degal: degal/utils.py@d9cf1e272e90 (annotated)

44 533b7e8b5d3b strip copyright/license boilerplate from modules, except dexif and formatbytes Tero Marttila <terom@fixme.fi> parents: 41 diff changeset	1	"""
533b7e8b5d3b strip copyright/license boilerplate from modules, except dexif and formatbytes Tero Marttila <terom@fixme.fi> parents: 41 diff changeset	2	Miscellaneous utilities
533b7e8b5d3b strip copyright/license boilerplate from modules, except dexif and formatbytes Tero Marttila <terom@fixme.fi> parents: 41 diff changeset	3	"""
533b7e8b5d3b strip copyright/license boilerplate from modules, except dexif and formatbytes Tero Marttila <terom@fixme.fi> parents: 41 diff changeset	4
59 fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	5	import functools
23 10841abbc01f taggr2, which is starting to shape up terom parents: 20 diff changeset	6
96 d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	7	class LazyProperty (object) :
12 c2d8e9a754a1 Major code restructuring. Version is now 0.5, templates use Mako, and the code is split off into several files under lib/ terom parents: diff changeset	8	"""
84 891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	9	Lazy-loaded cached properties.
891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	10
891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	11	This functions by overriding the class's property attribute with the actual value attribute in the instance's
891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	12	dict, causing all future attribute lookups to return that directly.
96 d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	13
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	14	>>> class Foo (object) :
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	15	... counter = 0
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	16	... @lazy_load
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	17	... def foo (self) :
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	18	... self.counter += 1
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	19	... return self.counter
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	20	...
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	21	>>> foo = Foo(); foo.foo, foo.foo, foo.counter
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	22	(1, 1, 1)
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	23
12 c2d8e9a754a1 Major code restructuring. Version is now 0.5, templates use Mako, and the code is split off into several files under lib/ terom parents: diff changeset	24	"""
c2d8e9a754a1 Major code restructuring. Version is now 0.5, templates use Mako, and the code is split off into several files under lib/ terom parents: diff changeset	25
59 fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	26	def __init__ (self, func) :
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	27	"""
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	28	Initialize with no value
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	29	"""
75 18b3b1926720 fix utils.LazyProperty Tero Marttila <terom@fixme.fi> parents: 73 diff changeset	30
84 891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	31	# the getter function
75 18b3b1926720 fix utils.LazyProperty Tero Marttila <terom@fixme.fi> parents: 73 diff changeset	32	self.func = func
84 891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	33
891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	34	# the attribute name
75 18b3b1926720 fix utils.LazyProperty Tero Marttila <terom@fixme.fi> parents: 73 diff changeset	35	self.name = func.__name__
19 8d3ffd87cb0b * move cgi-bin to de-cgi-bin so it doesn't conflict with my default alias... need to come up with a real solution to this terom parents: 18 diff changeset	36
73 8897352630a5 misc. stuff in gallery.py utils.py Tero Marttila <terom@fixme.fi> parents: 59 diff changeset	37	def run (self, obj) :
59 fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	38	"""
84 891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	39	Run the background func and return the to-be-cached value.
891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	40
891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	41	`obj` is the object instance
59 fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	42	"""
28 70b6c13d084f fancy new log format terom parents: 27 diff changeset	43
75 18b3b1926720 fix utils.LazyProperty Tero Marttila <terom@fixme.fi> parents: 73 diff changeset	44	return self.func(obj)
73 8897352630a5 misc. stuff in gallery.py utils.py Tero Marttila <terom@fixme.fi> parents: 59 diff changeset	45
84 891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	46	def store (self, obj, value) :
73 8897352630a5 misc. stuff in gallery.py utils.py Tero Marttila <terom@fixme.fi> parents: 59 diff changeset	47	"""
84 891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	48	Store the cached value, overring ourself
73 8897352630a5 misc. stuff in gallery.py utils.py Tero Marttila <terom@fixme.fi> parents: 59 diff changeset	49	"""
96 d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	50
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	51	# print "[%x] %r.__dict__[%r] = %r" % (id(obj), obj, self.name, value)
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	52
84 891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	53	obj.__dict__[self.name] = value
73 8897352630a5 misc. stuff in gallery.py utils.py Tero Marttila <terom@fixme.fi> parents: 59 diff changeset	54
75 18b3b1926720 fix utils.LazyProperty Tero Marttila <terom@fixme.fi> parents: 73 diff changeset	55	def __get__ (self, obj, owner) :
59 fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	56	"""
84 891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	57	Generate the value, store it as the attribute and return it.
59 fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	58	"""
96 d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	59
84 891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	60	# compute value
891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	61	value = self.run(obj)
59 fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	62
84 891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	63	# store it
891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	64	self.store(obj, value)
891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	65
891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	66	# return it
891545a38a2b change utils.LazyProperty to store the cached value using obj.__dict__ Tero Marttila <terom@fixme.fi> parents: 75 diff changeset	67	return value
96 d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	68
59 fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	69	class LazyIteratorProperty (LazyProperty) :
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	70	"""
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	71	A lazy-loaded property that automatically converts an iterator/genexp into a list.
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	72	"""
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	73
73 8897352630a5 misc. stuff in gallery.py utils.py Tero Marttila <terom@fixme.fi> parents: 59 diff changeset	74	def run (self, obj) :
59 fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	75	"""
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	76	Wrap LazyProperty.run to return a list
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	77	"""
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	78
96 d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	79	return list(self.func(obj))
59 fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	80
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	81	lazy_load = LazyProperty
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	82	lazy_load_iter = LazyIteratorProperty
fbbe956229cc remove old utils and write some new ones Tero Marttila <terom@fixme.fi> parents: 44 diff changeset	83
96 d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	84	# testing
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	85	if __name__ == '__main__' :
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	86	import doctest
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	87
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	88	doctest.testmod()
d9cf1e272e90 fix LazyProperty to not inherit from property, so as to act as a non-data descriptor, which can then be overriden by per-instance __dict__ values Tero Marttila <terom@fixme.fi> parents: 84 diff changeset	89

author	Tero Marttila <terom@fixme.fi>
	Thu, 11 Jun 2009 22:50:21 +0300
changeset 96	d9cf1e272e90
parent 84	891545a38a2b
child 109	66a01c0806f1
permissions	-rw-r--r--