ems/API/buffer.py
2014-01-30 18:42:36 +01:00

170 lines
4.9 KiB
Python

'''
Created on 29.01.2014
@author: rauchp
'''
from sys import stderr
from socket import gethostname
from Config.config import Config
from datetime import datetime
from flask import abort
### json test ###
from numpy import timedelta64, float64, int64
from datetime import date
from decimal import Decimal
from math import isnan
### LOAD CONFIG ###
c = Config()
conf = c.readConf()
api_host = gethostname() if conf['flask_server'] == '0.0.0.0' else conf['flask_server']
api_url = 'http://%s:%s' % (api_host, conf['flask_port'])
class Buffer(object):
error = {
'db_error' : {}
}
system = {
'00_config' : conf,
'0_request' : [],
'0_done' : [],
'device' : {},
'error' : error
}
_instance = None
_id = 0
def __new__(cls, *args, **kwargs):
# http://stackoverflow.com/questions/42558/python-and-the-singleton-pattern
if not cls._instance:
cls._instance = super(Buffer, cls).__new__(
cls, *args, **kwargs)
return cls._instance
def gen_start_url(self, l):
'''
generate a URL form a list
@param l: list of aspacts of the URL
@return: URL
'''
url = api_url
for i in l:
url = '%s/%s' % (url, i)
return url
def get_level(self, l):
'''
iterating over a dictionary on a given path
@param l: items witch tell the path to the value
@return: dictionary with the key and value of the last item in the list
'''
level = l.pop(0)
for i in l:
if isinstance(level, dict) and i in level:
level = level.get(i)
else:
abort(404)
self.set_href(level, self.gen_start_url(l)) #set all links above
return {l[-1] : level}
def generate_links(self, dic, url, postfix):
'''
generats a link to dic if dic is a dictionary
@param dic: variable that is being tested on a dictionary
@param url: previous url
@param postfix: appendix to the given url
'''
if isinstance(dic, dict):
if '00_config' in url.split('/'):
return
url = '%s/%s' % (url, postfix)
self.set_href(dic, url)
else:
return
def set_href(self, dic, url):
'''
set the ref link if dic is a dictionary
@param dic: variable that is being tested on a dictionary
@param url: url to the first dictionary
'''
if isinstance(dic, dict):
for i in dic.keys():
self.generate_links(dic.get(i), url, i)
dic.update({'000_href': url})
dic.update({'000_timestamp' : str(datetime.now())})
def foo(self, l, args):
'''
@param l: list
@param args: arguments from the reqest
@return: Dictionary
'''
del l[-1]
dic = self.get_level(l).get(l[-1])
if isinstance(dic, dict) and 'dyn' in dic:
message = 'generating view for %s' % (l[-1])
else:
abort(404)
return { l[-1] : message, 'args' : args.to_dict(flat=False)}
def value_to_json(self, value): #timedelta64, float64, int64
if isinstance(value, (date, timedelta64)):
return str(value)
elif isinstance(value, (Decimal, float64)):
return float(value)
elif isinstance(value, int64):
return int(value)
elif isinstance(value, float) and isnan(value):
return None
else:
return value
def update_buffer(self, push):
'''
Method to update the Buffer on the given path
@param push: message to push in the buffer
construction: key is the path
value is the dict
'''
## Test of valid push message ##
if not isinstance(push, dict):
stderr.write('error wrong parameter: Type is %s expect dict' %
push.__class__.__name__)
return
if len(push.keys()) not in [1]:
stderr.write('error wrong number of arguments: %s expect 1' %
len(push.keys()))
return
if not isinstance(push.get(push.keys()[0]) ,dict):
stderr.write('error value is not dict')
return
key = push.keys()[0]
value = push[key]
path = key.split('/')
if path[0] == '':
path.remove('')
sys = self.system
for k in path:
try:
sys = sys[k]
except KeyError:
stderr.write('error wrong path: %s' % k)
return
for k in value:
value[k] = self.value_to_json(value[k])
sys.update(value)
return key
def init_buffer(self):
self.system['reqest'].append('init')
pass