Support download

Add support for downloading software changes and plugins
Default download directory is /tmp/<session_id>
Download url with filename including 'workflow' or 'actions'
are automatically extracted to /tmp/<session_id>/<workflow|actions>
Plugins will be used straight from those directories is Fenix
did not have a plugin with the same name.
Download directory and content will be automatically removed
when session is deleted by the admin

story: 2004147
Task: #27620

Change-Id: Ia1cce13d268da1888f5d8f02d39099b3c113fb86
Signed-off-by: Tomi Juvonen <tomi.juvonen@nokia.com>

fenix/workflow/workflow.py

@@ -23,6 +23,7 @@ from threading import Thread
 import time
 
 from fenix.db import api as db_api
+from fenix.utils.download import url_to_filename
 from fenix.utils.identity_auth import get_identity_auth
 from fenix.utils.identity_auth import get_session
 
@@ -50,6 +51,11 @@ class BaseWorkflow(Thread):
             self.actions = self._init_action_plugins(data["actions"])
         else:
             self.actions = []
+        if "download" in data:
+            self.downloads = self._init_downloads(data["download"])
+        else:
+            self.downloads = []
+
         self.projects = []
         self.instances = []
         self.proj_instance_actions = {}
@@ -98,6 +104,21 @@ class BaseWorkflow(Thread):
         else:
             return data
 
+    def _init_downloads(self, download_urls):
+        downloads = []
+        session_dir = "%s/%s" % (self.conf.engine.local_cache_dir,
+                                 self.session_id)
+        for url in download_urls:
+            LOG.info('%s: Download %s' % (self.session_id, url))
+            local_file = url_to_filename(session_dir, url)
+            if local_file is None:
+                raise Exception("cannot make filename from: %s " % url)
+            ddict = {
+                'session_id': self.session_id,
+                'local_file': local_file}
+            downloads.append(ddict)
+        return db_api.create_downloads(downloads)
+
     def _init_session(self, data):
         session = {
             'session_id': self.session_id,

fenix/workflow/workflows/default.py

@@ -14,11 +14,26 @@
 #    under the License.
 import datetime
 from importlib import import_module
+try:
+    from importlib.machinery import SourceFileLoader
+
+    def mod_loader_action_instance(mname, mpath, session_instance,
+                                   ap_db_instance):
+        mi = SourceFileLoader(mname, mpath).load_module()
+        return mi.ActionPlugin(session_instance, ap_db_instance)
+except ImportError:
+    from imp import load_source
+
+    def mod_loader_action_instance(mname, mpath, session_instance,
+                                   ap_db_instance):
+        mi = load_source(mname, mpath)
+        return mi.ActionPlugin(session_instance, ap_db_instance)
 
 from novaclient import API_MAX_VERSION as nova_max_version
 import novaclient.client as novaclient
 from novaclient.exceptions import BadRequest
 
+import os
 from oslo_log import log as logging
 import time
 
@@ -642,6 +657,9 @@ class Workflow(BaseWorkflow):
 
     def maintenance_by_plugin_type(self, hostname, plugin_type):
         aps = self.get_action_plugins_by_type(plugin_type)
+        session_dir = "%s/%s" % (self.conf.engine.local_cache_dir,
+                                 self.session_id)
+        download_plugin_dir = session_dir + "/actions/"
         if aps:
             LOG.info("%s: Calling action plug-ins with type %s" %
                      (self.session_id, plugin_type))
@@ -649,10 +667,27 @@ class Workflow(BaseWorkflow):
                 ap_name = "fenix.workflow.actions.%s" % ap.plugin
                 LOG.info("%s: Calling action plug-in module: %s" %
                          (self.session_id, ap_name))
-                action_plugin = getattr(import_module(ap_name), 'ActionPlugin')
                 ap_db_instance = self._create_action_plugin_instance(ap.plugin,
                                                                      hostname)
-                ap_instance = action_plugin(self, ap_db_instance)
+                try:
+                    action_plugin = getattr(import_module(ap_name),
+                                            'ActionPlugin')
+                    ap_instance = action_plugin(self, ap_db_instance)
+                except ImportError:
+                    download_plugin_file = "%s/%s.py" % (download_plugin_dir,
+                                                         ap.plugin)
+                    LOG.info("%s: Trying from: %s" % (self.session_id,
+                                                      download_plugin_file))
+                    if os.path.isfile(download_plugin_file):
+                        ap_instance = (
+                            mod_loader_action_instance(ap_name,
+                                                       download_plugin_file,
+                                                       self,
+                                                       ap_db_instance))
+                    else:
+                        raise Exception('%s: could not find action plugin %s' %
+                                        (self.session_id, ap.plugin))
+
                 ap_instance.run()
                 if ap_db_instance.state:
                     LOG.info('%s: %s finished with %s host %s' %