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Fetching data from memcached

I have to fetch data from memcached. But my code is fetching it from the database.
The pseudo code is as follows:
given a URL, try finding that page in the cache
if the page is in the cache:
return the cached page
else:
generate the page
save the generated page in the cache (for next time)
return the generated page
My python Code is as follows:
class CachedAPIView(APIView):
def get_queryset(self,request):
return function(self,request.data)
def get_object(self,queryset=None):
obj = cache.get('%s-%s'%(self.modelName.lower(),self.kwargs['pk']),None)
if not obj:
obj=super(CachedAPIView,self).get_object(queryset)
cache.set('%s-%s'%(self.modelName.lower(),self.kwargs['pk']),obj)
class ABC(CachedAPIView):
def fun(self,request,format=None):
request.data['PubIp']=getUserIP(request)
returnData=CachedAPIView.get_queryset(self,request)
if returnData == "TOKEN_ERROR":#token error
.....
elif returnData == "RECORD_NOT_FOUND":#bad request
......
else:
......
Any help would be appreciated. Thanks!

I have tried this code and it worked.
import hashlib
import json
from django.core.cache import cache
from .views import *
class CacheService():
def __init__(self, view=None, **kwargs):
self.data = kwargs
self.data.update({'view_name': view})
self.key = self.prepare_key()
def prepare_key(self):
return hashlib.md5(json.dumps(self.data, sort_keys=True).encode('utf-8')).hexdigest()
def set_to_cache(self, qs):
cache.set(self.key, qs)
def unset_cache(self, qs):
cache.set(self.key, None)
def delete_key_value(self):
cache.delete(self.key)
def get_from_cache(self):
return cache.get(self.key, None)
def clear_all_cache(self):
cache.clear()
This is cache.py file. The view to be cached is given below:
class MyView(APIView):
def post(self,request,format=None):
'''
'''
Data=my_function()
cache_service = CacheService(qs_type='my_function()')
event_queryset = cache_service.get_from_cache()
if not event_queryset:
event_queryset = my_function()
cache_service.set_to_cache(event_queryset)
if event_queryset == "TOKEN_ERROR":#token error
............
elif event_queryset == "RECORD_NOT_FOUND":#bad request
.............
else:
......................

Timeit module for qgis plugin

I'd like to use the python module timeit to time some functions in my QGIS plugin.
Here, I've called the time it function within a function that I call at the end of the last function. It seems, though, that the plugin is taking even longer to run than usual and I am wondering if i'm calling the timer in the wrong place. Is there a better way to set this up?
class myPluginName:
def firstFunction(self):
...
self.secondFunction()
def secondFunction(self):
...
self.timeThings()
def run(self):
self.firstFunction()
def timeThings(self):
QMessageBox.information(None, 'First Function', 'Time : %s' % timeit.timeit(self.firstFunction,number=1)
QMessageBox.information(None, 'Second Function', 'Time : %s' % timeit.timeit(self.secondFunction,number=1)
UPDATE: After following some advice, i've tried to implement the wrapper in the following way. I get however, a TypeError: firstFunction() takes exactly 1 argument (2 given) on ret = func(**args, **kwargs)
def time_func(func):
try:
name = func.__name__
except:
name = func.f__name
def tf_wrapper(*args, **kwargs):
t = time.time()
ret = func(*args, **kwargs)
QMessageLog.logMessage("{}: {}".format(name, time.time() - t))
return ret
return tf_wrapper
class myPlugin:
def initGui(self):
QObject.connect(self.dlg.ui.comboBox,SIGNAL("currentIndexChanged(int)"), self.firstFunction)
#time_func
def firstFunc(self):
registry = QgsMapLayerRegistry.instance()
firstID = str(self.dlg.ui.firstCombo.itemData(self.dlg.ui.firstCombo.currentIndex()))
secondID = str(self.dlg.ui.secondCombo.itemData(self.dlg.ui.secondCombo.currentIndex()))
self.firstLayer = registry.mapLayer(firstID)
self.secondLayer = registry.mapLayer(secondID)
#time_func
def secondFunc(self):
...
self.thirdFunc()
def thirdFunct(self):
...
def run(self):
self.dlg.ui.firstCombo.clear()
self.dlg.ui.secondCombo.clear()
for layer in self.iface.legendInterface().layers():
if layer.type() == QgsMapLayer.VectorLayer:
self.dlg.ui.firstCombo.addItem(layer.name(), layer.id())
self.dlg.ui.secondCombo.addItem(layer.name(), layer.id())
result = self.dlg.exec_()
if result == 1:
self.secondFunction()

OK, I don't know your exact situation, but I'd set it up though decorators:
import time
def time_func(func):
try:
name = func.__name__
except:
name = func.f_name
def tf_wrapper(*args, **kwargs):
t = time.time()
ret = func(*args, **kwargs)
print("{}: {}".format(name, time.time() - t)) # Or use QMessageBox
return ret
return tf_wrapper
class myPluginName:
#time_func
def firstFunction(self):
pass
#time_func
def secondFunction(self):
pass
def run(self):
self.firstFunction()
myPluginName().firstFunction()
With this code, any function wrapped in time_func will have the time taken to execute the function printed when it returns, along with its name. E.g. running it will print:
firstFunction: 1.430511474609375e-06
For your TypeError, you need to change;
def firstFunction(self):
pass
To:
def firstFunction(self, index):
pass

How do I use a global variable in cherrypy?

I need to access a global variable that keeps its state over diffferent server requsts.
In this example the global variable is r and it is incremented at each request.
How can I make r global in cherrypy?
import cherrypy
import urllib
class Root(object):
#cherrypy.expose
def index(self, **params):
jsondict = [('foo', '1'), ('fo', '2')]
p = urllib.urlencode(jsondict)
if r!=1
r=r+1
raise cherrypy.HTTPRedirect("/index?" + p)
return "hi"
cherrypy.config.update({
'server.socketPort': 8080
})
cherrypy.quickstart(Root())
if __name__ == '__main__':
r=1

To access a global variable, you have to use the global keyword followed by the name of the variable. However, if r is going to be used only in the Root class, I recommend you to declare it as a class variable:
class Root(object):
r = 1
#cherrypy.expose
def index(self, **params):
#...
if Root.r != 1:
Root.r += 1
#...

I had the same problem. It was solved after realizing my program could access the member variables of an imported library.
First, make a file called myglobals.py and put this in it
r=0
visitors = 0
Then in your server:
import myglobals
class Root(object):
#cherrypy.expose
def index(self, **params):
#...
if myglobals.r != 1:
myglobals.r += 1
#...

Python : Object is not avaialbe on different file

I have created a singlton Here is the class description.
allsms.py
from DB.models import ApiKey,ServiceProvider
from DB.messagenet import MessageNet
class SMSMgr( object ):
_instance = None
_allsp = []
def __init__(self):
pass
def __new__(cls, *args, **kwargs):
if not cls._instance :
cls._instance = super(SMSMgr, cls).__new__(
cls, *args, **kwargs)
return cls._instance
def loadsettings(self):
get_all_sp = ServiceProvider.objects.filter(status = False)
for obj in get_all_sp:
cla = obj.class_Name
a=globals()[str(obj.class_Name)](obj.userName,obj.password,obj.sendingurl)
self._allsp.append(a)
#print self._allsp
def reload(self):
self._allsp = []
get_all_sp = ServiceProvider.objects.filter(status = False)
for obj in get_all_sp:
cla = obj.class_Name
a=globals()[str(obj.class_Name)](obj.userName,obj.password,obj.sendingurl)
self._allsp.append(a)
def send(self):
print "+++++++++++++++++++== Global send "
if __name__ == "__main__":
b = SMSMgr()
b.loadsettings()
Now in test.py file of the same directory I am trying to use the singleton object which stored in the _allsp variable like.
from SMShandler.allsms import SMSMgr
b = SMSMgr()
#b.loadsettings()
print b._allsp
This is printing empty list. But when I am doing like this:
b = SMSMgr()
b.loadsettings()
print b._allsp
it is printing the list of objects .
My question is, if the above design is singlton then why print b._allsp is printing empty list in test.py? I am already loading loadsettings in the allsms.py file .

You are running loadsettings() in an if __name__ == "__main__" block:
if __name__ == "__main__":
b = SMSMgr()
b.loadsettings()
The purpose of such a block is to happen only when the code is run directly (like python allsms.py). That means it won't happen when it is imported in the line:
from SMShandler.allsms import SMSMgr
If you put the line b.loadsettings() outside of the if block, you'll see that it will already be loaded.

Generate graph of the imports

I'm getting close to my final goal, which is to generate a nice graph between modules and other imported modules.
For example if x imports from y and z, and y imports from t and v I would like to have:
x -> y, z
y -> t, v
Now I already have my import hook defined as below, but running it on a simple file I don't get what I would expect:
python study_imports.py CollectImports simple.py
('study_imports.py', 'study_imports')
Where simple.py actually imports from study_imports.
The problem is that I want to see "simple.py" instead of "study_imports.py", is there a way to get the path of the file actually importing the other module?
class CollectImports(object):
"""
Import hook, adds each import request to the loaded set and dumps
them to file
"""
def __init__(self, output_file):
self.loaded = set()
self.output_file = output_file
def __str__(self):
return str(self.loaded)
def cleanup(self):
"""Dump the loaded set to file
"""
dumped_str = '\n'.join(x for x in self.loaded)
open(self.output_file, 'w').write(dumped_str)
def find_module(self, module_name, package=None):
#TODO: try to find the name of the package which is actually
#importing something else, and how it's doing it
#use a defualtdict with empty sets as the storage for this job
entry = (__file__, module_name)
self.loaded.add(str(entry))

Maybe with the inspect module.
Module a.py
import inspect
print inspect.stack()
Module b.py
import a
when running b.py, I got :
[
(<frame object at 0x28a9b70>, '/path/a.py', 5, '<module>', ['print inspect.stack()\n'], 0),
(<frame object at 0x28a9660>, 'b.py', 2, '<module>', ['import to_import\n'], 0)
]
Looks like the second frame contains what you need.

So I looked in snakefood a bit better and I ended up rewriting my code using the AST.
Snakefood still uses the compiler, which is deprecated and much slower than using the ast.
The result is great, for example this is a visitor:
from ast import parse, NodeVisitor
class ImportVisitor(NodeVisitor):
def __init__(self):
self.imported = set()
super(ImportVisitor, self).__init__()
def __str__(self):
return '\n'.join(x for x in self.imported)
def visit_Import(self, node):
for n in node.names:
self.imported.add(n.name)
#that we are using
def visit_ImportFrom(self, node):
self.imported.add(node.module)
Which can be usef for example as:
def gen_module_imports(mod):
try:
at = parse(open(mod).read())
except SyntaxError:
print("file %s has a syntax error, please fix it" % mod)
return []
else:
v = ImportVisitor()
v.visit(at)
return v.imported

The inspect trick seems to work fine :)
I get something like simple.py: set(['study_imports']) in the imports.log.
Class CollectImports(object):
"""
Import hook, adds each import request to the loaded set and dumps
them to file
"""
def __init__(self, output_file):
self.loaded = defaultdict(lambda: set())
self.output_file = output_file
def __str__(self):
return str(self.loaded)
def cleanup(self):
"""Dump the loaded set to file
"""
dumped_str = '\n'.join(('%s: %s' % (k, v)) for k, v in self.loaded.items())
open(self.output_file, 'w').write(dumped_str)
def find_module(self, module_name, package=None):
st = inspect.stack()
self.loaded[st[1][1]].add(module_name)