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86 lines
1.9 KiB
Python
86 lines
1.9 KiB
Python
5 years ago
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import os
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from .__init__ import Reader,Writer
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import json
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class DiskReader(Reader) :
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"""
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This class is designed to read data from disk (location on hard drive)
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@pre : isready() == True
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"""
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def __init__(self,**params):
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"""
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@param path absolute path of the file to be read
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"""
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Reader.__init__(self)
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self.path = params['path'] ;
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def isready(self):
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return os.path.exists(self.path)
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def read(self,size=-1):
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"""
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This function reads the rows from a designated location on disk
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@param size number of rows to be read, -1 suggests all rows
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"""
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f = open(self.path,'rU')
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i = 1
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for row in f:
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i += 1
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if size == i:
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break
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yield row
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f.close()
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class DiskWriter(Writer):
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"""
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This function writes output to disk in a designated location
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"""
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def __init__(self,**params):
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if 'path' in params:
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self.path = params['path']
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else:
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self.path = None
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if 'name' in params:
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self.name = params['name'];
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else:
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