[ovs-dev] [PATCH v3] Introduce ovs-appctl command to monitor HVs sb connection status

[Jakub Sitnicki]

On Tue, 31 Jul 2018 15:22:38 +0200
Lorenzo Bianconi <lorenzo.bianconi at redhat.com> wrote:

> Add 'connection-status' command to ovs-appctl utility in order to check
> if a given chassis is currently connected to SB db
> 
> Acked-by: Mark Michelson <mmichels at redhat.com>
> Co-authored-by: aginwala <aginwala at ebay.com>
> Signed-off-by: aginwala <aginwala at ebay.com>
> Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi at redhat.com>
> ---
> Changes since v2:
> - check idl->session pointer in ovsdb_idl_is_connected routine
> 
> Changes since v1:
> - add unit tests for ovs-appctl -t ovn-controller connection-status
>   command
> - use jsonrpc_session_is_connected() in ovsdb_idl_is_connected routine
> ---
>  lib/ovsdb-idl.c                     |  6 +++++
>  lib/ovsdb-idl.h                     |  1 +
>  ovn/controller/ovn-controller.8.xml |  5 +++++
>  ovn/controller/ovn-controller.c     | 17 +++++++++++++++
>  tests/ovn-controller.at             | 34 +++++++++++++++++++++++++++++
>  5 files changed, 63 insertions(+)
> 
> diff --git a/lib/ovsdb-idl.c b/lib/ovsdb-idl.c
> index ae0a55c3a..40c29cbd1 100644
> --- a/lib/ovsdb-idl.c
> +++ b/lib/ovsdb-idl.c
> @@ -922,6 +922,12 @@ ovsdb_idl_is_alive(const struct ovsdb_idl *idl)
>             idl->state != IDL_S_ERROR;
>  }
>  
> +bool
> +ovsdb_idl_is_connected(const struct ovsdb_idl *idl)
> +{
> +    return idl->session && jsonrpc_session_is_connected(idl->session);
> +}
> +
>  /* Returns the last error reported on a connection by 'idl'.  The return value
>   * is 0 only if no connection made by 'idl' has ever encountered an error and
>   * a negative response to a schema request has never been received. See
> diff --git a/lib/ovsdb-idl.h b/lib/ovsdb-idl.h
> index ea18b22f5..5f933b628 100644
> --- a/lib/ovsdb-idl.h
> +++ b/lib/ovsdb-idl.h
> @@ -80,6 +80,7 @@ void ovsdb_idl_force_reconnect(struct ovsdb_idl *);
>  void ovsdb_idl_verify_write_only(struct ovsdb_idl *);
>  
>  bool ovsdb_idl_is_alive(const struct ovsdb_idl *);
> +bool ovsdb_idl_is_connected(const struct ovsdb_idl *idl);
>  int ovsdb_idl_get_last_error(const struct ovsdb_idl *);
>  
>  void ovsdb_idl_set_probe_interval(const struct ovsdb_idl *, int probe_interval);
> diff --git a/ovn/controller/ovn-controller.8.xml b/ovn/controller/ovn-controller.8.xml
> index 2e4e53d6b..8035638b3 100644
> --- a/ovn/controller/ovn-controller.8.xml
> +++ b/ovn/controller/ovn-controller.8.xml
> @@ -398,6 +398,11 @@
>          0x800</code>.
>        </p>
>        </dd>
> +
> +      <dt><code>connection-status</code></dt>
> +      <dd>
> +        Show OVN SBDB connection status for the chassis.
> +      </dd>
>        </dl>
>      </p>
>  
> diff --git a/ovn/controller/ovn-controller.c b/ovn/controller/ovn-controller.c
> index 470e02ae8..bc4e8014b 100644
> --- a/ovn/controller/ovn-controller.c
> +++ b/ovn/controller/ovn-controller.c
> @@ -68,6 +68,7 @@ static unixctl_cb_func ct_zone_list;
>  static unixctl_cb_func meter_table_list;
>  static unixctl_cb_func group_table_list;
>  static unixctl_cb_func inject_pkt;
> +static unixctl_cb_func ovn_controller_conn_show;
>  
>  #define DEFAULT_BRIDGE_NAME "br-int"
>  #define DEFAULT_PROBE_INTERVAL_MSEC 5000
> @@ -594,6 +595,9 @@ main(int argc, char *argv[])
>          ovsdb_idl_create(ovnsb_remote, &sbrec_idl_class, true, true));
>      ovsdb_idl_set_leader_only(ovnsb_idl_loop.idl, false);
>  
> +    unixctl_command_register("connection-status", "", 0, 0,
> +                             ovn_controller_conn_show, ovnsb_idl_loop.idl);
> +
>      struct ovsdb_idl_index *sbrec_chassis_by_name
>          = chassis_index_create(ovnsb_idl_loop.idl);
>      struct ovsdb_idl_index *sbrec_multicast_group_by_name_datapath
> @@ -1122,3 +1126,16 @@ update_probe_interval(const struct ovsrec_open_vswitch_table *ovs_table,
>  
>      ovsdb_idl_set_probe_interval(ovnsb_idl, interval);
>  }
> +
> +static void
> +ovn_controller_conn_show(struct unixctl_conn *conn, int argc OVS_UNUSED,
> +                         const char *argv[] OVS_UNUSED, void *idl_)
> +{
> +    char *result = "not connected";
> +    struct ovsdb_idl *idl = idl_;

'result' definitely should be pointing to const data. 'idl' could be
declared as const as well.

> +
> +    if (idl && ovsdb_idl_is_connected(idl)) {

It doesn't look like 'idl' can be null or we would be in trouble in
other code paths.

Sorry I didn't notice these the first time.

-Jakub

> +       result = "connected";
> +    }
> +    unixctl_command_reply(conn, result);
> +}
> diff --git a/tests/ovn-controller.at b/tests/ovn-controller.at
> index ecc6a50da..13e88a0cc 100644
> --- a/tests/ovn-controller.at
> +++ b/tests/ovn-controller.at
> @@ -228,3 +228,37 @@ as ovn-sb
>  OVS_APP_EXIT_AND_WAIT([ovsdb-server])
>  
>  AT_CLEANUP
> +
> +# Check ovn-controller connection status to Southbound database
> +AT_SETUP([ovn-controller - check sbdb connection])
> +AT_KEYWORDS([ovn])
> +ovn_init_db ovn-sb
> +
> +net_add n1
> +sim_add hv
> +as hv
> +ovs-vsctl \
> +    -- add-br br-phys \
> +    -- add-br br-eth0 \
> +    -- add-br br-eth1 \
> +    -- add-br br-eth2
> +ovn_attach n1 br-phys 192.168.0.1
> +
> +check_sbdb_connection () {
> +    test "$(ovs-appctl -t ovn-controller connection-status)" = "$1"
> +}
> +
> +OVS_WAIT_UNTIL([check_sbdb_connection connected])
> +
> +ovs-vsctl set open . external_ids:ovn-remote=tcp:192.168.0.10:6642
> +OVS_WAIT_UNTIL([check_sbdb_connection 'not connected'])
> +
> +# reset the remote for clean-up
> +ovs-vsctl set open . external_ids:ovn-remote=unix:$ovs_base/ovn-sb/ovn-sb.sock
> +# Gracefully terminate daemons
> +OVN_CLEANUP_SBOX([hv])
> +OVN_CLEANUP_VSWITCH([main])
> +as ovn-sb
> +OVS_APP_EXIT_AND_WAIT([ovsdb-server])
> +
> +AT_CLEANUP