kvm: NDB server instance is OK even if no image is uploaded

NBD server is not running until an image is uploaded. Make sure that the
promise doesn't fail until the image is there. Also display a WARNING in
the connection parameter to say that the NBD server is not running.

software/kvm/buildout.hash.cfg

@@ -47,7 +47,7 @@ md5sum = b617d64de73de1eed518185f310bbc82
 
 [template-nbd]
 filename = instance-nbd.cfg.in
-md5sum = c3667c9bbaa8627dad90f1abd62d2f16
+md5sum = 70267d09442a7e5a048ebdf06217e21e
 
 [template-ansible-promise]
 filename = template/ansible-promise.in

software/kvm/instance-nbd.cfg.in

@@ -15,6 +15,7 @@ offline = true
 
 [rootdirectory]
 recipe = slapos.cookbook:mkdirectory
+bin = $${buildout:directory}/bin
 etc = $${buildout:directory}/etc
 srv = $${buildout:directory}/srv
 log = $${buildout:directory}/log
@@ -34,12 +35,18 @@ shell-path = ${dash:location}/bin/dash
 # XXX TODO: Wait for the iso to be uploaded (execute_wait)
 path = $${basedirectory:services}/nbdserver
 
+[nbd-checker-bin]
+recipe = slapos.recipe.template:jinja2
+template = inline:#!/bin/sh
+  [ ! -f $${onetimeupload-instance:image-path} ] ||
+    $${buildout:executable} -c 'import socket ; socket.create_connection(("$${nbd-instance:ip}","$${nbd-instance:port}")).close()'
+rendered = $${rootdirectory:bin}/check-nbd-running.sh
+
 [nbd-promise]
 <= monitor-promise-base
-module = check_port_listening
+module = check_command_execute
 name = nbd_promise.py
-config-hostname = $${nbd-instance:ip}
-config-port = $${nbd-instance:port}
+config-command = $${nbd-checker-bin:rendered}
 
 [gen-passwd]
 recipe = slapos.cookbook:generate.password
@@ -66,6 +73,13 @@ config-port = $${onetimeupload-instance:port}
 
 [publish-connection-information]
 recipe = slapos.cookbook:publish
-nbd_url = nbd://[$${nbd-instance:ip}]:$${nbd-instance:port}
-upload_url = http://[$${onetimeupload-instance:ip}]:$${onetimeupload-instance:port}/
+nbd_hostname = $${nbd-instance:ip}
+nbd_port = $${nbd-instance:port}
+upload_url = http://[$${onetimeupload-instance:ip}]:$${onetimeupload-instance:port}
 upload_key = $${onetimeupload-instance:key}
+status_message = $${detect-if-cdrom-present:status}
+
+[detect-if-cdrom-present]
+recipe = collective.recipe.shelloutput
+commands =
+  status = [ -f $${onetimeupload-instance:image-path} ] && echo "image already uploaded, you can't upload it again" || echo "WARNING: no image yet, the NBD server doesn't work"

software/kvm/test/test.py

@@ -308,3 +308,23 @@ class TestInstanceResilient(InstanceTestCase):
         'takeover-kvm-1-password',
         'takeover-kvm-1-url',
         'url']))
+
+class TestInstanceNbdServer(InstanceTestCase):
+  __partition_reference__ = 'ins'
+  instance_max_retry = 5
+
+  @classmethod
+  def getInstanceSoftwareType(cls):
+    return 'nbd'
+
+  def test(self):
+    connection_parameter_dict = self.computer_partition\
+      .getConnectionParameterDict()
+    self.assertNotIn("WARNING", connection_parameter_dict['upload_url'])
+    result = requests.get(connection_parameter_dict['upload_url'].strip(), verify=False)
+    self.assertEqual(
+      httplib.OK,
+      result.status_code
+    )
+    self.assertTrue('<title>Upload new File</title>' in result.text)
+    self.assertIn("WARNING", connection_parameter_dict['nbd_url'])