ovsdb: Add table exclusion functionality to OVSDB replication

A blacklist of tables that will be excluded from replication can be
specified by the following option:

--sync-exclude-tables=db:table[,db:table]…

Where 'table' corresponds to a table name, and 'db' corresponds to the
database name where the table resides.

Signed-off-by: Mario Cabrera <mario.cabrera@hpe.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>

3 files changed, 53 insertions, 3 deletions

diff --git a/ovsdb/ovsdb-server.c b/ovsdb/ovsdb-server.c
index 650c164ac..1b9de19c9 100644
--- a/ovsdb/ovsdb-server.c
+++ b/ovsdb/ovsdb-server.c
@@ -1266,6 +1266,7 @@ parse_options(int *argcp, char **argvp[],
         OPT_BOOTSTRAP_CA_CERT,
         OPT_PEER_CA_CERT,
         OPT_SYNC_FROM,
+        OPT_SYNC_EXCLUDE,
         VLOG_OPTION_ENUMS,
         DAEMON_OPTION_ENUMS
     };
@@ -1285,6 +1286,7 @@ parse_options(int *argcp, char **argvp[],
         {"certificate", required_argument, NULL, 'c'},
         {"ca-cert",     required_argument, NULL, 'C'},
         {"sync-from",   required_argument, NULL, OPT_SYNC_FROM},
+        {"sync-exclude-tables", required_argument, NULL, OPT_SYNC_EXCLUDE},
         {NULL, 0, NULL, 0},
     };
     char *short_options = ovs_cmdl_long_options_to_short_options(long_options);
@@ -1350,6 +1352,10 @@ parse_options(int *argcp, char **argvp[],
             connect_to_remote_server = true;
             break;
 
+        case OPT_SYNC_EXCLUDE:
+            set_tables_blacklist(optarg);
+            break;
+
         case '?':
             exit(EXIT_FAILURE);
 
diff --git a/ovsdb/replication.c b/ovsdb/replication.c
index 669f4758c..1fa0f253a 100644
--- a/ovsdb/replication.c
+++ b/ovsdb/replication.c
@@ -35,8 +35,10 @@
 static char *remote_ovsdb_server;
 static struct jsonrpc *rpc;
 static struct sset monitored_tables = SSET_INITIALIZER(&monitored_tables);
+static struct sset tables_blacklist = SSET_INITIALIZER(&tables_blacklist);
 static bool reset_dbs = true;
 
+void replication_init(void);
 static struct jsonrpc *open_jsonrpc(const char *server);
 static struct ovsdb_error *check_jsonrpc_error(int error,
                                                struct jsonrpc_msg **reply_);
@@ -73,6 +75,14 @@ static struct ovsdb_error *execute_update(struct ovsdb_txn *txn,
                                           struct json *new);
 
 void
+replication_init(void)
+{
+    sset_init(&monitored_tables);
+    sset_init(&tables_blacklist);
+    reset_dbs = true;
+}
+
+void
 replication_run(struct shash *all_dbs)
 {
     if (sset_is_empty(&monitored_tables) && remote_ovsdb_server) {
@@ -109,10 +119,30 @@ set_remote_ovsdb_server(const char *remote_server)
 }
 
 void
+set_tables_blacklist(const char *blacklist)
+{
+    char *save_ptr = NULL;
+    char *blacklist_item;
+
+    replication_init();
+
+    if (blacklist) {
+        char *t_blacklist = xstrdup(blacklist);
+        for (blacklist_item = strtok_r(t_blacklist, ",", &save_ptr);
+             blacklist_item != NULL;
+             blacklist_item = strtok_r(NULL, ",", &save_ptr)) {
+            sset_add(&tables_blacklist, blacklist_item);
+        }
+        free(t_blacklist);
+    }
+}
+
+void
 disconnect_remote_server(void)
 {
     jsonrpc_close(rpc);
     sset_destroy(&monitored_tables);
+    sset_destroy(&tables_blacklist);
 
     if (remote_ovsdb_server) {
         free(remote_ovsdb_server);
@@ -160,9 +190,15 @@ reset_database(struct ovsdb *db, struct ovsdb_txn *txn)
         struct ovsdb_table *table = table_node->data;
         struct ovsdb_row *row;
 
-        HMAP_FOR_EACH (row, hmap_node, &table->rows) {
-            ovsdb_txn_row_delete(txn, row);
+        /* Do not reset if table is blacklisted. */
+        char *blacklist_item = xasprintf(
+            "%s%s%s", db->schema->name, ":", table_node->name);
+        if (!sset_contains(&tables_blacklist, blacklist_item)) {
+            HMAP_FOR_EACH (row, hmap_node, &table->rows) {
+                ovsdb_txn_row_delete(txn, row);
+            }
         }
+        free(blacklist_item);
     }
 }
 
@@ -293,7 +329,14 @@ send_monitor_requests(struct shash *all_dbs)
 
                 for (int j = 0; j < n; j++) {
                     struct ovsdb_table_schema *table = nodes[j]->data;
-                    add_monitored_table(table, monitor_request);
+
+                    /* Check if table is not blacklisted. */
+                    char *blacklist_item = xasprintf(
+                        "%s%s%s", db_name, ":", table->name);
+                    if (!sset_contains(&tables_blacklist, blacklist_item)) {
+                        add_monitored_table(table, monitor_request);
+                    }
+                    free(blacklist_item);
                 }
                 free(nodes);
 
diff --git a/ovsdb/replication.h b/ovsdb/replication.h
index f9b7d6323..74acdbaa5 100644
--- a/ovsdb/replication.h
+++ b/ovsdb/replication.h
@@ -32,6 +32,7 @@ struct db {
 
 void replication_run(struct shash *dbs);
 void set_remote_ovsdb_server(const char *remote_server);
+void set_tables_blacklist(const char *blacklist);
 void disconnect_remote_server(void);
 const struct db *find_db(const struct shash *all_dbs, const char *db_name);
 void replication_usage(void);