Helper Objects

acrylamid.helpers.memoize(key, value=None)

Persistent memory for small values, set and get in a single function. If you set a value, it returns whether the new value is different to the previous.

>>> memoize("Foo", 1)
False
>>> memoize("Foo", 1)
True
>>> memoize("Foo", 2)
False
>>> memoize("Foo")
2

Parameters:

• key – get value saved to key, if key does not exist, return None.
• value – set key to value

acrylamid.helpers.union(first, *args, **kwargs)

Takes a list of dictionaries and performs union of each. Can take additional key=values as parameters to overwrite or add key/value-pairs. No side-effects,

acrylamid.helpers.mkfile(fileobj, path, ctime=0.0, ns=None, force=False, dryrun=False)

Creates entry in filesystem. Overwrite only if fileobj differs.

Parameters:

• fileobj – rendered html/xml as file-like object
• path – path to write to
• ctime – time needed to compile
• force – force overwrite, even nothing has changed (defaults to False)
• dryrun – don’t write anything.

acrylamid.helpers.expand(url, obj, re=<_sre.SRE_Pattern object at 0x102b531e0>)

Substitutes/expands URL parameters beginning with a colon.

Parameters:

• url – a URL with zero or more :key words
• obj – a dictionary where we get key from

>>> expand('/:year/:slug/', {'year': 2012, 'slug': 'awesome title'})
'/2011/awesome-title/'

acrylamid.helpers.joinurl(*args)

Joins multiple urls pieces to one single URL without loosing the root (first element). If the URL ends with a slash, Acrylamid automatically appends index.html.

>>> joinurl('/hello/', '/world/')
'/hello/world/index.html'

acrylamid.helpers.safeslug(slug)

Generates an ASCII-only slug. Borrowed from http://flask.pocoo.org/snippets/5/

acrylamid.helpers.paginate(lst, ipp, func=lambda x: x, salt=None, orphans=0)

Yields a triple ((next, current, previous), list of entries, has changed) of a paginated entrylist. It will first filter by the specified function, then split the ist into several sublists and check wether the list or an entry has changed.

Parameters:

• lst – the entrylist containing Entry instances.
• ipp – items per page
• salt – uses as additional identifier in memoize
• orphans – avoid N orphans on last page

>>> for x, values, _, paginate(entryrange(20), 6, orphans=2):
...    print x, values
(None, 0, 1), [entries 1..6]
(0, 1, 2), [entries 7..12]
(1, 2, None), [entries 12..20]

acrylamid.helpers.safe(string)

Safe string to fit in to the YAML standard (hopefully). Counterpart to acrylamid.readers.unsafe().

acrylamid.helpers.system(cmd, stdin=None, **kwargs)

A simple front-end to python’s horrible Popen-interface which lets you run a single shell command (only one, semicolon and && is not supported by os.execvp(). Does not catch OSError!

Parameters:

• cmd – command to run (a single string or a list of strings).
• stdin – optional string to pass to stdin.
• kwargs – is passed to subprocess.Popen.

class acrylamid.helpers.event

This helper class provides an easy mechanism to give user feedback of created, changed or deleted files. As side-effect every it allows you to register your own functions to these events.

Acrylamid has the following, fairly self-explanatory events: create, update, skip, identical and remove. A callback receives the current namespace and the path. The namespace might be None if not specified by the originator, but it is recommended to achieve a informal standard:

• the views supply their lowercase name such as 'entry' or 'archive' as namespace.
• asset generation uses the 'assets' namespace.
• the init, import and new task use their name as namespace.

To make this clear, the following example just records all newly created items from the entry view:

from acrylamid.hepers import event

skipped = []

def callback(ns, path):

    if ns == 'entry':
        skipped.add(path)

event.register(callback, to=['create'])

Note

This class is a singleton and should not be initialized

count(event)

Parameters:event (string) – count calls of this particular event

classmethod register(callback, to=[])

Register a callback to a list of events. Everytime the event eventuates, your callback gets called with all arguments of this particular event handler.

Parameters:

• callback – a function
• to – a list of events when your function gets called

acrylamid.helpers.rchop(original_string, substring)

Return the given string after chopping of a substring from the end.

Parameters:

• original_string – the original string
• substring – the substring to chop from the end

acrylamid.helpers.discover(directories, index, filterfunc=<function <lambda> at 0x102b5d7d0>)

Import and initialize modules from directories list.

Parameters:

• directories – list of directories
• index – index function