mongodb-document-versioning.py

from pymongo import MongoClient
import sys
import json
from datetime import datetime

def get_database(env, dbName):
    if env == 'local' :
        connection_string = "mongodb://localhost:27017/?readPreference=primary&appname=MongoDB%20Compass&directConnection=true&ssl=false"
        client = MongoClient(connection_string)
        return client[dbName]

# Get environment name where changes have to be effected
env = sys.argv[1]
# Get database name where changes have to be effected
dbName = sys.argv[2]
# Get collection name in which changes have to be effected
collection = sys.argv[3]
# Get search criteria (in json format) for finding the original document that needs to be updated
searchQuery = sys.argv[4]
# Get fields to be updated (in json format)
updateFields = sys.argv[5]

db = get_database(env, dbName)
document = db[collection].find_one(json.loads(searchQuery))
if document is not None:
    print("============================================================================================")
    print("Original document:", document)
    print("============================================================================================")
    
    historyDocument = document.copy()
    del historyDocument['_id']
    originId = document['_id'] 
    # Store the original document id in history collection
    historyDocument['originId'] = originId
    revision = 0
    if 'revision' in document:
        revision = document['revision']
    updatedDate = datetime.now()
    updateFields = json.loads(updateFields)
    historyDocument['revision'] = revision
    historyDocument['updatedDate'] = updatedDate
    historyDocument['updateDescription'] = updateFields
    print("============================================================================================")
    print ("History:", historyDocument)
    print("============================================================================================")
    historyCollection = collection + '_history'
    db[historyCollection].insert_one(historyDocument)

    # Increment revision number by 1 each time the document is updated
    updateFields['revision'] = revision + 1
    updateFields['updatedDate'] = updatedDate
    db[collection].update_one(json.loads(searchQuery), {"$set":updateFields})
    updatedDocument = db[collection].find_one({'_id': originId})
    print("============================================================================================")
    print("Updated document:", updatedDocument)
    print("============================================================================================")
else:
    print('Document with search query', searchQuery, 'not found in collection', collection)