This example demonstrates how to test Volcano Realtime capabilities from within a function.

Realtime Function Test

This example demonstrates how to test Volcano Realtime capabilities from within a function.

What This Tests

Connection - Connects to the Volcano Realtime server
Broadcast Channels - Subscribes and sends messages
Presence Channels - Tracks user presence
Postgres Changes - Subscribes to database change events
RLS Isolation - Verifies users only receive their own data

Security Focus

This test specifically validates Row-Level Security (RLS) isolation:

Creates a test table with RLS policies
Inserts records for the current user
Verifies the user receives change events for their own records
Inserts records for a different user
Verifies the user does NOT receive change events for other users' records

This is critical for multi-tenant applications where data isolation is essential.

Deployment

# From this example's directory
cd realtime-function-test
npm install
zip -r function.zip .

# Deploy using Volcano CLI or API
volcano functions deploy realtime-test --file function.zip

Environment Variables

Set these in your Volcano project:

Variable	Description
`VOLCANO_API_URL`	The Volcano API server URL
`VOLCANO_ANON_KEY`	Your project's anon key
`VOLCANO_REALTIME_URL`	(Optional) Realtime WebSocket URL

Invocation

This function requires an authenticated user context:

Invoke the invoke_url the API returns for the function rather than building a host, which differs between deployments:

INVOKE_URL=$(curl -s "$VOLCANO_API_URL/projects/$PROJECT_ID/functions/$FUNCTION_ID" \
  -H "Authorization: Bearer $PLATFORM_TOKEN" | jq -r '.invoke_url')

# Invoke with user authentication
curl -X POST "$INVOKE_URL" \
  -H "Authorization: Bearer YOUR_ACCESS_TOKEN" \
  -H "Content-Type: application/json"

Expected Output

{
  "success": true,
  "summary": "6 passed, 0 failed",
  "tests": [
    { "name": "Connection", "passed": true },
    { "name": "Broadcast Subscribe", "passed": true },
    { "name": "Broadcast Send", "passed": true },
    { "name": "Presence Channel", "passed": true },
    { "name": "Postgres Subscribe", "passed": true },
    { "name": "Postgres Change Received", "passed": true },
    { "name": "RLS Isolation", "passed": true },
    { "name": "Disconnect", "passed": true }
  ],
  "errors": []
}

RLS Policy Setup

For the RLS isolation test to work, your database table needs proper RLS policies:

-- Enable RLS on your table
ALTER TABLE your_table ENABLE ROW LEVEL SECURITY;

-- Create a policy that uses the JWT claim
CREATE POLICY user_isolation ON your_table
  FOR ALL
  USING (user_id::text = current_setting('request.jwt.claim.sub', true));

The request.jwt.claim.sub setting is automatically set by Volcano when authenticating database connections, ensuring that RLS policies can identify the current user.

Realtime Function Test

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