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Serialization and deserialization

pykx.serialize

Module to help with serializing K objects without copying the data.

serialize 

serialize(obj, mode=6, wait=0)

Helper class to manage making 0 copy serialized K objects.

    Parameters:
        obj: The object to serialize.
        mode: The [capability level](https://code.kx.com/q/basics/ipc/#handshake)
            to use for serialization, defaults to the maximum value of 6.
        wait: The message type to use, defaults to 0.

    Note: The available message types to use are 0, 1, and 2.
        - 0: async
        - 1: sync
        - 2: response

        More information about the serialization of `K` objects can be found
        [here](https://code.kx.com/pykx/user-guide/advanced/serialization.html).

    Note: To access the memory view of the serialized object you can use the `data` property.
        If you need a copy of the data instead you can use the `copy` method.

    Warning: Passing just the `data` property of this class to a function may invalidate data.
  • This can be avoided by passing the whole serialize object instead.
    Examples:

Serializing a `K` object and copying the serialized data.

```python
>>> k_obj = kx.q('til 10')
>>> ser = kx.serialize(k_obj)
# The 0-copy memoryview of the data can be accessed through the `data` property
>>> ser.data
<memory at 0x7f92f05b4dc0>
# The underlying bytes can be copied with the `copy` method.
>>> k_obj_copy = ser.copy()
>>> k_obj_copy
b'\x01\x00\x00\x00^\x00\x00\x00\x07\x00\n\x00\x00...'
```

You can also directly index into the serialized object.

```python
>>> k_obj = kx.q('til 10')
>>> ser = kx.serialize(k_obj)
>>> ser[0]
1
>>> bytes(ser[0:5])
b'\x01\x00\x00\x00^'
```

copy 

copy()

Returns a copy of the bytes making up the serialized object.

Examples:

Serializing a K object and then copying the serialized data to a new variable.

>>> k_obj = kx.q('til 10')
>>> ser = kx.serialize(k_obj)
>>> k_obj_copy = ser.copy()
>>> k_obj_copy
b'\x01\x00\x00\x00^\x00\x00\x00\x07\x00\n\x00\x00...'

deserialize 

deserialize(data)

Helper method to deserialize K objects from bytes.

Parameters:

Name Type Description Default
data Union[bytes, serialize, memoryview]

The object to deserialize.

 required

Examples:

Deserialize a serialized K object.

>>> k_obj = kx.q('til 10')
>>> ser = kx.serialize(k_obj)
>>> kx.deserialize(ser)
pykx.LongVector(pykx.q('0 1 2 3 4 5 6 7 8 9'))

You can also directly deserialize a bytes object.

>>> k_obj = kx.q('til 10')
>>> ser = kx.serialize(k_obj).copy()
>>> ser
b'\x01\x00\x00\x00^\x00\x00\x00\x07\x00\n\x00\x00...'
>>> kx.deserialize(ser)
pykx.LongVector(pykx.q('0 1 2 3 4 5 6 7 8 9'))