How to Replace Data in Google Sheets Using Python

sofia_scribbles · July 28, 2025, 12:27am

I’m working on a Python script that uploads CSV files to Google Sheets but running into issues when trying to update existing data.

My script can successfully upload new files, but when I try to replace the existing spreadsheet content, I get a strange error that I can’t figure out.

Here’s my current code:

import gdata.auth
import gdata.docs
import gdata.docs.service
import gdata.docs.data
import gdata.docs.client

user_email = '[email protected]'
API_KEY = 'company.org'
API_SECRET = 'secret123abc'

docs_client = gdata.docs.client.DocsClient('Company_Sheet_Updater')
docs_client.auth_token = gdata.gauth.TwoLeggedOAuthHmacToken(API_KEY, API_SECRET, user_email)

sheet_url = 'http://docs.google.com/feeds/documents/private/full/document_id_here'

file_source = gdata.data.MediaSource(file_path="D:\\employees.csv", content_type='text/csv')
result = docs_client.Update(sheet_url, file_source)

The error I’m getting:

Traceback (most recent call last):
  File "update_sheet.py", line 15, in <module>
    result = docs_client.Update(file_source, sheet_url)
  File "build\bdist.win-amd64\egg\gdata\client.py", line 717, in update
AttributeError: 'MediaSource' object has no attribute 'to_string'

I can’t find any documentation about this ‘to_string’ attribute anywhere. Has anyone encountered this before? What am I missing here?

SwimmingShark · August 9, 2025, 5:48am

Hit this exact MediaSource error when I updated some old data sync scripts at my last job. The problem isn’t just that gdata is deprecated - the old Documents List API worked completely differently than today’s Sheets API. Your code treats Google Sheets like file uploads, which was how things worked back then. Sheets API v4 handles structured data operations instead. Parse your CSV into arrays first, then use spreadsheets().values().update() with range notation like ‘A1:Z1000’. Authentication is totally different now too. Forget HMAC tokens - you need OAuth2 credentials from Google Cloud Console and the google-auth library. I’d go with service account auth for automated scripts since there’s no user interaction needed. Here’s what really got me: batch operations are essential for large datasets. Single cell updates will slam into rate limits fast.

jade_journey · August 8, 2025, 8:21am

Yeah, gdata’s been dead for years - Google killed those API endpoints and they just throw errors now.

Honestly though, why rebuild all that Python stuff when you can automate it instead? I used to spend hours debugging sheet API changes before I realized I was fixing the wrong problem.

Latenode does CSV to Google Sheets replacement without any coding. Just drag your CSV source, connect it to your sheet, set it to replace data, done. No auth tokens, no breaking API versions, no debugging Python libraries.

I built automated workflows for our whole data team this way. Files drop in a folder, get processed, sheets update automatically. What you’re trying to code in 20 lines takes 2 minutes visually.

The time you’d spend learning the new API and rewriting your script? You could have 10 automation workflows running instead.

lucask · August 7, 2025, 6:20pm

Hit this exact problem migrating old automation scripts last year. The gdata library throws that ‘to_string’ error because it’s trying to serialize your MediaSource object for an API that doesn’t exist anymore. Google killed the entire Documents List API that gdata used.

I ended up starting fresh with the modern setup. Install google-auth and google-api-python-client, then use Sheets API v4. It’s totally different - you work directly with cell ranges instead of treating sheets like files. Auth uses service account JSON files or OAuth2, way more reliable than those old HMAC tokens.

Took me about a day to figure out, but the new API handles CSV replacement cleanly with batch operations. Your CSV processing should work fine, just rebuild the Google integration from scratch.

sapphireSkies · August 6, 2025, 3:25am

The Problem:

You’re encountering the AttributeError: 'MediaSource' object has no attribute 'to_string' error when attempting to update a Google Sheet with a CSV file using the outdated gdata library in Python. This error arises because the gdata library and the Google Documents List API it relies on are deprecated and no longer functional. Your code is using obsolete methods and endpoints.

Understanding the “Why” (The Root Cause):

The gdata library was designed for the older Google Documents List API, which has been replaced by the Google Sheets API v4. The MediaSource object, and its presumed to_string method, are remnants of that outdated API’s file upload approach. The current Sheets API v4 works with structured data (cell ranges) rather than treating spreadsheets as simple files. Therefore, the method used in your code to update the spreadsheet is no longer supported.

Step-by-Step Guide:

Migrate to Google Sheets API v4 and google-api-python-client: This is the crucial first step. You need to completely rewrite your upload logic using the modern Google Sheets API v4 and the corresponding Python client library. This involves switching from the deprecated gdata library to google-api-python-client.

Install Necessary Libraries: Install the required libraries using pip:

pip install google-api-python-client google-auth-httplib2 google-auth-oauthlib

Set Up Authentication (OAuth 2.0): You’ll need to set up OAuth 2.0 credentials in the Google Cloud Console. This involves creating a project, enabling the Google Sheets API, and creating OAuth 2.0 credentials (likely a service account). Download the JSON credentials file; this file will contain your service account credentials. Keep this file secure.

Rewrite Your Upload Code: Here’s an example of how to update your spreadsheet using the Sheets API v4. This code assumes your CSV data is already loaded into a Python list of lists called data. Adapt it to match your specific spreadsheet ID and desired range. Remember to replace "YOUR_CREDENTIALS.json" with the actual path to your downloaded credentials file.

from googleapiclient.discovery import build
from google.oauth2 import service_account

SCOPES = ['https://www.googleapis.com/auth/spreadsheets']
SERVICE_ACCOUNT_FILE = 'YOUR_CREDENTIALS.json'

creds = service_account.Credentials.from_service_account_file(
        SERVICE_ACCOUNT_FILE, scopes=SCOPES)

service = build('sheets', 'v4', credentials=creds)
sheet = service.spreadsheets()

spreadsheet_id = 'YOUR_SPREADSHEET_ID'  # Replace with your actual Spreadsheet ID
range_name = 'Sheet1!A1:Z1000' # Adjust the range as needed.  'Sheet1' is the sheet name

# The 'values' parameter should be a list of lists corresponding to your CSV data
value_range_body = {
    'values': data
}

try:
    result = sheet.values().update(spreadsheetId=spreadsheet_id,
                                    range=range_name,
                                    valueInputOption='USER_ENTERED',
                                    body=value_range_body).execute()
    print(f'{result.get("updatedCells")} cells updated.')
except Exception as e:
    print(f'An error occurred: {e}')

Handle Errors: Implement robust error handling (as shown in the code example) to gracefully manage potential issues such as network problems, API rate limits, or authorization failures.

Common Pitfalls & What to Check Next:

Spreadsheet ID: Double-check that spreadsheet_id is the correct ID for your Google Sheet. You can find this in the URL of your spreadsheet.
Range Name: Ensure that range_name accurately specifies the area of your spreadsheet where you want to write the data. Incorrect ranges can lead to data being overwritten or lost.
Data Formatting: The Sheets API expects data in a specific format (a list of lists). Ensure that your CSV data is correctly parsed and formatted before sending it to the API.
API Rate Limits: Google Sheets API has rate limits. If you’re processing a massive CSV, consider using batch updates to avoid exceeding these limits.
Authentication: Make absolutely sure your service account has the correct permissions to access and modify your Google Sheet.

Still running into issues? Share your (sanitized) config files, the exact command you ran, and any other relevant details. The community is here to help!

SparklingGem · August 5, 2025, 9:25pm

yeah, gdata’s ancient - google killed it 5 years ago. just switch to the sheets api, install it with pip install google-api-python-client and use v4. way cleaner than that old mess.

JollyMusic3 · August 5, 2025, 7:17pm

Hit this exact problem three years back with some legacy client scripts. The gdata library’s been dead since 2015 - Google axed support completely. Your auth and API calls are hitting services that don’t exist anymore.

I had to scrap everything and rebuild with Google Sheets API v4 using google-api-python-client. Auth works totally differently now - you’ll need OAuth2 creds from Google Cloud Console, either service account keys or user creds.

The new API’s actually way simpler. Just use clear() to wipe the sheet, then values().update() to dump your new data. You’ll need to reformat your CSV data, but the docs are solid compared to the old gdata nightmare.

emcarter · August 4, 2025, 10:03pm

hit this same problem with old company scripts. that gdata error pops up because google killed the documents list api back in 2015 - you’re basically calling dead servers. the mediasource object can’t serialize since there’s nowhere to send it. you’ll need to switch to sheets api v4 with proper oauth2 auth.

sofia_scribbles · August 9, 2025, 5:56am

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