Merge lp:~ack/landscape-client/container-info-from-run-container-type into lp:~landscape/landscape-client/trunk

[Alberto Donato]

This changes container detection to use /run/container_type (which is created by /etc/init/container-detect.conf if running in a container).

This changes container detection to use /run/container_type (which is created by /etc/init/container-detect.conf if running in a container). The file contains a single line with the container type.

This fixes the issue with the current LXC detection on Saucy and supports other types of containers too (openvz, vserver, ...).

[Free Ekanayaka (free.ekanayaka)]

Looks good, +1!

review: Approve

[Geoff Teale (tealeg)]

+1, I don't like the one-line if style, but it's pythonic, so I'll get over it ;-)

review: Approve

=== modified file 'landscape/lib/tests/test_vm_info.py'
--- landscape/lib/tests/test_vm_info.py	2013-10-09 07:50:54 +0000
+++ landscape/lib/tests/test_vm_info.py	2013-10-14 09:45:01 +0000
@@ -127,34 +127,16 @@
 
 class GetContainerInfoTest(LandscapeTest):
 
-    def setUp(self):
-        super(GetContainerInfoTest, self).setUp()
-        self.root_path = self.makeDir()
-        self.proc_path = self.makeDir(
-            path=os.path.join(self.root_path, "proc"))
-
-    def make_cgroup(self, content):
-        """Create /sys/class/dmi/id/sys_vendor with the specified content."""
-        init_proc_path = os.path.join(self.proc_path, "1")
-        self.makeDir(path=init_proc_path)
-        self.makeFile(
-            dirname=init_proc_path, basename="cgroup", content=content)
-
-    def test_no_cgroup_file(self):
-        """If the cgroup file doesn't exist, it's not an LXC."""
-        self.assertEqual("", get_container_info(root_path=self.root_path))
-
-    def test_cgroup_not_in_lxc(self):
-        """
-        If the cgroup file exists, but there is no mention of LXC, it's not an
-        LXC.
-        """
-        self.make_cgroup("2:cpu:/")
-        self.assertEqual("", get_container_info(root_path=self.root_path))
-
-    def test_in_lxc(self):
-        """
-        If the cgroup file exists, and the group name is LXC, it's not an LXC.
-        """
-        self.make_cgroup("2:cpu:/lxc/test")
-        self.assertEqual("lxc", get_container_info(root_path=self.root_path))
+    def test_no_container(self):
+        """If not running in a container, an empty string is returned."""
+        self.assertEqual("", get_container_info(path="/does/not/exist"))
+
+    def test_in_container(self):
+        """If running in a container, the container type is returned."""
+        path = self.makeFile(content="lxc")
+        self.assertEqual("lxc", get_container_info(path=path))
+
+    def test_strip_newline(self):
+        """The container type doesn't contain newlines."""
+        path = self.makeFile(content="lxc\n")
+        self.assertEqual("lxc", get_container_info(path=path))

=== modified file 'landscape/lib/vm_info.py'
--- landscape/lib/vm_info.py	2013-10-09 07:50:54 +0000
+++ landscape/lib/vm_info.py	2013-10-14 09:45:01 +0000
@@ -50,15 +50,9 @@
     return ""
 
 
-def get_container_info(root_path="/"):
-    """
-    Return a string with the type of container the client is running in if it's
-    known, an empty string otherwise.
-    """
-    cgroup_file = os.path.join(root_path, "proc/1/cgroup")
-    if os.path.exists(cgroup_file):
-        for line in read_file(cgroup_file).splitlines():
-            tokens = line.split(":")
-            if tokens[-1].startswith("/lxc/"):
-                return "lxc"
-    return ""
+def get_container_info(path="/run/container_type"):
+    """
+    Return a string with the type of container the client is running in, if
+    any, an empty string otherwise.
+    """
+    return read_file(path).strip() if os.path.exists(path) else ""