Seamlessly Integrating AWS S3 with SharePoint for Enterprise File Management

Organizations rely heavily on AWS S3 for scalable storage and SharePoint for collaborative workflows. Synchronizing these platforms boosts productivity by unifying file access and governance across cloud environments.

Forget the hype around rewrites and costly migrations—discover how a straightforward integration strategy can unify your storage and collaboration seamlessly, eliminating data silos without disrupting your users.

Why Integrate AWS S3 with SharePoint?

AWS S3 is an industrial-strength, cost-effective object storage service popular for storing vast amounts of unstructured data. Meanwhile, SharePoint thrives as a collaboration platform where teams manage documents, track projects, and share knowledge.

However, many enterprises find themselves juggling these two silos: centralized storage on S3 but fragmented access via disparate SharePoint libraries — leading to inefficiencies, version confusion, and governance headaches.

Integrating S3 with SharePoint enables:

Unified access: End users find all files within their familiar SharePoint interface.
Governance consistency: Apply compliance policies and permissions in one place.
Improved workflows: Automate document updates and metadata syncing.
Cost savings: Avoid duplicating storage or migrating gigabytes of data.

Approaches to Integrating AWS S3 with SharePoint

While a rewrite or full migration sounds tempting, it’s often costly and disruptive — especially if you have terabytes of data or existing integrations relying on either platform.

A practical integration achieves synchronization or real-time access without moving everything physically.

Here are common methods:

Using Third-Party Connectors

Several third-party tools—like Cloud FastPath, AvePoint, or SkySync—offer ready-made connectors syncing files between S3 buckets and SharePoint libraries. They handle metadata mapping, incremental syncs, and conflict resolution.

Pros: Quick implementation, minimal coding
Cons: Licensing costs, limited customization
Custom Middleware with AWS Lambda and Microsoft Graph API

Build a lightweight service that listens to new/updated uploads in an S3 bucket (via S3 event notifications), then programmatically replicates those files into corresponding SharePoint libraries using the Microsoft Graph API.

Pros: Highly customizable workflows, no recurring fees
Cons: Requires development effort, ongoing maintenance
Leveraging Azure Logic Apps or Power Automate

Connect AWS S3 triggers to SharePoint actions through drag-and-drop workflows. For example, when a new file lands in your S3 bucket, it automatically copies to a SharePoint folder with assigned metadata.

Pros: Low-code solution, quick prototype
Cons: Can become complex for large-scale syncing

Step-by-Step Example: Sync New Files from AWS S3 to SharePoint Using AWS Lambda + Microsoft Graph API

Let’s walk through a practical example using option #2 above—ideal for teams comfortable with scripting but wanting tight control over sync behavior without third-party costs.

Prerequisites:

An existing AWS S3 bucket
A Microsoft 365 tenant with access to SharePoint Online and Azure AD App registration
Basic knowledge of Python or Node.js

Step 1: Set Up Azure AD App Registration to Access Microsoft Graph API

In the Azure Portal, register a new app under Azure Active Directory.
Assign delegated permissions for Microsoft Graph:
- Files.ReadWrite.All
- Sites.ReadWrite.All
Generate a client secret and note down:
- Application (client) ID
- Directory (tenant) ID
- Client secret value

Step 2: Create an AWS Lambda Function Triggered by S3 Events

import json
import boto3
import requests

# Constants from Azure AD app
TENANT_ID = 'your-tenant-id'
CLIENT_ID = 'your-client-id'
CLIENT_SECRET = 'your-client-secret'

# Target SharePoint site & library info
SHAREPOINT_SITE_ID = 'your-sharepoint-site-id'
SHAREPOINT_DRIVE_ID = 'your-document-library-drive-id'

def get_access_token():
    url = f"https://login.microsoftonline.com/{TENANT_ID}/oauth2/v2.0/token"
    payload = {
        'grant_type': 'client_credentials',
        'client_id': CLIENT_ID,
        'client_secret': CLIENT_SECRET,
        'scope': 'https://graph.microsoft.com/.default'
    }
    r = requests.post(url, data=payload)
    r.raise_for_status()
    return r.json()['access_token']

def upload_file_to_sharepoint(access_token, file_name, file_content):
    endpoint = f"https://graph.microsoft.com/v1.0/sites/{SHAREPOINT_SITE_ID}/drives/{SHAREPOINT_DRIVE_ID}/root:/{file_name}:/content"
    headers = {'Authorization': f'Bearer {access_token}', 'Content-Type': 'application/octet-stream'}
    r = requests.put(endpoint, headers=headers, data=file_content)
    r.raise_for_status()
    print(f"Uploaded {file_name} to SharePoint successfully.")

def lambda_handler(event, context):
    s3_client = boto3.client('s3')
    access_token = get_access_token()

    for record in event['Records']:
        bucket_name = record['s3']['bucket']['name']
        object_key = record['s3']['object']['key']

        # Download file from S3
        obj = s3_client.get_object(Bucket=bucket_name, Key=object_key)
        file_content = obj['Body'].read()

        # Upload to SharePoint
        upload_file_to_sharepoint(access_token, object_key.split('/')[-1], file_content)

    return {
        'statusCode': 200,
        'body': json.dumps('S3 files synced to SharePoint successfully.')
    }

Step 3: Configure S3 Event Notifications

In the AWS Console for your bucket:
- Go to Properties > Event notifications.
- Add a notification on PUT (object created) events targeting your Lambda function.

What Happens Next?

Whenever someone uploads or modifies a file in your designated S3 bucket:

The event triggers the Lambda function.
The function retrieves the new/updated file content.
It authenticates with Microsoft Graph using the Azure AD App credentials.
Uploads the file directly into your chosen SharePoint Document Library folder.

This flow ensures near real-time sync from AWS S3 storage into collaborating teams’ familiar space inside SharePoint — no manual uploads needed!

Best Practices When Syncing Between AWS S3 & SharePoint

Plan your folder structure carefully so it aligns well in both platforms minimizing complex path mapping.
Use metadata tags consistently in both systems; consider adding properties during upload via Graph API if needed.
Monitor logs & error reports from Lambda executions or third-party connectors regularly.
Look into incremental sync techniques or change detection if handling very large datasets.
Secure credentials carefully—use secrets managers wherever possible instead of plain text in code.

Conclusion

Integrating AWS S3 with SharePoint doesn’t have to be a disruptive migration nightmare nor require expensive proprietary gateways. By leveraging native APIs alongside serverless functions or automation tools like Power Automate you can build efficient bridges connecting scalable cloud storage with productive collaboration platforms — empowering users while maintaining enterprise-grade governance.

Give this real-world integration approach a try; unlock seamless document flows between Amazon’s powerful object store and your organization’s collaboration hub today!

S3 To Sharepoint