ovsdb: Add unixctl commands for OVSDB replication

Set and get the server to replicate from:

    ovsdb-server/set-remote-ovsdb-server {server}
    ovsdb-server/get-remote-ovsdb-server

Set and get the replicated table blacklist:

    ovsdb-server/set-sync-excluded-tables {DB:table,...}
    ovsdb-server/get-sync-excluded-tables

Connect to the configured server and start replication:

    ovsdb-server/connect-remote-ovsdb-server

Disconnect from the remote server and stop replication, without dropping
the replicated data:

    ovsdb-server/disconnect-remote-ovsdb-server

Signed-off-by: Mario Cabrera <mario.cabrera@hpe.com>
Signed-off-by: Andy Zhou <azhou@ovn.org>
Acked-by: Andy Zhou <azhou@ovn.org>

4 files changed, 133 insertions, 1 deletions

diff --git a/ovsdb/ovsdb-server.1.in b/ovsdb/ovsdb-server.1.in
index 37ec68da3..1d932c0be 100644
--- a/ovsdb/ovsdb-server.1.in
+++ b/ovsdb/ovsdb-server.1.in
@@ -188,6 +188,27 @@ again (with \fBovsdb\-server/add\-db\fR).
 Outputs a list of the currently configured databases added either through
 the command line or through the \fBovsdb\-server/add\-db\fR command.
 .
+.IP "\fBovsdb\-server/set\-remote\-ovsdb\-server \fIserver"
+Sets  the remote \fIserver\fR from which \fBovsdb\-server\fR connects through
+\fBovsdb\-server/connect\-remote\-ovsdb\-server\fR.
+.
+.IP "\fBovsdb\-server/get\-remote\-ovsdb\-server"
+Gets the remote server from which \fBovsdb\-server\fR is currently synchronizing
+its databases.
+.
+.IP "\fBovsdb\-server/connect\-remote\-ovsdb\-server"
+Causes \fBovsdb\-server\fR to synchronize its databases with the server
+specified by \fBovsdb\-server/set\-remote\-ovsdb\-server\fR.
+.
+.IP "\fBovsdb\-server/disconnect\-remote\-ovsdb\-server"
+Causes \fBovsdb\-server\fR to  stop  synchronizing  its  databases with a remote server.
+.
+.IP "\fBovsdb\-server/set\-sync\-excluded\-tables \fIdb\fB:\fItable\fR[\fB,\fIdb\fB:\fItable\fR]..."
+Sets the \fItable\fR whitin \fIdb\fR that will be excluded from synchronization.
+.
+.IP "\fBovsdb\-server/get\-sync\-excluded\-tables"
+Gets  the  tables  that are currently excluded from synchronization.
+.
 .so lib/vlog-unixctl.man
 .so lib/memory-unixctl.man
 .so lib/coverage-unixctl.man
diff --git a/ovsdb/ovsdb-server.c b/ovsdb/ovsdb-server.c
index 6fb0b2a01..11801188d 100644
--- a/ovsdb/ovsdb-server.c
+++ b/ovsdb/ovsdb-server.c
@@ -77,6 +77,12 @@ static unixctl_cb_func ovsdb_server_reconnect;
 static unixctl_cb_func ovsdb_server_perf_counters_clear;
 static unixctl_cb_func ovsdb_server_perf_counters_show;
 static unixctl_cb_func ovsdb_server_disable_monitor_cond;
+static unixctl_cb_func ovsdb_server_set_remote_ovsdb_server;
+static unixctl_cb_func ovsdb_server_get_remote_ovsdb_server;
+static unixctl_cb_func ovsdb_server_connect_remote_ovsdb_server;
+static unixctl_cb_func ovsdb_server_disconnect_remote_ovsdb_server;
+static unixctl_cb_func ovsdb_server_set_sync_excluded_tables;
+static unixctl_cb_func ovsdb_server_get_sync_excluded_tables;
 
 struct server_config {
     struct sset *remotes;
@@ -334,6 +340,19 @@ main(int argc, char *argv[])
     unixctl_command_register("ovsdb-server/perf-counters-clear", "", 0, 0,
                              ovsdb_server_perf_counters_clear, NULL);
 
+    unixctl_command_register("ovsdb-server/set-remote-ovsdb-server", "", 0, 1,
+                              ovsdb_server_set_remote_ovsdb_server, NULL);
+    unixctl_command_register("ovsdb-server/get-remote-ovsdb-server", "", 0, 0,
+                              ovsdb_server_get_remote_ovsdb_server, NULL);
+    unixctl_command_register("ovsdb-server/connect-remote-ovsdb-server", "", 0, 0,
+                              ovsdb_server_connect_remote_ovsdb_server, NULL);
+    unixctl_command_register("ovsdb-server/disconnect-remote-ovsdb-server", "", 0, 0,
+                              ovsdb_server_disconnect_remote_ovsdb_server, NULL);
+    unixctl_command_register("ovsdb-server/set-sync-excluded-tables", "", 0, 1,
+                              ovsdb_server_set_sync_excluded_tables, NULL);
+    unixctl_command_register("ovsdb-server/get-sync-excluded-tables", "", 0, 0,
+                              ovsdb_server_get_sync_excluded_tables, NULL);
+
     /* Simulate the behavior of OVS release prior to version 2.5 that
      * does not support the monitor_cond method.  */
     unixctl_command_register("ovsdb-server/disable-monitor-cond", "", 0, 0,
@@ -1019,6 +1038,84 @@ report_error_if_changed(char *error, char **last_errorp)
 }
 
 static void
+ovsdb_server_set_remote_ovsdb_server(struct unixctl_conn *conn,
+                                     int argc OVS_UNUSED, const char *argv[],
+                                     void *arg_ OVS_UNUSED)
+{
+    set_remote_ovsdb_server(argv[1]);
+    connect_to_remote_server = false;
+    unixctl_command_reply(conn, NULL);
+}
+
+static void
+ovsdb_server_get_remote_ovsdb_server(struct unixctl_conn *conn,
+                                     int argc OVS_UNUSED,
+                                     const char *argv[] OVS_UNUSED,
+                                     void *arg_ OVS_UNUSED)
+{
+    struct ds s;
+    ds_init(&s);
+
+    ds_put_format(&s, "%s\n", get_remote_ovsdb_server());
+
+    unixctl_command_reply(conn, ds_cstr(&s));
+    ds_destroy(&s);
+}
+
+static void
+ovsdb_server_connect_remote_ovsdb_server(struct unixctl_conn *conn,
+                                         int argc OVS_UNUSED,
+                                         const char *argv[] OVS_UNUSED,
+                                         void *arg_ OVS_UNUSED)
+{
+    if (!connect_to_remote_server) {
+        replication_init();
+        connect_to_remote_server = true;
+    }
+    unixctl_command_reply(conn, NULL);
+}
+
+static void
+ovsdb_server_disconnect_remote_ovsdb_server(struct unixctl_conn *conn,
+                                            int argc OVS_UNUSED,
+                                            const char *argv[] OVS_UNUSED,
+                                            void *arg_ OVS_UNUSED)
+{
+    disconnect_remote_server();
+    connect_to_remote_server = false;
+    unixctl_command_reply(conn, NULL);
+}
+
+static void
+ovsdb_server_set_sync_excluded_tables(struct unixctl_conn *conn,
+                                      int argc OVS_UNUSED,
+                                      const char *argv[],
+                                      void *arg_ OVS_UNUSED)
+{
+    set_tables_blacklist(argv[1]);
+    unixctl_command_reply(conn, NULL);
+}
+
+static void
+ovsdb_server_get_sync_excluded_tables(struct unixctl_conn *conn,
+                                 int argc OVS_UNUSED,
+                                 const char *argv[] OVS_UNUSED,
+                                 void *arg_ OVS_UNUSED)
+{
+    struct ds s;
+    const char *table_name;
+    struct sset table_blacklist = get_tables_blacklist();
+
+    ds_init(&s);
+
+    SSET_FOR_EACH(table_name, &table_blacklist) {
+        ds_put_format(&s, "%s\n", table_name);
+    }
+
+    unixctl_command_reply(conn, ds_cstr(&s));
+}
+
+static void
 ovsdb_server_exit(struct unixctl_conn *conn, int argc OVS_UNUSED,
                   const char *argv[] OVS_UNUSED,
                   void *exiting_)
diff --git a/ovsdb/replication.c b/ovsdb/replication.c
index f734ae2ac..736771461 100644
--- a/ovsdb/replication.c
+++ b/ovsdb/replication.c
@@ -38,7 +38,6 @@ 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_);
@@ -118,6 +117,12 @@ set_remote_ovsdb_server(const char *remote_server)
     remote_ovsdb_server = nullable_xstrdup(remote_server);
 }
 
+const char *
+get_remote_ovsdb_server(void)
+{
+    return remote_ovsdb_server;
+}
+
 void
 set_tables_blacklist(const char *blacklist)
 {
@@ -127,6 +132,12 @@ set_tables_blacklist(const char *blacklist)
     }
 }
 
+struct sset
+get_tables_blacklist(void)
+{
+    return tables_blacklist;
+}
+
 void
 disconnect_remote_server(void)
 {
diff --git a/ovsdb/replication.h b/ovsdb/replication.h
index 74acdbaa5..012ca0960 100644
--- a/ovsdb/replication.h
+++ b/ovsdb/replication.h
@@ -30,9 +30,12 @@ struct db {
     struct ovsdb_txn *txn;
 };
 
+void replication_init(void);
 void replication_run(struct shash *dbs);
 void set_remote_ovsdb_server(const char *remote_server);
+const char *get_remote_ovsdb_server(void);
 void set_tables_blacklist(const char *blacklist);
+struct sset get_tables_blacklist(void);
 void disconnect_remote_server(void);
 const struct db *find_db(const struct shash *all_dbs, const char *db_name);
 void replication_usage(void);