120 lines
3.4 KiB
Python
120 lines
3.4 KiB
Python
"""
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Data Transport - 1.0
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Steve L. Nyemba, The Phi Technology LLC
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This module is designed to serve as a wrapper to a set of supported data stores :
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- couchdb
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- mongodb
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- Files (character delimited)
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- Queues (Rabbmitmq)
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- Session (Flask)
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- s3
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The supported operations are read/write and providing meta data to the calling code
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Requirements :
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pymongo
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boto
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couldant
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@TODO:
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Enable read/writing to multiple reads/writes
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"""
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__author__ = 'The Phi Technology'
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import numpy as np
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import json
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import importlib
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# import couch
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# import mongo
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class IO:
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def init(self,**args):
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"""
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This function enables attributes to be changed at runtime. Only the attributes defined in the class can be changed
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Adding attributes will require sub-classing otherwise we may have an unpredictable class ...
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"""
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allowed = list(vars(self).keys())
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for field in args :
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if field not in allowed :
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continue
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value = args[field]
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setattr(self,field,value)
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class Reader (IO):
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"""
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This class is an abstraction of a read functionalities of a data store
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"""
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def __init__(self):
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pass
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def meta(self):
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"""
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This function is intended to return meta-data associated with what has just been read
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@return object of meta data information associated with the content of the store
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"""
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raise Exception ("meta function needs to be implemented")
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def read(**args):
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"""
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This function is intended to read the content of a store provided parameters to be used at the discretion of the subclass
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"""
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raise Exception ("read function needs to be implemented")
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class Writer(IO):
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def __init__(self):
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self.cache = {"default":[]}
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def log(self,**args):
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self.cache[id] = args
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def meta (self,id="default",**args):
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raise Exception ("meta function needs to be implemented")
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def format(self,row,xchar):
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if xchar is not None and isinstance(row,list):
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return xchar.join(row)+'\n'
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elif xchar is None and isinstance(row,dict):
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row = json.dumps(row)
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return row
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def write(self,**args):
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"""
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This function will write content to a store given parameters to be used at the discretion of the sub-class
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"""
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raise Exception ("write function needs to be implemented")
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def archive(self):
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"""
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It is important to be able to archive data so as to insure that growth is controlled
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Nothing in nature grows indefinitely neither should data being handled.
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"""
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raise Exception ("archive function needs to be implemented")
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def close(self):
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"""
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This function will close the persistent storage connection/handler
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"""
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pass
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class ReadWriter(Reader,Writer) :
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"""
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This class implements the read/write functions aggregated
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"""
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pass
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# class factory :
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# @staticmethod
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# def instance(**args):
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# """
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# This class will create an instance of a transport when providing
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# :type name of the type we are trying to create
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# :args The arguments needed to create the instance
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# """
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# source = args['type']
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# params = args['args']
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# anObject = None
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# if source in ['HttpRequestReader','HttpSessionWriter']:
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# #
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# # @TODO: Make sure objects are serializable, be smart about them !!
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# #
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# aClassName = ''.join([source,'(**params)'])
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# else:
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# stream = json.dumps(params)
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# aClassName = ''.join([source,'(**',stream,')'])
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# try:
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# anObject = eval( aClassName)
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# #setattr(anObject,'name',source)
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# except Exception,e:
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# print ['Error ',e]
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# return anObject |