Merge lp:~frankban/juju-deployer/fix-tags-constraint into lp:juju-deployer

[Francesco Banconi]

When deploying bundles, provide the tags constraint as a list rather than a string.
This fixes a problem reported by users, see http://pastebin.com/5McramHp

[Madison Scott-Clary (makyo)]

LGTM - thanks!

review: Approve (code)

[Tim Van Steenburgh (tvansteenburgh)]

LGTM.

review: Approve

=== modified file 'deployer/tests/test_constraints.py'
--- deployer/tests/test_constraints.py	2014-02-12 16:35:01 +0000
+++ deployer/tests/test_constraints.py	2015-09-03 14:28:00 +0000
@@ -113,10 +113,20 @@
 
     def test_non_numerics_are_not_converted(self):
         # Constraints that expect strings are not affected by the parsing.
-        keys = ['arch', 'container', 'tags']
+        keys = ['arch', 'container']
         for k in keys:
             value = {
                 k: '1T',
             }
             result = parse_constraints(value)
             self.assertEqual(result[k], '1T')
+
+    def test_tags(self):
+        # Tags are provided as a list of strings.
+        constraints = parse_constraints({'tags': 'foo,bar'})
+        self.assertEqual({'tags': ['foo', 'bar']}, constraints)
+
+    def test_single_tag(self):
+        # A single tag is converted to a list.
+        constraints = parse_constraints({'tags': 'foo'})
+        self.assertEqual({'tags': ['foo']}, constraints)

=== modified file 'deployer/utils.py'
--- deployer/utils.py	2015-03-16 22:25:44 +0000
+++ deployer/utils.py	2015-09-03 14:28:00 +0000
@@ -208,6 +208,7 @@
         return value
     constraints_with_units = ['mem', 'root-disk']
     numerics = ['cpu-cores', 'cpu-power'] + constraints_with_units
+    lists = ['tags']
     constraints = {}
     if isinstance(value, dict):
         constraints.update(value)
@@ -218,7 +219,12 @@
             constraints[k] = v
 
     for k, v in constraints.items():
-        if k in numerics:
+        if k in lists:
+            v = v.split(',')
+        elif k in numerics:
+            # Currently numeric constraints are never passed as slices. For
+            # this reason, it is safe to assume that a numeric value is always
+            # a string and never a list.
             units = 1
             if k in constraints_with_units:
                 v, units = _convert_units_specifier(v)
@@ -377,7 +383,7 @@
 def x_in_y(x, y):
     """Check to see if the second argument is named in the first
     argument's unit placement spec.
-    
+
     Both arguments provided are services with unit placement directives.
     If the first service appears in the second service's unit placement,
     either colocated on a default unit, colocated with a specific unit,