Google Cloud CDN

How to integrate Google Cloud CDN into Limy

Forward GCP Cloud CDN Access Logs to Limy Analytics

This guide walks you through forwarding Google Cloud CDN access logs to Limy Analytics in near real-time.

Cloud CDN → Cloud Logging → Log Sink → Pub/Sub Topic → Push Subscription → Limy Analytics

Logs flow from Cloud CDN into Cloud Logging automatically. We create a pipeline that routes them to a Pub/Sub topic, which pushes each log entry to Limy Analytics ingestion endpoint within seconds.

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Prerequisites

• A GCP project with Cloud CDN and a load balancer already configured

• Cloud Logging API enabled

• Pub/Sub API enabled

• A Limy Analytics account

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Step 1: Create a Pub/Sub Topic

1. Open the Google Cloud Console

2. Navigate to Pub/Sub → Topics

3. Click Create Topic

4. Set the Topic ID to - limy-analytics-topic

5. Uncheck 'Add a default subscription'

6. Click Create

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Step 2: Create a Log Sink

The log sink routes matching log entries from Cloud Logging into the Pub/Sub topic.

1. Navigate to Logging → Log Router

2. Click Create Sink

3. Fill in the following:

Sink Details

Field	Value
Sink name	limy-analytics-sink

Click Next.

Sink Destination

Field	Value
Sink service	Cloud Pub/Sub topic
Cloud Pub/Sub topic	Select limy-analytics-topic

Click Next.

Choose Logs to Include

In the inclusion filter field, enter:

For all load balancer logs:

resource.type="http_load_balancer"

For a specific load balancer, add a filter on the forwarding rule or URL map name:

resource.type="http_load_balancer"
resource.labels.forwarding_rule_name="YOUR_FORWARDING_RULE_NAME"

or

resource.type="http_load_balancer"
resource.labels.url_map_name="YOUR_URL_MAP_NAME"

Tip: To find the exact resource label values for your load balancer, go to Logs Explorer, filter by resource.type="http_load_balancer", expand any log entry, and look under resource.labels.

For multiple load balancers, you can combine filters:

resource.type="http_load_balancer"
AND (
  (resource.labels.forwarding_rule_name="MY-FORWARDING-RULE-NAME"
  AND resource.labels.url_map_name="MY-URL-MAP-NAME")
  OR
  (resource.labels.forwarding_rule_name="MY-FORWARDING-RULE-NAME-2"
  AND resource.labels.url_map_name="MY-URL-MAP-NAME-2")
)

Click Next.

Choose Logs to Exclude (Optional)

Skip this step or add exclusion filters if needed.

1. Click Create Sink

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Step 3: Create a Push Subscription

The push subscription sends each message to Limy Analytics automatically.

1. Navigate to Pub/Sub → Topics → limy-analytics-topic

2. Click Create Subscription

3. Fill in the following:

Field	Value
Subscription ID	limy-analytics-push
Delivery type	Push
Endpoint URL	https://stream.getlimy.ai

Add a Transform

The transform injects your Limy Analytics API key into each message and removes unused fields to reduce log export volume and improve performance.

1. Click Add a Transform

2. Enter TransformGcpCdnToLimyFormat as the function name

3. Paste the following code into the function body:

function TransformGcpCdnToLimyFormat(message, metadata) {

    const data = JSON.parse(message.data);
    data['api_key'] = 'YOUR_LIMY_API_KEY';

    // remove unused fields
    delete data['insertId'];
    delete data['jsonPayload'];
    delete data['logName'];
    delete data['receiveTimestamp'];
    delete data['resource'];
    delete data['severity'];
    delete data['spanId'];
    delete data['trace'];

    message.data = JSON.stringify(data);

    return message;

}

Important: Replace YOUR_LIMY_API_KEY with your actual Limy Analytics API key.

1. Click Validate to ensure the function is valid

2. Click Create