table are determined by
+<monitor-select>:
+.
+.RS
+.IP \(bu
+If "initial" is omitted or true, every row in the original table that matches one of
+the conditions is sent as part of the response to the "monitor_cond" request.
+.IP \(bu
+If "insert" is omitted or true, "update" notifications are sent for rows newly
+inserted into the table that match conditions or for rows modified in the table
+so that their old version does not match the condition and new version does.
+(new row in the client's replica table)
+.IP \(bu
+If "delete" is omitted or true, "update" notifications are sent for rows deleted
+from the table that match conditions or for rows modified in the table so that
+their old version does match the conditions and new version does not. (deleted row
+in the client's replica)
+.IP \(bu
+If "modify" is omitted or true, "update" notifications are sent whenever a row in
+the table that matches conditions in both old and new version is modified.
+.RE
+.
+.IP
+Both monitor and monitor_cond sessions can exist concurrently. However,
+monitor and monitor_cond shares the same <json-value> parameter space; it
+must be unique among all monitor and monitor_cond sessions.
+.
+.IP "4.1.13. Monitor_cond_change"
+The "monitor_cond_change" request enables a client to change an existing
+conditional replication of the database by specifying a new set of conditions
+for each replicated table.
+.
+.IP
+The request object has the following members:
+.
+.IP
+.RS
+.nf
+"method": "monitor_cond_change"
+"params": [<json-value>, <monitor-cond-change-requests>]
+"id": <nonnull-json-value>
+.fi
+.RE
+.
+.IP
+The <json-value> parameter should have a value of an existing conditional
+monitoring session from this client. The <monitor-cond-change-requests> object
+maps the name of the table to an array of <monitor-cond-change-request>.
+.
+.IP
+Each <monitor-cond-change-request> is an object with the following members:
+.
+.IP
+.RS
+.IP "added: [<condition>*]"
+new set of conditions to be added to the existing set of conditions for this
+table.
+.IP "removed: [<condition>*]"
+existing conditions to be removed from replication.
+.RE
+.
+.IP
+<condition> is specified in Section 5.1 in the RFC.
+.IP
+The response object has the following members:
+.
+.IP
+.RS
+.nf
+"result": <table-updates>
+"error": null
+"id": same "id" as request
+.fi
+.RE
+.IP
+The <table-updates> object is described in detail in Section 4.1.6 in the RFC.
+If insert contents are requested by origin monitor_cond request,
+<table-updates> will contain any newly matched rows by "added" conditions.
+If deleted contents are requested by origin monitor request, <table-updates>
+will contain any matched rows by "removed" conditions.
+.
+.IP
+Changes according to the new conditions are automatically sent to the client
+using the "update" monitor notification (see Section 4.1.6 in the RFC). In
+case that newly set of conditions is empty, no update notifications will be
+sent.
.
-.IP "4.1.13. Update2 notification"
+.IP "4.1.14. Update2 notification"
The "update2" notification is sent by the server to the client to report
-changes in tables that are being monitored following a "monitor2" request
+changes in tables that are being monitored following a "monitor_cond" request
as described above. The notification has the following members:
.
.RS
@@ -284,7 +463,8 @@ as described above. The notification has the following members:
The <json-value> in "params" is the same as the value passed as the
<json-value> in "params" for the corresponding "monitor" request.
<table-updates2> is an object that maps from a table name to a <table-update2>.
-A <table-update2> is an object that maps from row's UUID to a <row-update2> object. A <row-update2> is an object with one of the following members:
+A <table-update2> is an object that maps from row's UUID to a <row-update2>
+object. A <row-update2> is an object with one of the following members:
.
.RS
.IP "\(dqinitial\(dq: <row>"
@@ -326,8 +506,8 @@ elements, <row> includes the value from the new column.
.
.IP
Initial views of rows are not presented in update2 notifications,
-but in the response object to the monitor2 request. The formatting of the
-<table-updates2> object, however, is the same in either case.
+but in the response object to the monitor_cond request. The formatting
+of the <table-updates2> object, however, is the same in either case.
.
.IP "5.1. Notation"
For <condition>, RFC 7047 only allows the use of \fB!=\fR, \fB==\fR,
--
2.1.4
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