integration test: initial commit of integration test framework

The adds in end-to-end testing of cloud-init. The framework utilizes
LXD and cloud images as a backend to test user-data passed in.
Arbitrary data is then captured from predefined commands specified
by the user. After collection, data verification is completed by
running a series of Python unit tests against the collected data.

Currently only the Ubuntu Trusty, Xenial, Yakkety, and Zesty
releases are supported. Test cases for 50% of the modules is
complete and available.

Additionally a Read the Docs file was created to guide test
writing and execution.

1 files changed, 120 insertions, 0 deletions

diff --git a/tests/cloud_tests/instances/base.py b/tests/cloud_tests/instances/base.py
new file mode 100644
index 00000000..9559d286
--- /dev/null
+++ b/tests/cloud_tests/instances/base.py
@@ -0,0 +1,120 @@
+# This file is part of cloud-init. See LICENSE file for license information.
+
+import os
+import uuid
+
+
+class Instance(object):
+    """
+    Base instance object
+    """
+    platform_name = None
+
+    def __init__(self, name):
+        """
+        setup
+        """
+        self.name = name
+
+    def execute(self, command, stdin=None, stdout=None, stderr=None, env={}):
+        """
+        command: the command to execute as root inside the image
+        stdin, stderr, stdout: file handles
+        env: environment variables
+
+        Execute assumes functional networking and execution as root with the
+        target filesystem being available at /.
+
+        return_value: tuple containing stdout data, stderr data, exit code
+        """
+        raise NotImplementedError
+
+    def read_data(self, remote_path, encode=False):
+        """
+        read_data from instance filesystem
+        remote_path: path in instance
+        decode: return as string
+        return_value: data as str or bytes
+        """
+        raise NotImplementedError
+
+    def write_data(self, remote_path, data):
+        """
+        write data to instance filesystem
+        remote_path: path in instance
+        data: data to write, either str or bytes
+        """
+        raise NotImplementedError
+
+    def pull_file(self, remote_path, local_path):
+        """
+        copy file at 'remote_path', from instance to 'local_path'
+        """
+        with open(local_path, 'wb') as fp:
+            fp.write(self.read_data(remote_path), encode=True)
+
+    def push_file(self, local_path, remote_path):
+        """
+        copy file at 'local_path' to instance at 'remote_path'
+        """
+        with open(local_path, 'rb') as fp:
+            self.write_data(remote_path, fp.read())
+
+    def run_script(self, script):
+        """
+        run script in target and return stdout
+        """
+        script_path = os.path.join('/tmp', str(uuid.uuid1()))
+        self.write_data(script_path, script)
+        (out, err, exit_code) = self.execute(['/bin/bash', script_path])
+        return out
+
+    def console_log(self):
+        """
+        return_value: bytes of this instance’s console
+        """
+        raise NotImplementedError
+
+    def reboot(self, wait=True):
+        """
+        reboot instance
+        """
+        raise NotImplementedError
+
+    def shutdown(self, wait=True):
+        """
+        shutdown instance
+        """
+        raise NotImplementedError
+
+    def start(self, wait=True):
+        """
+        start instance
+        """
+        raise NotImplementedError
+
+    def destroy(self):
+        """
+        clean up instance
+        """
+        pass
+
+    def _wait_for_cloud_init(self, wait_time):
+        """
+        wait until system has fully booted and cloud-init has finished
+        """
+        if not wait_time:
+            return
+
+        found_msg = 'found'
+        cmd = ('for ((i=0;i<{wait};i++)); do [ -f "{file}" ] && '
+               '{{ echo "{msg}";break; }} || sleep 1; done').format(
+            file='/run/cloud-init/result.json',
+            wait=wait_time, msg=found_msg)
+
+        (out, err, exit) = self.execute(['/bin/bash', '-c', cmd])
+        if out.strip() != found_msg:
+            raise OSError('timeout: after {}s, cloud-init has not started'
+                          .format(wait_time))
+
+# vi: ts=4 expandtab