JSON匯入

1. 開啟Collection

import json
import pymongo

client = pymongo.MongoClient('localhost')
db = client['mydb']
collection = db['images']

2.開啟json並寫入到Collection

str = open("e:/images.json", encoding="utf-8").read()
data = []
data.extend(json.loads(str))
collection.insert_many(data)
client.close() #寫完關閉連線
 

JSON匯出

1.開啟Collection

import json
import pymongo
import re

client = pymongo.MongoClient('localhost')
db = client['mydb']
collection = db['images']

2.查詢讀取Colleciton

output = []
for i in collection.find():
    output.append(i)

3.處理id問題
one=output[0]

因為collection.find()得到的欄位_id是自動生成的ObjectId
ObjectId

one.get('_id').__repr__()
#輸出
"ObjectId('5bfb49544d37b935a4a82eca')"
#使用正則表示式取出12位元組的id
re.findall("'(.*)'",one.get('_id').__repr__())[0]
'5bfb49544d37b935a4a82eca'
 

4.根據(3)方法修改所有id

for i in range(len(data)):
    output[i]['_id'] = re.findall("'(.*)'", output[i].get('_id').__repr__())[0]

也可以在讀取時修改

output = []
for i in collection.find():
    i['_id']=re.findall("'(.*)'",i.get('_id').__repr__())[0]
    output.append(i)

5.寫入到json檔案

with open('d:/images.json', 'w', encoding="UTF-8") as jf:
    jf.write(json.dumps(output, indent=2))

json.dumps(output,indent)將每一項dict轉換為str,避免了直接寫入時因為未序列化而報錯,同時指定縮排字元個數indent為2

p.s.
順帶一提,在adminMongo中,點選Collection旁邊的Export即可匯出json

可以勾選是否匯出_id欄位