[virt-tools-list] [virt-manager] [PATCH v2 5/8] create: Call virt-bootstrap asynchronously

[Radostin Stoyanov]

Log messages from the virtBootstrap's logger are stored in string
buffer and shown in case of failure.

The bootstrap method is called at the end of the "create dialog" (when
"Finish" button is clicked).

For coordination we use global variable "self.container_bootstrap_flag"
Assigned values are:

1. "CT_BOOTSTRAP_NOT_STARTED" - Container bootstrap is not started.
        This is the initial value of the flag variable.
2. "CT_BOOTSTRAP_RUNNING" - Container bootstrap is running.
        This is when the bootstrap process has started and
	"_validate_final_page()" method should wait until the process
	finish. The validation method is called again from the
	finished callback of the asynchronous process.
3. OS tree path is used as value when the container bootstrap is
   finished successfully (no exception was thrown).
   Setting this value allows "_validate_final_page()" to return True
   and "_finish_clicked()" to proceed.
---
 virtManager/create.py | 113 +++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 112 insertions(+), 1 deletion(-)

diff --git a/virtManager/create.py b/virtManager/create.py
index 5007d77..f823ab7 100644
--- a/virtManager/create.py
+++ b/virtManager/create.py
@@ -21,6 +21,7 @@
 import logging
 import pkgutil
 import os
+import cStringIO
 import threading
 import time
 
@@ -68,6 +69,10 @@ DEFAULT_MEM = 1024
  OS_COL_IS_SHOW_ALL) = range(4)
 
 
+(CT_BOOTSTRAP_NOT_STARTED,
+ CT_BOOTSTRAP_RUNNING) = range(2)
+
+
 #####################
 # Pretty UI helpers #
 #####################
@@ -142,6 +147,8 @@ class vmmCreate(vmmGObjectUI):
         self._netlist = None
         self._mediacombo = None
 
+        self.container_bootstrap_flag = CT_BOOTSTRAP_NOT_STARTED
+
         self._addstorage = vmmAddStorage(self.conn, self.builder, self.topwin)
         self.widget("storage-align").add(self._addstorage.top_box)
         def _browse_file_cb(ignore, widget):
@@ -448,6 +455,7 @@ class vmmCreate(vmmGObjectUI):
         src_model = (self.widget("install-oscontainer-source-url-combo")
                          .get_model())
         _populate_media_model(src_model, self.config.get_container_urls())
+        self.container_bootstrap_flag = CT_BOOTSTRAP_NOT_STARTED
 
 
 
@@ -1993,7 +2001,9 @@ class vmmCreate(vmmGObjectUI):
             if not fs:
                 return self.err.val_err(_("An OS directory path is required."))
 
-            if self._get_config_oscontainer_bootstrap():
+            # If container bootstrap is enabled and was not perfromed yet
+            if (self._get_config_oscontainer_bootstrap()
+                and self.container_bootstrap_flag != fs):
 
                 src_url = self._get_config_oscontainer_source_url()
                 user = self._get_config_oscontainer_source_username()
@@ -2276,6 +2286,31 @@ class vmmCreate(vmmGObjectUI):
             _mark_vmm_device(nic)
             self._guest.add_device(nic)
 
+        container_bootstrap = self._get_config_oscontainer_bootstrap()
+        # If creating new container and "container bootstrap" is enabled
+        if self._guest.os.is_container() and container_bootstrap:
+            # Get destination path
+            dest = self.widget("install-oscontainer-fs").get_text()
+
+            if self.container_bootstrap_flag == CT_BOOTSTRAP_RUNNING:
+                return False  # Stop if container bootstrap is already running
+
+            # If the bootstrap was not yet performed on the current destination
+            # path.
+            # This check handles the case when container creations has failed
+            # after bootstrap and the user has changed the destination path.
+            elif self.container_bootstrap_flag != dest:
+                # Start container bootstrap
+                src_url = self._get_config_oscontainer_source_url()
+                user = self._get_config_oscontainer_source_username()
+                passwd = self._get_config_oscontainer_source_password()
+                insecure = self._get_config_oscontainer_isecure()
+
+                self._container_image_bootstrap(src_url, dest, user, passwd,
+                                                insecure)
+                # Wait for container bootstrap to complete
+                return False
+
         return True
 
 
@@ -2407,6 +2442,10 @@ class vmmCreate(vmmGObjectUI):
     ##########################
 
     def _finish_clicked(self, src_ignore):
+        # Stop if container bootstrap is running
+        if self.container_bootstrap_flag == CT_BOOTSTRAP_RUNNING:
+            return
+
         # Validate the final page
         page = self.widget("create-pages").get_current_page()
         if self._validate(page) is not True:
@@ -2583,3 +2622,75 @@ class vmmCreate(vmmGObjectUI):
             self.err.show_err(_("Error continue install: %s") % str(e))
 
         return True
+
+
+    def _create_directory_tree(self, asyncjob, src, dest, user, passwd, insecure):
+        """
+        Call bootstrap method from virtBootstrap.
+        """
+        try:
+            import virtBootstrap
+        except ImportError as err:
+            asyncjob.set_error("Please install virt-bootstrap", err)
+
+        # Use string buffer to store log messages
+        log_stream = cStringIO.StringIO()
+
+        # Get virt-bootstrap logger
+        vbLogger = logging.getLogger('virtBootstrap')
+        vbLogger.setLevel(logging.DEBUG)
+        vbLogger.addHandler(logging.StreamHandler(log_stream))
+
+        # Key word arguments to be passed
+        kwargs = {'uri': src, 'dest': dest, 'not_secure': insecure}
+        if user and passwd:
+            kwargs['username'] = user
+            kwargs['password'] = passwd
+
+        logging.debug('Start container bootstrap')
+        try:
+            virtBootstrap.bootstrap(**kwargs)
+            # Set the flag value to destination to indicate success
+            self.container_bootstrap_flag = dest
+        except Exception as err:
+            asyncjob.set_error(err, log_stream.getvalue())
+        except:
+            asyncjob.set_error("Container bootstrap has failed",
+                               log_stream.getvalue())
+
+
+    def _container_image_bootstrap(self, src, dest, user, passwd, insecure):
+        """
+        Launch virt-bootstrap as async job
+        """
+
+        params = [src, dest, user, passwd, insecure]
+
+        logging.debug("Start asynchronous job to bootstrap container.")
+        # Set flag to running
+        self.container_bootstrap_flag = CT_BOOTSTRAP_RUNNING
+        parentobj = self._customize_window or self
+        progWin = vmmAsyncJob(self._create_directory_tree, params,
+                              self._container_bootstrap_finished_cb,
+                              [parentobj],
+                              _("Bootstrap Container"),
+                              _("The process of download and untar the "
+                                "container image may take a few minutes "
+                                "to complete."),
+                              parentobj.topwin)
+        progWin.run()
+
+
+    def _container_bootstrap_finished_cb(self, error, details, parentobj):
+        """
+        Thread callback - See self._container_image_bootstrap()
+        """
+
+        if error:
+            error = (_("Unable to complete container bootstrap: %s") % error)
+            parentobj.err.show_err(error, details=details)
+            # Reset flag
+            self.container_bootstrap_flag = CT_BOOTSTRAP_NOT_STARTED
+        else:
+            # Proceed with domain creation
+            self._finish_clicked(None)
-- 
2.9.4