z3c.recipe.mkdir 0.6

``z3c.recipe.mkdir`` README
***************************

This package provides a ``zc.buildout`` recipe used to generate directories
within a buildout.

Please see ``docs/index.rst`` for detailed documentation.


:mod:`z3c.recipe.mkdir` Usage
=============================


Recipe Options
--------------

``z3c.recipe.mkdir`` provides the following options:

* ``paths``
Contains the path(s) of directories created in normalized,
absolute form. I.e.::

mydir/../foo/bar

becomes::

/path/to/buildout-dir/foo/bar

* ``remove-on-update``
Default: ``no``

By default, created directories are not removed
on updates of buildout configuration. This is a security measure
as created directories might contain valuable data.

You can, however, enforce automatic removing on updates by
setting this option to ``on``, ``yes`` or ``true``.

* ``user``
Default: system-dependent

You can optionally set a username that should own created
directories. The username must be valid name (not an uid) and the
system must support setting a user ownership for files. Of
course, the running process must have the permission to set the
requested user.

* ``group``
Default: system-dependent

You can optionally set a usergroup that should own created
directories.The group name must be a valid name (not a gid) and
the system must support setting a group ownership for files. Of
course, the running process must have the permission to set the
requested group.

* ``mode``
Default: system-dependent

You can optionally set file permissions for created directories
as octal numbers as usually used on Unix systems. These file
permissions will be set for each created directory if the running
process is allowed to do so.

Normally, a value of ``0700`` will give rwx permissions to the
owner and no permissions to group members or others.

If you don't specify a mode, the system default will be used.

* ``create-intermediate``
Default: ``yes``

If set to `no`, the parent directory of the path to create _must_
already exist when running the recipe (and an error occurs if not).

If set to `yes`, any missing intermediate directories will be
created. E.g. if creating a relative dir

``a/b/c/``

with ``create-intermediate`` set to ``no``, the relative path
``a/b/`` must exist already.


Simple creation of directories via buildout
-------------------------------------------

Lets create a minimal `buildout.cfg` file:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... ''')

Now we can run buildout:

>>> printx(system(join('bin', 'buildout')))
Installing mydir.
mydir: created path: /sample-buildout/parts/mydir

The directory was indeed created in the ``parts`` directory:

>>> ls_parts()
d mydir


As we did not specify a special path, the name of the created
directory is like the section name ``mydir``.


Creating a directory in a given path
------------------------------------

Lets create a minimal `buildout.cfg` file. This time the directory
has a name different from section name and we have to tell explicitly,
that we want it to be created in the ``parts/`` directory. We set the
``paths`` option to do so:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = ${buildout:parts-directory}/myotherdir
... ''')

Now we can run buildout:

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
mydir: created path: /sample-buildout/parts/myotherdir

The directory was indeed created:

>>> ls_parts()
d mydir
d myotherdir


Creating directories that are removed on updates
------------------------------------------------

We can tell the recipe that a directory should be removed on updates by using
the ``remove-on-update`` option:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... remove-on-update = true
... paths = newdir
... ''')

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
mydir: created path: /sample-buildout/newdir

The ``newdir/`` directory was created:

>>> ls('.')
- .installed.cfg
d bin
- buildout.cfg
d develop-eggs
d eggs
d newdir
d parts

We rewrite `buildout.cfg` and set a different path:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... remove-on-update = true
... paths = newdir2
... ''')

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
mydir: created path: /sample-buildout/newdir2

Now ``newdir/`` has vanished and ``newdir2`` exists:

>>> ls('.')
- .installed.cfg
d bin
- buildout.cfg
d develop-eggs
d eggs
d newdir2
d parts

Note, that the created directory will be removed on next modification
of `buildout.cfg`.

Setting User, Group, and Permissions
------------------------------------

You can optionally set ``user``, ``group``, or ``mode`` option for the
dirs to be created.

While ``user`` and ``group`` give the user/group that should own the
created directory (and all not existing intermediate directories),
``mode`` is expected to be an octal number to represent the directory
permissions in Unix style.

Of course, setting all these permissions and ownerships only works if
the system supports it and the running user has the permissions to do
so.

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = my/new/dir
... mode = 700
... user = %s
... group = %s
... ''' % (user, group))

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
mydir: created path: /sample-buildout/my
mydir: mode 0700, user 'USER', group 'GROUP'
mydir: created path: /sample-buildout/my/new
mydir: mode 0700, user 'USER', group 'GROUP'
mydir: created path: /sample-buildout/my/new/dir
mydir: mode 0700, user 'USER', group 'GROUP'

>>> lls('my')
drwx------ USER GROUP my/new

>>> lls('my/new')
drwx------ USER GROUP my/new/dir


These options are optional, so you can leave any of them out and the system
defaults will be used instead.

.. note:: Please note, that the permissions will only be set on newly
created directories. On updates only the permissions of the
leaf directory will be updated, not any intermediate
directories (except you set remove-on-update, which will
recreate also intermediate paths and set permissions
accordingly).

On updates only the leaf directories are changed
permission-wise. E.g. if we change the mode from the original buildout
from ``0700`` to ``0750``:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = my/new/dir
... remove-on-update = true
... mode = 750
... user = %s
... group = %s
... ''' % (user, group))

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
mydir: set permissions for /sample-buildout/my/new/dir
mydir: mode 0750, user 'USER', group 'GROUP'

the permissions of the leaf directory were updated:

>>> lls('my/new')
drwxr-x--- USER GROUP my/new/dir

while its parent's permissions are the same as before:

>>> lls('my')
drwx------ USER GROUP my/new


Clean up:

>>> import shutil
>>> shutil.rmtree('my')

Creating relative paths
-----------------------

If we specify a relative path, this path will be created relative to the
buildout directory:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = myrootdir
... ''')

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
mydir: created path: /sample-buildout/myrootdir


>>> ls('.')
- .installed.cfg
d bin
- buildout.cfg
d develop-eggs
d eggs
d myrootdir
d parts

The old directories will **not** vanish:

>>> ls_parts()
d mydir
d myotherdir


Creating intermediate paths
---------------------------

If we specify several levels of directories, the intermediate parts
will be created for us as well by default:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = myrootdir/other/dir/finaldir
... ''')

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
mydir: created path: /sample-buildout/myrootdir/other
mydir: created path: /sample-buildout/myrootdir/other/dir
mydir: created path: /sample-buildout/myrootdir/other/dir/finaldir

>>> ls('myrootdir', 'other', 'dir')
d finaldir

If we set the ``create-intermediate`` option to ``no`` (default is
``yes``), the resulting dir will only be created if the parent
directory exists already:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = leaf/dir/without/existing/parent
... create-intermediate = no
... ''')

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
While:
Installing mydir.
Error: Cannot create: /sample-buildout/leaf/dir/without/existing/parent
Parent does not exist or not a directory.

If you want to be explicit about the paths to be created (and which
not), you can set ``create-intermediate`` to ``no`` and simply list
each part of the path in ``paths`` option. This has the nice
sideeffect of setting permissions correctly also for intermediate
paths:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = mydir
... mydir/with
... mydir/with/existing
... mydir/with/existing/parent
... create-intermediate = no
... mode = 750
... ''')

>>> printx(system(join('bin', 'buildout')))
Installing mydir.
mydir: created path: /sample-buildout/mydir
mydir: mode 0750
mydir: created path: /sample-buildout/mydir/with
mydir: mode 0750
mydir: created path: /sample-buildout/mydir/with/existing
mydir: mode 0750
mydir: created path: /sample-buildout/mydir/with/existing/parent
mydir: mode 0750

This is more text to write down, but you can be sure that only
explicitly named dirs are created and permissions set accordingly.

For instance you can require a certain path to exist already and
create only the trailing path parts. Say, we expect a local `etc/` to
exist and want to create `etc/myapp/conf.d`. The following config
would do the trick:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = etc/myapp
... etc/myapp/conf.d
... create-intermediate = no
... mode = 750
... ''')

If the local `etc/` dir does not exist, we fail:

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
While:
Installing mydir.
Error: Cannot create: /sample-buildout/etc/myapp
Parent does not exist or not a directory.

But if this dir exists:

>>> mkdir('etc')
>>> printx(system(join('bin', 'buildout')))
Installing mydir.
mydir: created path: /sample-buildout/etc/myapp
mydir: mode 0750
mydir: created path: /sample-buildout/etc/myapp/conf.d
mydir: mode 0750

the subdirectories are created as expected.

It does, by the way, not matter, in which order you put the partial
parts into ``paths`` as this list is sorted before being
processed. So, any path `a/b/` will be processed before `a/b/c/`
regardless of the order in which both parts appear in the
configuration file.


Paths are normalized
--------------------

If we specify a non-normalized path (i.e. one that contains references
to parent directories or similar), the path will be normalized before
creating it:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = myroot/foo/../dir1/../bar/.
... ''')

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
mydir: created path: /sample-buildout/myroot
mydir: created path: /sample-buildout/myroot/bar

Only ``bar/`` will be created:

>>> ls('myroot')
d bar


Creating multiple paths in a row
--------------------------------

We can create multiple paths in one buildout section:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = myroot/dir1
... myroot/dir2
... ''')

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
mydir: created path: /sample-buildout/myroot/dir1
mydir: created path: /sample-buildout/myroot/dir2


>>> ls('myroot')
d bar
d dir1
d dir2

Note, that in this case you cannot easily reference the set path from
other recipes or templates. If, for example in a template you
reference::

root_dir = ${mydir:path}

the result will become::

root_dir = /path/to/buildout/dir1
path/to/buildout/dir2

If you specify only one path, however, the second line will not appear.

Use several sections using `z3c.recipe.mkdir` if you want to reference
different created paths from templates or similar.


Trailing slashes do not matter
------------------------------

It doesn't matter, whether you specify the paths with trailing slash
or without:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = myroot/dir3/
... myroot/dir4
... ''')

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
mydir: created path: /sample-buildout/myroot/dir3
mydir: created path: /sample-buildout/myroot/dir4

>>> ls('myroot')
d bar
d dir1
d dir2
d dir3
d dir4

Things to be aware of
---------------------

If you change the setting of some path, the old directory and all its
contents will **not** be deleted (as you might expect from a buildout
recipe):

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = path1
... ''')

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
mydir: created path: /sample-buildout/path1

>>> write(join('path1', 'myfile'), 'blah\n')
>>> ls('path1')
- myfile

Now we switch the setting of mydir to ``path2``:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = path2
... ''')

>>> printy(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
mydir: created path: /sample-buildout/path2
<BLANKLINE>

The file we created above is still alive:

>>> ls('path1')
- myfile


Things one should not do
------------------------

Trying to create directories that exist and are files
#####################################################

If a part of a given path already exists and is a file, an error is
raised:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = mydir
... offline = true
...
... [mydir]
... recipe = z3c.recipe.mkdir
... paths = rootdir2/somefile/foo
... ''')

Now we create the first part of the path beforehand:

>>> import os
>>> os.mkdir('rootdir2')

And make the second part of the path a file:

>>> write(join('rootdir2', 'somefile'),
... '''
... blah
... ''')

>>> printx(system(join('bin', 'buildout')))
Uninstalling mydir.
Installing mydir.
While:
Installing mydir.
Error: Cannot create directory: /.../rootdir2/somefile. It's a file.


Referencing options
-------------------

From other buildout recipe components you can reference the options of
`z3c.recipe.mkdir` like this::

${<sectionname>:paths}

where ``<sectionname>`` is the name of the `buildout.cfg` section
wherein you set the paths.

Options `mode`, `user`, and `group` are only referencable if they are
explicitly set.

Referencing without giving a path
#################################

You can reference also, if no path was given explicitly in
`buildout.cfg`:

>>> import z3c.recipe.mkdir
>>> buildout = dict(
... buildout = {
... 'directory': '/buildout',
... 'parts-directory' : '/buildout/parts',
... },
... somedir = {},
... )

>>> recipe = z3c.recipe.mkdir.Recipe(
... buildout, 'somedir', buildout['somedir'])

>>> printy(buildout['somedir']['paths'])
/buildout/parts/somedir

This means that if you have a `buildout.cfg` like this::

[buildout]
parts = somedir ...

[somedir]
recipe = z3c.recipe.mkdir

...

then for instance in a template you can write::

mydir = ${somedir:paths}

which will turn into::

mydir = /buildout/parts/somedir


Referencing with single path set
################################

If you reference a single path, you will get this back in references:

>>> buildout = dict(
... buildout = {
... 'directory': '/buildout',
... 'parts-directory' : '/buildout/parts',
... },
... somedir = {
... 'paths' : 'otherdir',
... },
... )

>>> recipe = z3c.recipe.mkdir.Recipe(
... buildout, 'somedir', buildout['somedir'])

>>> printy(buildout['somedir']['paths'])
/sample-buildout/otherdir

Referencing with multiple paths set
###################################

If you set several paths in `buildout.cfg`, you will get several lines
of output when referencing:

>>> buildout = dict(
... buildout = {
... 'directory': '/buildout',
... 'parts-directory' : '/buildout/parts',
... },
... somedir = {
... 'paths' : 'dir1 \n dir2',
... },
... )

>>> recipe = z3c.recipe.mkdir.Recipe(
... buildout, 'somedir', buildout['somedir'])

>>> printy(buildout['somedir']['paths'])
/sample-buildout/dir1
/sample-buildout/dir2


Changes
*******

0.6 (2013-05-21)
================

- Dropped support for deprecated ``path`` option (use ``paths`` instead).

- Added support for Python 3.2 / 3.3.

- Added ``setup.py docs`` alias: runs ``setup.py develop`` and then installs
documentation dependencies.

- Added ``setup.py dev`` alias: runs ``setup.py develop`` and then installs
testing dependencies.

- Updated docs and tests.

0.5 (2012-06-26)
==================

- Added support for ``create-intermediate`` option (``yes`` by default).

- Fixed bug: empty directory names were not excluded from ``paths``.

0.4 (2012-06-24)
================

- Added support for ``mode``, ``user``, and ``group`` options.

- Fixed (unnoticed?) bug when using the deprecated ``path`` option. In
that case the default path (``parts/<sectionname>``) was created
instead of the given one.

- Shortened main code.

- Updated tests to run with ``zc.buildout`` 1.5, thus requiring at least this
version.

- Using python's ``doctest`` module instead of depreacted
``zope.testing.doctest``.


0.3.1 (2009-08-21)
==================

- Update options ``path`` and ``paths`` to be referencable.

- Output ``created`` message only if a directory was really created
but display this message also for intermediate directories.

0.3 (2009-08-20)
================

- Renamed ``path`` option to ``paths`` (plural). Please do not use
``path`` anymore!

- Created directories are now displayed during buildout runs.

- Changed default behaviour: directories created once will not be
removed on updates, except you require that explicitly.

- Added new option ``remove-on-update``: if set to ``yes``, ``true``
or ``on`` the set directories will be removed on updates of
``buildout`` configuration.


0.2 (2009-08-19)
================

- Make paths absolute and normalize them before creation.

- Support creation of several paths in a row.

- Added check whether a file exists as part of path and emit error.


0.1 (2009-08-17)
================

- Initial release.