Tags, measurements and boot scripts

[ibaldin]

Added the ability to

1. Set tags on any element (node, link, service, component or interface). Tags are lists of strings of length under 255. They are immutable.

   # assuming n1 is a Node
   n1.tags = f.Tags('blue', 'heavy')
   # tags are immutable but iterable
   self.assertTrue('blue' in n1.tags)
   # unset the tags
   n1.tags = None
   self.assertEqual(n1.tags, None)

2. Set measurement framework data on any element (node, link, service, component or interface). mf_data is a JSON-friendly object representing measurement configuration (combination of dicts, lists). You can set it directly to the .mf_data field of e.g. a VM. If the object is not JSON friendly or serializes into a string longer than 1M, you will get a MeasurementDataError exception:

       # for most uses, just set the object
       my_meas_data_object = {'key1': {'key2': ['some', 'config', 'info']}}
       n1.mf_data = my_meas_data_object
   
       # you get back your object (in this case a dict)
       self.assertTrue(isinstance(n1.mf_data, dict))
       mf_object2 = n1.mf_data
       self.assertTrue(mf_object2['key1'] == {'key2': ['some', 'config', 'info']})
   
       class MyClass:
           def __init__(self, val):
               self.val = val
   
       # this is not a valid object - json.dumps() will fail on it
       bad_meas_data_object = {'key1': MyClass(3)}
       with self.assertRaises(MeasurementDataError):
           n1.mf_data = bad_meas_data_object
   
       # most settable properties can be unset by setting them to None 
       n1.mf_data = None
       self.assertIsNone(n1.mf_data)

3. Set boot script on Node elements

       #boot script on nodes only
       n1.boot_script = """
       #!/bin/bash
   
       echo *
       """
       self.assertTrue("bash" in n1.boot_script)
       n1.boot_script = None
       self.assertIsNone(n1.boot_script)

[kthare10]

Looks good!