lovely.testlayers 0.1.0a2

Testing Layers for use with zope.testing

Test layers with working directories

There is a mixin class that provides usefull methods to generate a working directory and make snapshots thereof.

>>> from lovely.testlayers.layer import WorkDirectoryLayer

Let us create a sample layer.

>>> class MyLayer(WorkDirectoryLayer):
...     def __init__(self, name):
...         self.__name__ = name

>>> myLayer = MyLayer('mylayer')

To initialize the directories we need to create the directory structure.

>>> myLayer.setUpWD()

We can get relative paths by using the os.path join syntax.

>>> myLayer.wdPath('a', 'b')
'.../__builtin__.MyLayer.mylayer/work/a/b'

Let us create a directory.

>>> import os
>>> os.mkdir(myLayer.wdPath('firstDirectory'))

And make a snapshot.

>>> myLayer.makeSnapshot('first')

We can check if we have a snapshot.

>>> myLayer.hasSnapshot('first')
True

And now we make a second directory and another snapshot.

>>> os.mkdir(myLayer.wdPath('secondDirectory'))
>>> myLayer.makeSnapshot('second')

We now have 2 directories.

>>> sorted(os.listdir(myLayer.wdPath()))
['firstDirectory', 'secondDirectory']

We now restore the “first” snapshot

>>> myLayer.restoreSnapshot('first')
>>> sorted(os.listdir(myLayer.wdPath()))
['firstDirectory']

We can also restore the “second” snapshot.

>>> myLayer.restoreSnapshot('second')
>>> sorted(os.listdir(myLayer.wdPath()))
['firstDirectory', 'secondDirectory']

We can also override snapshots.

>>> os.mkdir(myLayer.wdPath('thirdDirectory'))
>>> myLayer.makeSnapshot('first')
>>> myLayer.restoreSnapshot('first')
>>> sorted(os.listdir(myLayer.wdPath()))
['firstDirectory', 'secondDirectory', 'thirdDirectory']

memcached test layer

This layer starts and stops a memcached daemon on given port (default is 11222)

>>> from lovely.testlayers import memcached

>>> ml = memcached.MemcachedLayer('ml')

So let us setup the server.

>>> ml.setUp()

Now we can acces memcached on port 11222.

>>> import telnetlib
>>> tn =  telnetlib.Telnet('localhost', 11222)
>>> tn.close()

No more after teardown.

>>> ml.tearDown()
>>> tn =  telnetlib.Telnet('localhost', 11222)
Traceback (most recent call last):
...
error:...Connection refused...

Cassandra test layer

This layer starts and stops a cassandra instance with a given storage configuration template. For information about cassandra see: http://en.wikipedia.org/wiki/Cassandra_(database)

>>> from lovely.testlayers import cass

An example template exists in this directory which we now use for this example.

>>> import os
>>> storage_conf_tmpl = os.path.join(os.path.dirname(__file__),
...                                  'storage-conf.xml.in')

The following keys are provided when the template gets evaluated. Let us look them up in the example file.

>>> import re
>>> tmpl_pat = re.compile(r'.*\%\(([^ \)]+)\)s.*')
>>> conf_keys = set()
>>> for l in file(storage_conf_tmpl).readlines():
...     m = tmpl_pat.match(l)
...     if m:
...         conf_keys.add(m.group(1))

>>> sorted(conf_keys)
['control_port', 'storage_port', 'thrift_port', 'var']

With the storage configuration path we can instantiate a new cassandra layer. The thrift_port, storage_port, and control_port are optional keyword arguments for the constructor and default to the standard port +10000.

>>> l = cass.CassandraLayer('l', storage_conf=storage_conf_tmpl)
>>> l.thrift_port
19160

So let us setup the server.

>>> l.setUp()

Now the cassandra server is up and running. We test this by connecting to the thrift port via telnet.

>>> import telnetlib
>>> tn = telnetlib.Telnet('localhost', l.thrift_port)
>>> tn.close()

The connection is refused after teardown.

>>> l.tearDown()

>>> telnetlib.Telnet('localhost', l.thrift_port)
Traceback (most recent call last):
...
error:...Connection refused