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lambdaJSON 0.2.19

Use json to serialize unsupported python types (and many more including functions, classes, exceptions, etc).

Package Documentation

Latest Version: 4.3


Serialize python standard types (function, tuple, class, memoryview, set, frozenset, exceptions, complex, range, bytes, bytearray, dict with number keys, byte keys or tuple keys, and etc) with json. lambdaJSON lets you serialize python standard library objects with json.

** From v0.2.19 you can use dumps, loads instead of serialize, deserialize. **

Typical usage:

#!/usr/bin/env python

>>> import lambdaJSON
>>> myComplexData = {True: (3-5j), (3+5j): b'json', (1, 2, 3): {b'lambda': [1, 2, 3, (3, 4, 5)]}}
>>> mySerializedData = lambdaJSON.serialize(myComplexData)
>>> myComplexData  == lambdaJSON.deserialize(mySerializedData)


To pass args and kwargs to the encoder/decoder simply pass them to the serialize/deserialize function, example for json:

>>> mySerializedData = lambdaJSON.serialize(myComplexData, sort_keys = True)
>>> myComplexData  == lambdaJSON.deserialize(mySerializedData, object_hook = my_hook)

It can be done for ujson too. You can also serialize python functions:

>>> import lambdaJSON
>>> def f(): print('lambdaJSON Rocks!')

>>> mySerializedFunction = lambdaJSON.serialize(f)
>>> myNewFunction  = lambdaJSON.deserialize(mySerializedFunction)
>>> myNewFunction()
'lambdaJSON Rocks!'

Changed int 0.2.4, for function deserialization you must pass a function which returns the list of globals for the function:

>>> import lambdaJSON
>>> y = 10
>>> def f(x): return x*y

>>> mySerializedFunction = lambdaJSON.serialize(f)
>>> myNewFunction  = lambdaJSON.deserialize(mySerializedFunction, globs = (lambda: globals()))
>>> myNewFunction(5)
>>> y = 3
>>> myNewFunction(5)

If no globs passed to function, the globs will be just the __builtins__ module. Note that passing globals will pass the lambdaJSONs globals and it will not work, if you want to include all the globals from where the deserialization function is called, just use globs = (lambda: globals()), else implement your own function. You can do some nice hacks too:

>>> z = 10
>>> def g():
        global z
        z += 1
        return {'z':z}

>>> def f(x,y): return x*y+z

>>> mySerializedFunction = lambdaJSON.serialize(f)
>>> myNewFunction  = lambdaJSON.deserialize(mySerializedFunction, globs = g)
>>> myNewFunction(2,3)
>>> myNewFunction(2,3)

You can serialize Builtin Exceptions like this:

>>> a = lambdaJSON.serialize(OSError('FILE NOT FOUND'))
>>> b = lambdaJSON.deserialize(a)
>>> raise b
Traceback (most recent call last):
  File "<pyshell#3>", line 1, in <module>
    raise b

introduced in version 0.2.15, you can now serialize basic classes and types. The support is basic, but I’m planning to develop the class serialization support in the next subversion. to deserialize a class, you must pass the globals function too, if you do not pass the globals, only __builtins__ will be passed to the class functions. this is an example to do it:

>>> class test(object):
        def __init__(self):
            self.var = 'lambdaJSON'

>>> serializedClass = lambdaJSON.serialize(test)
>>> newClass = lambdaJSON.deserialize(serializedClass, globs = lambda: globals())
>>> newClass().var

To check version, simply use lambdaJSON.__version__, or if you want to know which json lib is in use, try lambdaJSON.__json__

After the support for all types are added, I’m planning to release a query friendly version of this library, that will be in version 0.3.0.

The json lib

LambdaJSON first tries to import ujson, if it fails it will import simplejson, and if that fails too, the json lib will be imported. you can check which json lib is in use with lambdaJSON.__json__ variable.

Currently Supported Types

This types are covered in this version:

  1. Functions
  2. Bytes and Bytearrays
  3. Classes (basic support)
  4. Builtin Exceptions
  5. Tuples
  6. Complex
  7. Range
  8. Set and Frozenset
  9. Memoryview
  10. Dicts (With Number, Tuple, String, Bool and Byte keys)
  11. other json supported types

Changes from previous

You can now use dumps, loads instead of serialize, deserialize.

Project Info

Github project page: Mail me at: persian.writer [at]

Contact me if there were any issues or you had a feature request. you can also post issues on github.

File Type Py Version Uploaded on Size (md5) Source 2013-09-24 10KB