Python 3 & jsonpickle module
==============================
I this post I will show how save data (Eg. TOP 10 Game Scores and Usernames in Object format) in JSON format and after in a text-file.json in your drive.
https://jsonpickle.github.io/
https://pypi.org/project/jsonpickle/
DOWNLOAD INDENTED CODE FREE HERE FROM MY AWS S3
https://lse-blogs.s3-eu-west-1.amazonaws.com/personal/highscores-json-pickle.zip
highscores-json-pickle.py
import json
import jsonpickle
class GameEntry:
“””Represents one entry of a list of high scores.”””
def __init__(self, name, score):
“””Create an entry with given name and score.”””
self._name = name
self._score = score
def get_name(self):
“””Return the name of the person for this entry.”””
return self._name
def get_score(self):
“””Return the score of this entry.”””
return self._score
def __str__(self):
“””Return string representation of the entry.”””
return ‘({0}, {1})’.format(self._name, self._score) # e.g., ‘(Bob, 98)’
class Scoreboard:
“””Fixed-length sequence of high scores in nondecreasing order.”””
def __init__(self, capacity=10):
“””Initialize scoreboard with given maximum capacity.
All entries are initially None.
“””
self._board = [None] * capacity # reserve space for future scores
self._n = 0 # number of actual entries
def __getitem__(self, k):
“””Return entry at index k.”””
return self._board[k]
def __str__(self):
“””Return string representation of the high score list.”””
return ‘\n’.join(str(self._board[j]) for j in range(self._n))
def add(self, entry):
“””Consider adding entry to high scores.”””
score = entry.get_score()
# Does new entry qualify as a high score?
# answer is yes if board not full or score is higher than last entry
good = self._n < len(self._board) or score > self._board[-1].get_score()
if good:
if self._n < len(self._board): # no score drops from list
self._n += 1 # so overall number increases
# shift lower scores rightward to make room for new entry
j = self._n – 1
while j > 0 and self._board[j-1].get_score() < score:
self._board[j] = self._board[j-1] # shift entry from j-1 to j
j -= 1 # and decrement j
self._board[j] = entry # when done, add new entry
def deserialize(fileName):
# From disk
with open(fileName) as j:
frozen_obj = jsonpickle.decode(j.read())
return frozen_obj
def serialize(fileName, frozen):
# To disk
with open(fileName, ‘w’) as j_out:
print(frozen, file=j_out)
if __name__ == ‘__main__’:
board = Scoreboard()
# Load Prior players scores
for e in (
(‘Rob’, 750), (‘Mike’,1105), (‘Rose’, 590), (‘Jill’, 740),
(‘Jack’, 510), (‘Anna’, 660), (‘Paul’, 720), (‘Bob’, 400),
):
ge = GameEntry(e[0], e[1])
board.add(ge)
frozen = jsonpickle.encode(board)
serialize(“hightscores.json”, frozen)
boardNew = deserialize(“hightscores.json”)
# Load current player score
p = (“Player9”, 2999)
ge = GameEntry(p[0], p[1])
boardNew.add(ge)
frozenNew = jsonpickle.encode(boardNew)
serialize(“hightscores.json”, frozenNew)
hightscores.json
{"_board": [{"_name": "Player9", "_score": 2999, "py/object": "__main__.GameEntry"}, {"_name": "Mike", "_score": 1105, "py/object": "__main__.GameEntry"}, {"_name": "Rob", "_score": 750, "py/object": "__main__.GameEntry"}, {"_name": "Jill", "_score": 740, "py/object": "__main__.GameEntry"}, {"_name": "Paul", "_score": 720, "py/object": "__main__.GameEntry"}, {"_name": "Anna", "_score": 660, "py/object": "__main__.GameEntry"}, {"_name": "Rose", "_score": 590, "py/object": "__main__.GameEntry"}, {"_name": "Jack", "_score": 510, "py/object": "__main__.GameEntry"}, {"_name": "Bob", "_score": 400, "py/object": "__main__.GameEntry"}, null], "_n": 9, "py/object": "__main__.Scoreboard"}
