Python: Object Serialization with pickle
Serialization:
#!/usr/bin/env python
import cPickle as pickle
import os
import sys
sys.path.insert(0, os.path.abspath(os.path.dirname(sys.argv[0])))
class Package(object):
def __init__(self, pn, pv):
self.pn = pn
self.pv = pv
def __str__(self):
return str(self.pn)+' '+str(self.pv)
def serialize(cachefile, *listPackages):
'''
serialize a list of packages to the specified cache file
'''
pickler = pickle.Pickler(cachefile)
for package in listPackages:
pickler.dump(package)
def main(argv=None):
if len(argv) != 1:
cachefile = 'tmp.dat'
else:
cachefile = argv[0]
p1 = Package('package1', 1.0)
p2 = Package('package1', 2.0)
p3 = Package('package1', 3.0)
p4 = Package('package1', 4.0)
p5 = Package('package1', 5.0)
with open(cachefile, 'wb') as cachefile:
serialize(cachefile, p1, p2, p3, p4, p5)
if __name__ == '__main__':
main(sys.argv[1:])
De-serialization
#!/usr/bin/env python
import cPickle as pickle
import os
import sys
sys.path.insert(0, os.path.abspath(os.path.dirname(sys.argv[0])))
from serialize import Package
def main(argv=None):
'''
read the cache file and print the contents
'''
if len(argv) != 1:
cachefile = 'tmp.dat'
else:
cachefile = argv[0]
with open(cachefile, 'rb') as cachefile:
pickled = pickle.Unpickler(cachefile)
while cachefile:
try:
package = pickled.load()
except:
break
if isinstance(package, Package):
print package
if __name__ == '__main__':
main(sys.argv[1:])
Result
chenqi@chenqi-OptiPlex-760:~/mypro/python$ ./serialize.py cache.dat
chenqi@chenqi-OptiPlex-760:~/mypro/python$ ./de-serialize.py cache.dat
package1 1.0
package1 2.0
package1 3.0
package1 4.0
package1 5.0