deploy: Always cleanup deploy tempdir on failure

When a configuration extension or write extension fails, then it should
abort then, not continue to run other configuration extensions.

There was a period where this didn't happen, due to a missing feature
of cliapp that was assumed to be there, so failure to run these
extensions was not noticed.

This has since been fixed, but this would cause deploy to fail to
clean up its temporary directories.

Now it will cleanup the contents of the temporary directory after
any failures after it has been created.

A small amount of re-ordering was performed to make this easier.

1 files changed, 52 insertions, 45 deletions

diff --git a/morphlib/plugins/deploy_plugin.py b/morphlib/plugins/deploy_plugin.py
index 092441ec..8530cb57 100644
--- a/morphlib/plugins/deploy_plugin.py
+++ b/morphlib/plugins/deploy_plugin.py
@@ -283,58 +283,65 @@ class DeployPlugin(cliapp.Plugin):
         if push:
             self.other.delete_remote_build_refs(build_repos)
             
-        # Unpack the artifact (tarball) to a temporary directory.
-        self.app.status(msg='Unpacking system for configuration')
 
+        # Create a tempdir for this deployment to work in
         deploy_tempdir = tempfile.mkdtemp(
             dir=os.path.join(self.app.settings['tempdir'], 'deployments'))
-        system_tree = tempfile.mkdtemp(dir=deploy_tempdir)
-
-        if build_command.lac.has(artifact):
-            f = build_command.lac.get(artifact)
-        elif build_command.rac.has(artifact):
-            f = build_command.rac.get(artifact)
-        else:
-            raise cliapp.AppException('Deployment failed as system is not yet'
-                                      ' built.\nPlease ensure system is built'
-                                      ' before deployment.')
-        tf = tarfile.open(fileobj=f)
-        tf.extractall(path=system_tree)
-        
-        self.app.status(
-            msg='System unpacked at %(system_tree)s',
-            system_tree=system_tree)
-
-        # Extensions get a private tempdir so we can more easily clean
-        # up any files an extension left behind
-        deploy_private_tempdir = tempfile.mkdtemp(dir=deploy_tempdir)
-        env['TMPDIR'] = deploy_private_tempdir
-
-        # Run configuration extensions.
-        self.app.status(msg='Configure system')
-        names = artifact.source.morphology['configuration-extensions']
-        for name in names:
+        try:
+            # Create a tempdir to extract the rootfs in
+            system_tree = tempfile.mkdtemp(dir=deploy_tempdir)
+
+            # Extensions get a private tempdir so we can more easily clean
+            # up any files an extension left behind
+            deploy_private_tempdir = tempfile.mkdtemp(dir=deploy_tempdir)
+            env['TMPDIR'] = deploy_private_tempdir
+
+            # Unpack the artifact (tarball) to a temporary directory.
+            self.app.status(msg='Unpacking system for configuration')
+
+            if build_command.lac.has(artifact):
+                f = build_command.lac.get(artifact)
+            elif build_command.rac.has(artifact):
+                f = build_command.rac.get(artifact)
+            else:
+                raise cliapp.AppException('Deployment failed as system is'
+                                          ' not yet built.\nPlease ensure'
+                                          ' the system is built before'
+                                          ' deployment.')
+            tf = tarfile.open(fileobj=f)
+            tf.extractall(path=system_tree)
+
+            self.app.status(
+                msg='System unpacked at %(system_tree)s',
+                system_tree=system_tree)
+
+
+            # Run configuration extensions.
+            self.app.status(msg='Configure system')
+            names = artifact.source.morphology['configuration-extensions']
+            for name in names:
+                self._run_extension(
+                    root_repo_dir,
+                    build_ref,
+                    name,
+                    '.configure',
+                    [system_tree],
+                    env)
+
+            # Run write extension.
+            self.app.status(msg='Writing to device')
             self._run_extension(
                 root_repo_dir,
                 build_ref,
-                name,
-                '.configure',
-                [system_tree],
+                deployment_type,
+                '.write',
+                [system_tree, location],
                 env)
-        
-        # Run write extension.
-        self.app.status(msg='Writing to device')
-        self._run_extension(
-            root_repo_dir,
-            build_ref,
-            deployment_type,
-            '.write',
-            [system_tree, location],
-            env)
-        
-        # Cleanup.
-        self.app.status(msg='Cleaning up')
-        shutil.rmtree(deploy_tempdir)
+
+        finally:
+            # Cleanup.
+            self.app.status(msg='Cleaning up')
+            shutil.rmtree(deploy_tempdir)
 
         self.app.status(msg='Finished deployment')