Support log tail/save for instance

Support to show log content and save instance log files:

  openstack database log tail [--lines LINES] <instance> <log_name>
  openstack database log save [--file FILE] <instance> <log_name>

Change-Id: I2a4eecca663f9126f770fae4c4be28b3667f91c4

5 files changed, 125 insertions, 21 deletions

diff --git a/releasenotes/notes/ussuri-02-instance-log-tail-save-0b267a761faa11ea.yaml b/releasenotes/notes/ussuri-02-instance-log-tail-save-0b267a761faa11ea.yaml
new file mode 100644
index 0000000..5516d14
--- /dev/null
+++ b/releasenotes/notes/ussuri-02-instance-log-tail-save-0b267a761faa11ea.yaml
@@ -0,0 +1,9 @@
+---
+features:
+  - |
+    Support to show log content and save instance log files:
+
+    .. code-block:: console
+
+        openstack database log tail [--lines LINES] <instance> <log_name>
+        openstack database log save [--file FILE] <instance> <log_name>
diff --git a/setup.cfg b/setup.cfg
index 57c55bc..a6a35a8 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -81,6 +81,8 @@ openstack.database.v1 =
     database_log_list = troveclient.osc.v1.database_logs:ListDatabaseLogs
     database_log_set = troveclient.osc.v1.database_logs:SetDatabaseInstanceLog
     database_log_show = troveclient.osc.v1.database_logs:ShowDatabaseInstanceLog
+    database_log_tail = troveclient.osc.v1.database_logs:ShowDatabaseInstanceLogContents
+    database_log_save = troveclient.osc.v1.database_logs:SaveDatabaseInstanceLog
     database_quota_show = troveclient.osc.v1.database_quota:ShowDatabaseQuota
     database_quota_update = troveclient.osc.v1.database_quota:UpdateDatabaseQuota
     database_root_disable = troveclient.osc.v1.database_root:DisableDatabaseRoot
diff --git a/troveclient/osc/v1/database_logs.py b/troveclient/osc/v1/database_logs.py
index eb342c3..d43d331 100644
--- a/troveclient/osc/v1/database_logs.py
+++ b/troveclient/osc/v1/database_logs.py
@@ -10,12 +10,13 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-"""Database v1 Logs action implementations"""
+from __future__ import print_function
 
 from osc_lib.command import command
 from osc_lib import utils as osc_utils
 import six
 
+from troveclient import exceptions
 from troveclient.i18n import _
 
 
@@ -134,3 +135,97 @@ class ShowDatabaseInstanceLog(command.ShowOne):
         result = log_info._info
 
         return zip(*sorted(six.iteritems(result)))
+
+
+class ShowDatabaseInstanceLogContents(command.Command):
+    _description = _("Show the content of log file.")
+
+    def get_parser(self, prog_name):
+        parser = super(ShowDatabaseInstanceLogContents, self).get_parser(
+            prog_name)
+        parser.add_argument(
+            'instance',
+            metavar='<instance>',
+            type=str,
+            help=_('Id or Name of the instance.')
+        )
+        parser.add_argument(
+            'log_name',
+            metavar='<log_name>',
+            type=str,
+            help=_('Name of log to operate.')
+        )
+        parser.add_argument(
+            '--lines', default=50, type=int,
+            help="The number of log lines can be shown in batch.",
+        )
+
+        return parser
+
+    def take_action(self, parsed_args):
+        db_instances = self.app.client_manager.database.instances
+        instance = osc_utils.find_resource(db_instances,
+                                           parsed_args.instance)
+
+        try:
+            log_gen = db_instances.log_generator(instance,
+                                                 parsed_args.log_name,
+                                                 lines=parsed_args.lines)
+            for log_part in log_gen():
+                print(log_part, end="")
+        except exceptions.GuestLogNotFoundError:
+            print(
+                "ERROR: No published '%(log_name)s' log was found for "
+                "%(instance)s" % {'log_name': parsed_args.log_name,
+                                  'instance': instance}
+            )
+        except Exception as ex:
+            error_msg = ex.message.split('\n')
+            print(error_msg[0])
+
+
+class SaveDatabaseInstanceLog(command.Command):
+    _description = _("Save the log file.")
+
+    def get_parser(self, prog_name):
+        parser = super(SaveDatabaseInstanceLog, self).get_parser(prog_name)
+        parser.add_argument(
+            'instance',
+            metavar='<instance>',
+            type=str,
+            help=_('Id or Name of the instance.')
+        )
+        parser.add_argument(
+            'log_name',
+            metavar='<log_name>',
+            type=str,
+            help=_('Name of log to operate.')
+        )
+        parser.add_argument(
+            '--file',
+            help="Path of file to save log to for instance.",
+        )
+
+        return parser
+
+    def take_action(self, parsed_args):
+        db_instances = self.app.client_manager.database.instances
+        instance = osc_utils.find_resource(db_instances,
+                                           parsed_args.instance)
+
+        try:
+            filepath = db_instances.log_save(instance,
+                                             parsed_args.log_name,
+                                             filename=parsed_args.file)
+            print(_('Log "%(log_name)s" written to %(file_name)s')
+                  % {'log_name': parsed_args.log_name,
+                     'file_name': filepath})
+        except exceptions.GuestLogNotFoundError:
+            print(
+                "ERROR: No published '%(log_name)s' log was found for "
+                "%(instance)s" % {'log_name': parsed_args.log_name,
+                                  'instance': instance}
+            )
+        except Exception as ex:
+            error_msg = ex.message.split('\n')
+            print(error_msg[0])
diff --git a/troveclient/v1/instances.py b/troveclient/v1/instances.py
index a122bc3..15725a3 100644
--- a/troveclient/v1/instances.py
+++ b/troveclient/v1/instances.py
@@ -412,9 +412,9 @@ class Instances(base.ManagerWithFind):
         common.check_for_exceptions(resp, body, url)
         return DatastoreLog(self, body['log'], loaded=True)
 
-    def _get_container_info(self, instance, log_name, publish):
+    def _get_container_info(self, instance, log_name):
         try:
-            log_info = self.log_action(instance, log_name, publish=publish)
+            log_info = self.log_show(instance, log_name)
             container = log_info.container
             prefix = log_info.prefix
             metadata_file = log_info.metafile
@@ -424,33 +424,33 @@ class Instances(base.ManagerWithFind):
                 raise exceptions.GuestLogNotFoundError()
             raise
 
-    def log_generator(self, instance, log_name, publish=None, lines=50,
-                      swift=None):
+    def log_generator(self, instance, log_name, lines=50, swift=None):
         """Return generator to yield the last <lines> lines of guest log.
 
         :param instance: The :class:`Instance` (or its ID) of the database
                          instance to get the log for.
         :param log_name: The name of <log> to publish
-        :param publish: Publish updates before displaying log
         :param lines: Display last <lines> lines of log (0 for all lines)
         :param swift: Connection to swift
         :rtype: generator function to yield log as chunks.
         """
-
         if not swift:
             swift = self._get_swift_client()
 
-        def _log_generator(instance, log_name, publish, lines, swift):
+        def _log_generator(instance, log_name, lines, swift):
             try:
                 container, prefix, metadata_file = self._get_container_info(
-                    instance, log_name, publish)
+                    instance, log_name)
+
                 head, body = swift.get_container(container, prefix=prefix)
                 log_obj_to_display = []
+
                 if lines:
                     total_lines = lines
                     partial_results = False
                     parts = sorted(body, key=lambda obj: obj['last_modified'],
                                    reverse=True)
+
                     for part in parts:
                         obj_hdrs = swift.head_object(container, part['name'])
                         obj_lines = int(obj_hdrs['x-object-meta-lines'])
@@ -461,13 +461,16 @@ class Instances(base.ManagerWithFind):
                         lines -= obj_lines
                     if not partial_results:
                         lines = total_lines
+
                     part = log_obj_to_display.pop(0)
                     hdrs, log_obj = swift.get_object(container, part['name'])
                     log_by_lines = log_obj.decode().splitlines()
                     yield "\n".join(log_by_lines[-1 * lines:]) + "\n"
                 else:
+                    # Show all the logs
                     log_obj_to_display = sorted(
                         body, key=lambda obj: obj['last_modified'])
+
                 for log_part in log_obj_to_display:
                     headers, log_obj = swift.get_object(container,
                                                         log_part['name'])
@@ -477,20 +480,19 @@ class Instances(base.ManagerWithFind):
                     raise exceptions.GuestLogNotFoundError()
                 raise
 
-        return lambda: _log_generator(instance, log_name, publish,
-                                      lines, swift)
+        return lambda: _log_generator(instance, log_name, lines, swift)
 
-    def log_save(self, instance, log_name, publish=None, filename=None):
+    def log_save(self, instance, log_name, filename=None):
         """Saves a guest log to a file.
 
         :param instance: The :class:`Instance` (or its ID) of the database
                          instance to get the log for.
         :param log_name: The name of <log> to publish
-        :param publish: Publish updates before displaying log
         :rtype: Filename to which log was saved
         """
-        written_file = filename or (instance.name + '-' + log_name + ".log")
-        log_gen = self.log_generator(instance, log_name, publish, 0)
+        written_file = filename or (
+            'trove-' + instance.id + '-' + log_name + ".log")
+        log_gen = self.log_generator(instance, log_name, lines=0)
         with open(written_file, 'w') as f:
             for log_obj in log_gen():
                 f.write(log_obj)
diff --git a/troveclient/v1/shell.py b/troveclient/v1/shell.py
index bb6f2f6..1b72d31 100644
--- a/troveclient/v1/shell.py
+++ b/troveclient/v1/shell.py
@@ -2292,8 +2292,6 @@ def do_log_discard(cs, args):
 @utils.arg('instance', metavar='<instance>',
            help=_('Id or Name of the instance.'))
 @utils.arg('log_name', metavar='<log_name>', help=_('Name of log to publish.'))
-@utils.arg('--publish', action='store_true', default=False,
-           help=_('Publish latest entries from guest before display.'))
 @utils.arg('--lines', metavar='<lines>', default=50, type=int,
            help=_('Publish latest entries from guest before display.'))
 @utils.service_type('database')
@@ -2302,7 +2300,7 @@ def do_log_tail(cs, args):
     try:
         instance = _find_instance(cs, args.instance)
         log_gen = cs.instances.log_generator(instance, args.log_name,
-                                             args.publish, args.lines)
+                                             args.lines)
         for log_part in log_gen():
             print(log_part, end="")
     except exceptions.GuestLogNotFoundError:
@@ -2316,8 +2314,6 @@ def do_log_tail(cs, args):
 @utils.arg('instance', metavar='<instance>',
            help=_('Id or Name of the instance.'))
 @utils.arg('log_name', metavar='<log_name>', help=_('Name of log to publish.'))
-@utils.arg('--publish', action='store_true', default=False,
-           help=_('Publish latest entries from guest before display.'))
 @utils.arg('--file', metavar='<file>', default=None,
            help=_('Path of file to save log to for instance.'))
 @utils.service_type('database')
@@ -2326,7 +2322,7 @@ def do_log_save(cs, args):
     try:
         instance = _find_instance(cs, args.instance)
         filename = cs.instances.log_save(instance, args.log_name,
-                                         args.publish, args.file)
+                                         filename=args.file)
         print(_('Log "%(log_name)s" written to %(file_name)s')
               % {'log_name': args.log_name,
                  'file_name': filename})