rajaramanathan/strategy.py

## strategy.py
from __future__ import print_function
import os
import csv
from csv import Sniffer
from csv import reader
from csv import DictReader

HTML_TEMPLATE="""<html><body><table>%s</table></body></html>"""

class CsvConverter:
    ''' Abstract class or interface for conversion of csv file'''
    def convert(self,csv):
        pass #abstract method

class Csv2Html(CsvConverter):
    ''' Covert Csv to html table with alternating row colors'''

    def convert(self,csv):
        ''' convert the csv file to html file '''
        htmltable = ''
        csvfile = open(csv)
        dialect = Sniffer().sniff(csvfile.read(2048))
        csvfile.seek(0) #rewind after sniffing
        csvreader = reader(csvfile,dialect)
        i = 0
        for line in csvreader:
            #print line
            if i == 0: #header row
                htmltable += '<tr class="head">'
            elif i % 2 == 0: #even row
                htmltable += '<tr class="even">'
            else: #odd row
                htmltable += '<tr class="odd">'

            for col in line:
                htmltable += '<td>%s</td>'%col
            htmltable += '</tr>'
            i += 1

        return HTML_TEMPLATE%htmltable

    def __str__(self):
        return 'Csv2Html'

class Csv2Xml(CsvConverter):
    ''' Covert Csv to Xml '''

    def __init__(self,linetag='row'):
        ''' Constructor '''
        self.linetag = linetag

    def convert(self,csv):
        ''' convert the csv file to xml file '''
        xml = '<?xml version="1.0" encoding="UTF-8"?>'
        xml += "<table>" + os.linesep
        csvfile = open(csv)
        csvreader = DictReader(csvfile)
        for row in csvreader:
            xml += '<%s>'%self.linetag + os.linesep
            for colname,colvalue in row.iteritems():
                xml += '<%s>%s</%s>'%(colname,colvalue.replace('\n', ' ').replace('\r', ''),colname) + os.linesep
            xml += '</%s>'%self.linetag + os.linesep
        xml += "</table>" + os.linesep
        return xml

    def __str__(self):
        return 'Csv2Xml'

class CsvUtil(object):
    ''' A wrapper or utility class for dealing with csv files '''

    def __init__(self,csv):
        ''' constructor '''
        self.csv = csv
        self._numlines = None #this information is computed lazily
        self._numcols = None #this information is gathered lazily
        self._wellformed = None #this information is gathered lazily
        self._converter = Csv2Html() #default converter

    def _gatherstats(self):
        ''' gather basic stats on the csv '''

        with open(self.csv) as csvfile:
            dialect = csv.Sniffer().sniff(csvfile.read(2048))
            csvfile.seek(0) #rewind
            reader = csv.reader(csvfile,dialect)
            self._numlines = 0
            self._wellformed = True
            self._numcols = 0
            for line in reader:
                self._numlines += 1
                if self._numcols != len(line):
                    self._wellformed = False

    def convert(self):
        ''' convert the csv file to another format '''
        return self._converter.convert(self.csv)

    def get_wellformed(self):
        ''' a csv is wellformed if all the lines have same number of columns '''
        if not self._wellformed:
            self._gatherstats()
        return self._wellformed

    def get_numlines(self):
        ''' number of lines in the csv files '''
        if not self._numlines:
            self._gatherstats()
        return self._numlines

    def get_numcols(self):
        ''' number of lines in the csv files '''
        if not self._numcols:
            self._gatherstats()
        return self._numcols

    def get_converter(self):
        ''' getter for converter '''
        return self._converter

    def set_converter(self,value):
        self._converter = value

    #properties
    wellformed = property(get_wellformed)
    numlines = property(get_numlines)
    numcols = property(get_numcols)
    converter = property(get_converter,set_converter)


def main():
    csvfile = os.path.expanduser(r"~/Downloads/sample.csv")
    outputDir = os.path.dirname(csvfile) #write the html and xml to this directory

    util = CsvUtil(csvfile) # my utility class for handling csv
    htmlFile = os.path.join(outputDir,"sample.csv.html")
    with open(htmlFile, 'w') as f:
        print(util.convert(), file=f)

    #now changing my converter at run time :-)
    util.converter = Csv2Xml()
    xmlFile = os.path.join(outputDir,"sample.csv.xml")
    with open(xmlFile, 'w') as f:
        print(util.convert(), file=f)

if __name__ == "__main__":
    main()
	from __future__ import print_function
	import os
	import csv
	from csv import Sniffer
	from csv import reader
	from csv import DictReader

	HTML_TEMPLATE="""<html><body><table>%s</table></body></html>"""

	class CsvConverter:
	''' Abstract class or interface for conversion of csv file'''
	def convert(self,csv):
	pass #abstract method

	class Csv2Html(CsvConverter):
	''' Covert Csv to html table with alternating row colors'''

	def convert(self,csv):
	''' convert the csv file to html file '''
	htmltable = ''
	csvfile = open(csv)
	dialect = Sniffer().sniff(csvfile.read(2048))
	csvfile.seek(0) #rewind after sniffing
	csvreader = reader(csvfile,dialect)
	i = 0
	for line in csvreader:
	#print line
	if i == 0: #header row
	htmltable += '<tr class="head">'
	elif i % 2 == 0: #even row
	htmltable += '<tr class="even">'
	else: #odd row
	htmltable += '<tr class="odd">'

	for col in line:
	htmltable += '<td>%s</td>'%col
	htmltable += '</tr>'
	i += 1

	return HTML_TEMPLATE%htmltable

	def __str__(self):
	return 'Csv2Html'

	class Csv2Xml(CsvConverter):
	''' Covert Csv to Xml '''

	def __init__(self,linetag='row'):
	''' Constructor '''
	self.linetag = linetag

	def convert(self,csv):
	''' convert the csv file to xml file '''
	xml = '<?xml version="1.0" encoding="UTF-8"?>'
	xml += "<table>" + os.linesep
	csvfile = open(csv)
	csvreader = DictReader(csvfile)
	for row in csvreader:
	xml += '<%s>'%self.linetag + os.linesep
	for colname,colvalue in row.iteritems():
	xml += '<%s>%s</%s>'%(colname,colvalue.replace('\n', ' ').replace('\r', ''),colname) + os.linesep
	xml += '</%s>'%self.linetag + os.linesep
	xml += "</table>" + os.linesep
	return xml

	def __str__(self):
	return 'Csv2Xml'

	class CsvUtil(object):
	''' A wrapper or utility class for dealing with csv files '''

	def __init__(self,csv):
	''' constructor '''
	self.csv = csv
	self._numlines = None #this information is computed lazily
	self._numcols = None #this information is gathered lazily
	self._wellformed = None #this information is gathered lazily
	self._converter = Csv2Html() #default converter

	def _gatherstats(self):
	''' gather basic stats on the csv '''

	with open(self.csv) as csvfile:
	dialect = csv.Sniffer().sniff(csvfile.read(2048))
	csvfile.seek(0) #rewind
	reader = csv.reader(csvfile,dialect)
	self._numlines = 0
	self._wellformed = True
	self._numcols = 0
	for line in reader:
	self._numlines += 1
	if self._numcols != len(line):
	self._wellformed = False

	def convert(self):
	''' convert the csv file to another format '''
	return self._converter.convert(self.csv)

	def get_wellformed(self):
	''' a csv is wellformed if all the lines have same number of columns '''
	if not self._wellformed:
	self._gatherstats()
	return self._wellformed

	def get_numlines(self):
	''' number of lines in the csv files '''
	if not self._numlines:
	self._gatherstats()
	return self._numlines

	def get_numcols(self):
	''' number of lines in the csv files '''
	if not self._numcols:
	self._gatherstats()
	return self._numcols

	def get_converter(self):
	''' getter for converter '''
	return self._converter

	def set_converter(self,value):
	self._converter = value

	#properties
	wellformed = property(get_wellformed)
	numlines = property(get_numlines)
	numcols = property(get_numcols)
	converter = property(get_converter,set_converter)



	def main():
	csvfile = os.path.expanduser(r"~/Downloads/sample.csv")
	outputDir = os.path.dirname(csvfile) #write the html and xml to this directory

	util = CsvUtil(csvfile) # my utility class for handling csv
	htmlFile = os.path.join(outputDir,"sample.csv.html")
	with open(htmlFile, 'w') as f:
	print(util.convert(), file=f)

	#now changing my converter at run time :-)
	util.converter = Csv2Xml()
	xmlFile = os.path.join(outputDir,"sample.csv.xml")
	with open(xmlFile, 'w') as f:
	print(util.convert(), file=f)

	if __name__ == "__main__":
	main()