Serializing YAML with PyYAML: Difference between revisions
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==Constructor== | ==Constructor== | ||
A constructor allows you to take a serialized YAML node and return a class instance. | |||
==Representer== | ==Representer== |
Revision as of 23:13, 7 December 2022
Internal
Overview
The process of serialization to YAML is rendering an in-memory data structure as a YAML-formatted string. The simplest sequence of statements that does that is:
import yaml
data = {
'color': 'red',
'size': 10,
'parts': ['top', 'middle', 'bottom']
}
yaml_string = yaml.dump(data)
The YAML-formatted string will be:
color: red
parts:
- top
- middle
- bottom
size: 10
How PyYAML Serialization Works
PyYAML core model is centered on constructors, representers and tags.
Constructor
A constructor allows you to take a serialized YAML node and return a class instance.
Representer
A representer is a function that serializes a class instance to a YAML node representation. The representer gets a Dumper
instance as a first argument, and the data object as the second. The function must return the serialized representation of the data object instance, as a s string.
def my_representer(dumper, data):
The representers are registered with add_representer()
. Representers can be added for specific types (such as str
or int
), or for ???
yaml.add_representer(str, my_representer)