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How to serialize custom class objects in JSON? - Exsul1 - Sep-19-2019
The Python documentation on JSON reads, "This simple serialization technique can handle lists and dictionaries, but serializing arbitrary class instances in JSON requires a bit of extra effort. The reference for the json module contains an explanation of this." But I can't seem to find the explanation in the JSON reference. I'm very new to programming, so it's probably there; it just went right over my head.
The reason I need to serialize the objects of a class I created is that I'm making a random NPC generator for tabletop RPGs, and each generated NPC is an instance of my NPC class with semi-randomized characteristics. Users will want to save the ones they like.
So how does one serialize a custom class object with JSON?
Thanks in advance.
RE: How to serialize custom class objects in JSON? - Larz60+ - Sep-20-2019
google 'arbitrary class instance in JSON python'
RE: How to serialize custom class objects in JSON? - ndc85430 - Sep-22-2019
In essence, it just boils down to making a JSON object where the keys are the field names (and so the values are, well, the field values). If you can make a dictionary in that form, you can just use
json.dumps to produce a string containing the JSON representation.
RE: How to serialize custom class objects in JSON? - Exsul1 - Sep-22-2019
(Sep-22-2019, 06:26 PM)ndc85430 Wrote: In essence, it just boils down to making a JSON object where the keys are the field names (and so the values are, well, the field values). If you can make a dictionary in that form, you can just use json.dumps to produce a string containing the JSON representation.That's basically what I ended up doing, except I used a list instead of a dictionary:
def append_to_file(npc):
"""Append the attributes of an NPC to save file as a JSON string"""
# Pull the attributes off an NPC class instance
attrib_list = [npc.sex, npc.char, npc.principles, npc.law_disposition,
npc.trait1_type, npc.trait2_type, npc.trait1, npc.trait2,
npc.conf_ct1, npc.conf_ct2, npc.conf_tt, npc.quirk,
npc.prof_type, npc.prof, npc.con, npc.ill, npc.looks]
# Open (or create) the save file in append mode
with open("saved_npcs.txt", "a") as save_file:
# Serializing attribute list to save file
# as a JSON-formatted string
save_file.write(json.dumps(attrib_list))
save_file.write("\n")
RE: How to serialize custom class objects in JSON? - wavic - Sep-23-2019
Hello!
Look at jasonpickle module.