Skip to content

Serialize

JSONSerializable

JSON serialization for Python classes. Saves keyword arguments at construction, and also any state returned by the save_state method. Does not attempt to serialize code or any other attributes.

to make class a serializable, subclass JSONSerializable, and in the constructor use e.g. super().__init__(a=0, b=1 ...) with any keyword args which should be serialized.

override save_state and load_state to handle any mutable state.

Constructor args and return values of save_state can be other JSONSerializable objects, or any types which are already serializable by the standard library json module.

Source code in src/anguilla/serialize.py 
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
class JSONSerializable:
    """JSON serialization for Python classes.
    Saves keyword arguments at construction,
    and also any state returned by the `save_state` method.
    Does *not* attempt to serialize code or any other attributes.

    to make class a serializable, subclass JSONSerializable, 
    and in the constructor use e.g. `super().__init__(a=0, b=1 ...)`
    with any keyword args which should be serialized.

    override `save_state` and `load_state` to handle any mutable state.

    Constructor args and return values of `save_state` can be other JSONSerializable objects, or any types which are already serializable by
    the standard library `json` module.
    """
    def __init__(self, **kw):
        self._kw = deepcopy(kw)
        self._kw['__inst__'] = '.'.join((
            self.__class__.__module__,
            self.__class__.__name__))

    def _store(self):
        return {'__state__': self.save_state(), **self._kw}

    def save_state(self):
        """return object state in JSON serializable form"""
        return None

    def load_state(self, state):
        """restore from de-serialized state"""
        pass

load_state(state)

restore from de-serialized state

Source code in src/anguilla/serialize.py 
42
43
44
def load_state(self, state):
    """restore from de-serialized state"""
    pass

save_state()

return object state in JSON serializable form

Source code in src/anguilla/serialize.py 
38
39
40
def save_state(self):
    """return object state in JSON serializable form"""
    return None

get_cls(s)

convert a type name to a type, importing dependencies as needed

e.g. "somepackage.submodule.SomeClass" -> SomeClass

this works by doing: import somepackage import somepackage.submodule.SomeClass eval("somepackage.submodule.SomeClass")

this should work in most cases, but could possibly break if the package containing the type has a weird structure.

In cases where dependencies rename / reorganize their types, breaking old anguilla files, any translation of type names can be done here.

Source code in src/anguilla/serialize.py 
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
def get_cls(s):
    """convert a type name to a type, importing dependencies as needed

    e.g. "somepackage.submodule.SomeClass" -> SomeClass 

    this works by doing:
    import somepackage
    import somepackage.submodule.SomeClass
    eval("somepackage.submodule.SomeClass")

    this should work in most cases, but could possibly break if the package containing the type has a weird structure.

    In cases where dependencies rename / reorganize their types, breaking old
    anguilla files, any translation of type names can be done here.
    """

    # sanitize inputs
    assert all(item.isidentifier() for item in s.split('.')), s
    parts = s.split('.')

    ### backward compat translations ###
    if parts[0]=='iml': parts[0] = 'anguilla'

    pkg = parts[0]
    mod = '.'.join(parts[:-1])
    # import top level package the type belongs to
    exec(f'import {pkg}') 
    # import submodule the type is in
    exec(f'import {mod}')
    # convert string to type
    return eval(s)