Fix get-sp-metadata sp-metadata file location

get-sp-metadata action hardcodes the location of an sp metadata file
which is incorrect - it should use the application name to allow custom
application names and usage of multiple keystone-saml-mellon
applications (to have multiple IdPs).

In order to make unit testing easier the global variable for the sp
metadata file in actions.py is moved into a function so that it is
evaluated at the function call time, not module import time.

Change-Id: Ia73cd633f2948080e9a892869074ed2775ecc33c
Closes-Bug: #1833202

src/actions/actions.py

@@ -18,10 +18,9 @@ import sys
 import charmhelpers.core.hookenv as hookenv
 
 
-SP_METADATA_FILE = "/etc/apache2/mellon/sp-meta.keystone-saml-mellon.xml"
-
-
 def get_sp_metadata(*args):
+    SP_METADATA_FILE = "/etc/apache2/mellon/sp-meta.{}.xml".format(
+        hookenv.service_name())
     if not os.path.exists(SP_METADATA_FILE):
         return hookenv.action_fail(
             "The SP metadata file {} does not exist"

tox.ini

@@ -36,6 +36,11 @@ basepython = python3.6
 deps = -r{toxinidir}/test-requirements.txt
 commands = stestr run {posargs}
 
+[testenv:py37]
+basepython = python3.7
+deps = -r{toxinidir}/test-requirements.txt
+commands = stestr run {posargs}
+
 [testenv:pep8]
 basepython = python3
 deps = -r{toxinidir}/test-requirements.txt

unit_tests/test_actions.py

@@ -28,6 +28,7 @@ class TestKeystoneSAMLMellonActions(test_utils.PatchHelper):
         super().setUp()
         self.patch_object(actions.hookenv, 'action_set')
         self.patch_object(actions.hookenv, 'action_fail')
+        self.patch_object(actions.hookenv, 'service_name')
         self.patch_object(actions, "os")
 
         self.patch(
@@ -38,6 +39,9 @@ class TestKeystoneSAMLMellonActions(test_utils.PatchHelper):
         self.open.return_value = self.fileobj
 
     def test_get_sp_metadata(self):
+        service_name = 'keystone-foobar-mellon'
+        self.service_name.return_value = service_name
+
         # Valid XML
         self.sp_metadata_xml = (
             "<?xml version='1.0' encoding='UTF-8'?>"
@@ -46,7 +50,8 @@ class TestKeystoneSAMLMellonActions(test_utils.PatchHelper):
             "</ds:X509Data> </ds:KeyInfo>")
         self.file.readlines.return_value = self.sp_metadata_xml
         self.metadata_file = ("/etc/apache2/mellon/"
-                              "sp-meta.keystone-saml-mellon.xml")
+                              "sp-meta.{}.xml".format(
+                                  service_name))
 
         # File Does not exist
         self.os.path.exists.return_value = False