static-file: properly set/use cache header for static file (closes #2255013)
This changesets enables the standard http cache mechanism where the static
controller may reply "304 Not modified" based on `last-modified` in HTTP
response and `if-modified-since` in HTTP query. The last modified time is
computed using the file-system information.
The pre-existing logic using an `Expires` header to prevent client from sending
request stay in place. The new logic just prevents sending the file again if not
necessary.
"""https://pastebin.logilab.fr/show/860/"""
from logilab.astng import MANAGER, nodes, scoped_nodes
from logilab.astng.builder import ASTNGBuilder
def turn_function_to_class(node):
"""turn a Function node into a Class node (in-place)"""
node.__class__ = scoped_nodes.Class
node.bases = ()
# remove return nodes so that we don't get warned about 'return outside
# function' by pylint
for rnode in node.nodes_of_class(nodes.Return):
rnode.parent.body.remove(rnode)
# that seems to be enough :)
def cubicweb_transform(module):
# handle objectify_predicate decorator (and its former name until bw compat
# is kept). Only look at module level functions, should be enough.
for assnodes in module.locals.values():
for node in assnodes:
if isinstance(node, scoped_nodes.Function) and node.decorators:
for decorator in node.decorators.nodes:
for infered in decorator.infer():
if infered.name in ('objectify_predicate', 'objectify_selector'):
turn_function_to_class(node)
break
else:
continue
break
# add yams base types into 'yams.buildobjs', astng doesn't grasp globals()
# magic in there
if module.name == 'yams.buildobjs':
from yams import BASE_TYPES
for etype in BASE_TYPES:
module.locals[etype] = [scoped_nodes.Class(etype, None)]
# add data() to uiprops module
if module.name.split('.')[-1] == 'uiprops':
fake = ASTNGBuilder(MANAGER).string_build('''
def data(string):
return u''
''')
module.locals['data'] = fake.locals['data']
def register(linter):
"""called when loaded by pylint --load-plugins, nothing to do here"""
MANAGER.register_transformer(cubicweb_transform)