docs: conventions for test layouts

Signed-off-by: Alfredo Deza <adeza@redhat.com>

diff --git a/docs/source/testing/layout.rst b/docs/source/testing/layout.rst
index 7f7d7874d92f98f42d9755da4a59edda35c87670..0f4155b45cc8d28161310c145ecd1f4dba17b151 100644 (file)
--- a/docs/source/testing/layout.rst
+++ b/docs/source/testing/layout.rst
@@ -32,6 +32,22 @@ At the very least, a scenario will need these files:
 
 Conventions
 -----------
+Python test files (unlike scenarios) rely on paths to *map* where they belong. For
+example, a file that should only test monitor nodes would live in
+``ceph-ansible/tests/functional/tests/mon/``. Internally, the test runner
+(``py.test``) will *mark* these as tests that should run on a monitor only.
+Since the configuration of a scenario already defines what node has a given
+role, then it is easier for the system to only run tests that belong to
+a particular node type.
+
+The current convention is a bit manual, with initial path support for:
+
+* mon
+* osd
+* mds
+* rgw
+* journal_collocation
+* all/any (if none of the above are matched, then these are run on any host)
 
 
 .. _testinfra: