system update: test with two image recipes

With OSTree it is fairly easy to build original and update in
different image recipes. This makes it easier to debug the test,
because both build directories are preserved. It might also speed up
running the tests repeatedly, because the rootfs should be reusable.

TODO: in practice, we still need to rebuild. Check why.

The base infrastructure could be used to test switching between
different images with OSTree.

Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>

Author: pohly

meta-refkit-core/lib/oeqa/selftest/cases/refkit_ostree.py

@@ -17,7 +17,9 @@ class RefkitOSTreeUpdateBase(SystemUpdateBase):
     # We test the normal refkit-image-common with
     # OSTree system update enabled.
     IMAGE_PN = 'refkit-image-common'
+    IMAGE_PN_UPDATE = IMAGE_PN
     IMAGE_BBAPPEND = 'refkit-image-common.bbappend'
+    IMAGE_BBAPPEND_UPDATE = IMAGE_BBAPPEND
     IMAGE_CONFIG = '''
 IMAGE_FEATURES_append = " ostree"
 '''
@@ -146,3 +148,28 @@ def test(self):
 
 class RefkitOSTreeUpdateTestIndividual(RefkitOSTreeUpdateBase, metaclass=RefkitOSTreeUpdateMeta):
     pass
+
+class RefkitOSTreeUpdateTestDev(RefkitOSTreeUpdateTestAll, metaclass=RefkitOSTreeUpdateMeta):
+    """
+    This class avoids rootfs rebuilding by using two separate image
+    recipes. It's using slight tricks like overriding the OSTREE_BRANCH,
+    so the other tests are more realistic. Use this one when debugging problems.
+    """
+
+    IMAGE_PN = 'refkit-image-update-test-a'
+    IMAGE_PN_UPDATE = 'refkit-image-update-test-b'
+    IMAGE_BBAPPEND = 'refkit-image-update-test-a.bbappend'
+    IMAGE_BBAPPEND_UPDATE = 'refkit-image-update-test-b.bbappend'
+
+    def setUpLocal(self):
+        super().setUpLocal()
+        def create_image_bb(pn):
+            bb = pn + '.bb'
+            self.track_for_cleanup(bb)
+            self.append_config('BBFILES_append = " %s"' % os.path.abspath(bb))
+            with open(bb, 'w') as f:
+                f.write('require ${META_REFKIT_CORE_BASE}/recipes-images/images/refkit-image-common.bb\n')
+                f.write('OSTREE_BRANCHNAME = "${DISTRO}/${MACHINE}/%s"\n' % self.IMAGE_PN)
+                f.write('''IMAGE_FEATURES_append = "${@ bb.utils.filter('DISTRO_FEATURES', 'stateless', d)}"\n''')
+        create_image_bb(self.IMAGE_PN)
+        create_image_bb(self.IMAGE_PN_UPDATE)

meta-refkit-core/lib/oeqa/selftest/systemupdate/systemupdatebase.py

@@ -220,12 +220,18 @@ class SystemUpdateBase(OESelftestTestCase):
     # The image that will get built, booted and updated.
     IMAGE_PN = 'core-image-minimal'
 
-    # The .bbappend name which matches IMAGE_PN.
+    # The image used for preparing the update. Usually
+    # the same, but some update mechanisms may also
+    # support switching between images.
+    IMAGE_PN_UPDATE = IMAGE_PN
+
+    # The .bbappend name which matches IMAGE_PN resp. IMAGE_PN_UPDATE.
     # For example, OSTree might build and boot "core-image-minimal-ostree",
     # but the actual image recipe is "core-image-minimal" and thus
     # we would need "core-image-minimal.bbappend". Also allows to handle
     # cases where the bbappend file name must have a wildcard.
     IMAGE_BBAPPEND = 'core-image-minimal.bbappend'
+    IMAGE_BBAPPEND_UPDATE = IMAGE_BBAPPEND
 
     # Additional image settings that will get written into the IMAGE_BBAPPEND.
     IMAGE_CONFIG = ''
@@ -271,8 +277,10 @@ def create_image_bbappend(is_update):
             applied also to image variants.
             """
 
-            self.track_for_cleanup(self.IMAGE_BBAPPEND)
-            with open(self.IMAGE_BBAPPEND, 'w') as f:
+            bbappend = self.IMAGE_BBAPPEND_UPDATE if is_update else self.IMAGE_BBAPPEND
+            self.append_config('BBFILES_append = " %s"' % os.path.abspath(bbappend))
+            self.track_for_cleanup(bbappend)
+            with open(bbappend, 'w') as f:
                 f.write('''
 python system_update_test_modify () {
     import base64
@@ -295,7 +303,7 @@ def create_image_bbappend(is_update):
        self.IMAGE_MODIFY.modify_image_build(testname, updates, is_update)))
 
         # Creating a .bbappend for the image will trigger a rebuild.
-        self.write_config('BBFILES_append = " %s"' % os.path.abspath(self.IMAGE_BBAPPEND))
+        # To avoid this, use separate image recipes.
         create_image_bbappend(False)
         self.logger.info('Building base image')
         result = bitbake(self.IMAGE_PN, output_log=self.logger)
@@ -307,12 +315,6 @@ def create_image_bbappend(is_update):
         # self.track_for_cleanup(self.image_dir_test)
         oe.path.copyhardlinktree(self.image_dir, self.image_dir_test)
 
-        # Now we change our .bbappend so that the updated state is generated
-        # during the next rebuild.
-        create_image_bbappend(True)
-        self.logger.info('Building updated image')
-        bitbake(self.IMAGE_PN, output_log=self.logger)
-
         # Change DEPLOY_DIR_IMAGE so that we use our copy of the
         # images from before the update. Further customizations for booting can
         # be done by rewriting self.image_dir_test/IMAGE_PN-MACHINE.qemuboot.conf
@@ -323,6 +325,13 @@ def create_image_bbappend(is_update):
         # Boot image, verify before and after update.
         with self.boot_image(overrides) as qemu:
             self.verify_image(testname, False, qemu, updates)
+
+            # Now we change our .bbappend so that the updated state is generated
+            # during the next rebuild.
+            create_image_bbappend(True)
+            self.logger.info('Building updated image')
+            bitbake(self.IMAGE_PN_UPDATE, output_log=self.logger)
+
             reboot = self.update_image(qemu)
             if not reboot:
                 self.verify_image(testname, True, qemu, updates)