82 lines
1.8 KiB
Python
82 lines
1.8 KiB
Python
|
import os
|
||
|
|
from .__init__ import Reader,Writer
|
||
|
|
import json
|
||
|
|
|
||
|
|
class DiskReader(Reader) :
|
||
|
|
"""
|
||
|
|
This class is designed to read data from disk (location on hard drive)
|
||
|
|
@pre : isready() == True
|
||
|
|
"""
|
||
|
|
|
||
|
|
def __init__(self,**params):
|
||
|
|
"""
|
||
|
|
@param path absolute path of the file to be read
|
||
|
|
"""
|
||
|
|
|
||
|
|
Reader.__init__(self)
|
||
|
|
self.path = params['path'] ;
|
||
|
|
|
||
|
|
def isready(self):
|
||
|
|
return os.path.exists(self.path)
|
||
|
|
def read(self,size=-1):
|
||
|
|
"""
|
||
|
|
This function reads the rows from a designated location on disk
|
||
|
|
@param size number of rows to be read, -1 suggests all rows
|
||
|
|
"""
|
||
|
|
|
||
|
|
f = open(self.path,'rU')
|
||
|
|
i = 1
|
||
|
|
for row in f:
|
||
|
|
|
||
|
|
i += 1
|
||
|
|
if size == i:
|
||
|
|
break
|
||
|
|
yield row
|
||
|
|
f.close()
|
||
|
|
class DiskWriter(Writer):
|
||
|
|
"""
|
||
|
|
This function writes output to disk in a designated location
|
||
|
|
"""
|
||
|
|
|
||
|
|
def __init__(self,**params):
|
||
|
|
if 'path' in params:
|
||
|
|
self.path = params['path']
|
||
|
|
else:
|
||
|
|
self.path = None
|
||
|
|
if 'name' in params:
|
||
|
|
self.name = params['name'];
|
||
|
|
else:
|
||
|
|
self.name = None
|
||
|
|
if os.path.exists(self.path) == False:
|
||
|
|
os.mkdir(self.path)
|
||
|
|
|
||
|
|
def isready(self):
|
||
|
|
"""
|
||
|
|
This function determines if the class is ready for execution or not
|
||
|
|
i.e it determines if the preconditions of met prior execution
|
||
|
|
"""
|
||
|
|
|
||
|
|
p = self.path is not None and os.path.exists(self.path)
|
||
|
|
q = self.name is not None
|
||
|
|
return p and q
|
||
|
|
def write(self,**params):
|
||
|
|
"""
|
||
|
|
This function writes a record to a designated file
|
||
|
|
@param label <passed|broken|fixed|stats>
|
||
|
|
@param row row to be written
|
||
|
|
"""
|
||
|
|
|
||
|
|
label = params['label']
|
||
|
|
row = params['row']
|
||
|
|
xchar = None
|
||
|
|
if 'xchar' is not None:
|
||
|
|
xchar = params['xchar']
|
||
|
|
path = ''.join([self.path,os.sep,label])
|
||
|
|
if os.path.exists(path) == False:
|
||
|
|
os.mkdir(path) ;
|
||
|
|
path = ''.join([path,os.sep,self.name])
|
||
|
|
f = open(path,'a')
|
||
|
|
row = self.format(row,xchar);
|
||
|
|
f.write(row)
|
||
|
|
f.close()
|
||
|
|
|