Automate Document Approvals with Multi-Level Workflows using Supabase & Gmail

Multi-Level Document Approval & Audit Workflow

This workflow automates a document approval process using Supabase and Gmail.

Who it’s for Teams that need structured multi-level document approvals.
Companies managing policies, contracts, or proposals. Medical document need multiple lavel of review and approval.

How it works Form Trigger – A user submits a document via the form.
Supabase Integration – The document is saved in the documents table.
Supabase Storage – The document is saved in the bucket. Workflow Levels – Fetches the correct approval level from workflow_levels.
Assign Approvers – Matches approvers by role from the users table.
Approval Record – Creates an approvals record with a unique token and expiry.
Email Notification – Sends an email with Approve / Reject links.
Audit Logs – Records every approval request in audit_logs. Repeat - repeat the flow till all the aproval level is comepted

How to set up Configure your Supabase credentials. Create tables as per data model given. Create a storage bucket in Supabase Storage. Connect your Gmail account.
Adjust approval expiry time (48h default).
Deploy and test via the Form Trigger.
Customization Add multiple approval levels by chaining workflow_levels.
Replace Gmail with Slack, Teams, or another notification channel.
Adjust audit logging for compliance needs.
Update the endpoint http://localhost:5678/webhook-test/ based on instance and env (remove test if you run in prod) Update the bucket name.

Important steps

1. Form Submit Triggered when by submiting form Captures form parameters:
   Title (Document Title)
   Description (Document Description) file (Document need for approval)

2. Webhook Entry Point Triggered when an approver clicks the Approve or Reject link in email.
   Captures query parameters:
   token (approval token)
   decision (approved/rejected)

3. Approval Data Retrieval & Update Fetch approval record from Supabase (approvals) using token.
   Update approval status:
   Approved → moves to next workflow level or final approval.
   Rejected → document marked as rejected immediately.
   Records acted_at timestamp.

4. Decision Check IF Node* checks whether the decision is approved or rejected*.
   Reject Path* → Update document status to Rejected* in documents.
   Approve Path** → Continue workflow level progression.

5. Workflow Level Progression Fetch details of the current workflow level.
   Identify the next level (workflow_levels) based on level_number.

✅ If Next Level Exists: Retrieve approvers by role_id.
Generate unique approval tokens.
Create new approval records in approvals.
Send email notifications with approval/reject links.

❌ If No Next Level (Last Level): Update document status to Approved in documents.

6. Audit Logging Every approval action is logged into audit_logs table:
   document_id
   action (e.g., approval_sent, approved, rejected)
   actor_email (system/approver)
   details (workflow level, role info, etc.)

📨 Email Template Approval request email includes decision links:

Please review the document:

✅ Approve | ❌ Reject

Happy Automating! 🚀