Python script to migrate one Arguflow instance to another using postgres of origin instance only

arguflow_migrate_server.py

import psycopg2
from dotenv import load_dotenv
import os
import json
import requests

# Load the .env file
load_dotenv()
api_key = os.environ.get("API_KEY")
api_url = os.environ.get("API_URL")
origin_db_url = os.environ.get("ORIGIN_DB_URL")

class Card:
    def __init__(self, card_html, tag_set, tracking_id, metadata_dict):
        self.card_html = card_html
        self.tag_set = tag_set
        self.tracking_id = tracking_id
        self.metadata = metadata_dict
        if not self.metadata:
            print("Missing metadata.")
            exit(1)

    def to_json(self):
        def replace_nan_none(obj):
            if isinstance(obj, float) and (obj != obj or obj is None):
                return ""
            if obj is None:
                return ""
            if isinstance(obj, dict):
                return {key: replace_nan_none(value) for key, value in obj.items()}
            if isinstance(obj, list):
                return [replace_nan_none(item) for item in obj]
            return obj

        json_dict = {
            key: replace_nan_none(value) for key, value in self.__dict__.items()
        }

        return json.dumps(json_dict, sort_keys=True, default=str)

    def send_post_request(self):
        url = f"{api_url}/card"

        payload = self.to_json()

        headers = {"Content-Type": "application/json", "Authorization": api_key}
        req_result = requests.post(url, data=payload, headers=headers)

        if req_result.status_code != 200:
            req_error = req_result.text
            print(req_error)

conn = psycopg2.connect(origin_db_url)
cur = conn.cursor()

cur.execute("SELECT DISTINCT ON (metadata) * FROM card_metadata")

while True:
    # Fetch 20 rows
    rows = cur.fetchmany(20)

    # If no more rows are available, break the loop
    if not rows:
        break

    # Iterate over the rows
    for row in rows:
        # Access the payload and update the corresponding qdrant point
        card_html = row[8] if row[8] is not None else ""
        tag_set = row[7] if row[7] is not None else ""
        tracking_id = row[12] if row[12] is not None else ""
        metadata = row[11] if row[11] is not None else ""

        card = Card(card_html, tag_set, tracking_id, metadata)
        card.send_post_request()

# Close the cursor and connection
cur.close()
conn.close()