Symptom

WinterCG runtime limitations prevent the direct fetching of dynamic data from Contentstack entries within a Launch Edge Function, causing failures when attempting to avoid hardcoded URLs in proxy configurations.

Root Cause

Launch Edge Functions operate within a restricted runtime environment that does not support the direct execution of certain SDK queries or external fetches intended for complex dynamic data retrieval.

Resolution

To handle dynamic URL routing or data retrieval within an Edge Function, implement the following workaround:

1. Create an API Route: Develop a Next.js API route at the origin to fetch the required data from Contentstack using the JavaScript SDK.
2. Consume Data in Edge Function: Configure the Edge Function to call the internal API route rather than querying the CMS directly.
3. Optimize with Caching: Apply cache-control headers to the API response to improve performance and reduce origin load.
4. Implement Revalidation: Utilize Contentstack Automate to trigger cache revalidation, ensuring the Edge Function has access to the most recent data without constant fetching.

Verification

The issue is resolved when the Edge Function successfully retrieves dynamic URLs through the intermediary API route without encountering runtime failures.

Symptom

Setting up Live Preview in Astro projects may fail when environment variables are handled incorrectly during SSR or SSG. This prevents users from viewing real-time content changes within the Live Preview interface.

Root Cause

Environment variables in Contentstack Launch are parsed upon ingestion, whereas local development environments typically treat these variables strictly as string values, leading to configuration mismatches.

Resolution

1. Navigate to your Astro project configuration and verify how environment variables are being accessed for SSR and SSG.
2. Adjust your code to account for the fact that Launch parses environment variables rather than treating them solely as strings.
3. Review the implementation guide for Astro to ensure the Live Preview integration aligns with platform requirements.

Verification

After completing the resolution steps, open the Contentstack entry editor and initiate a Live Preview session for your Astro project. If the preview renders correctly and reflects your content changes, the issue is resolved.

Symptom

A custom field application hosted on Launch fails to load within the Contentstack editor, displaying a Content Security Policy (CSP) error. This occurs because the browser refuses to frame the application URL, citing that an ancestor violates the frame-ancestors 'self' directive, particularly when users access the application via a VPN.

Root Cause

The application lacks a server-side framework (such as Next.js or Express) to modify response headers directly. By default, the CSP headers restrict the application from being embedded (framed) in external sites like the Contentstack UI.

Resolution

1. Create a folder named functions at the root of your project.
2. Inside this folder, add a file named [proxy].edge.js.
3. Implement a handler function within [proxy].edge.js to modify the response headers.
4. Use the Edge Function to explicitly set or update the Content Security Policy headers to allow the application to be embedded within Contentstack.
5. Deploy the project; Contentstack Launch will automatically detect the new functions folder and apply the header modifications to all requests.
6. If further clarification is needed on the function implementation, a technical call can be scheduled with the support team.

Verification

After the deployment is complete, navigate to the Contentstack entry that utilizes the custom field application. If the custom field application loads successfully within the Contentstack UI without being blocked by CSP restrictions, the issue is resolved.

Symptom

Deploying an Elasticsearch adapter via a webhook in Launch can result in 404 errors. While converting the adapter to an Edge Function may provide an immediate workaround, it introduces potential stability concerns due to runtime compatibility requirements.

Root Cause

Launch Edge Functions require code to be WinterCG-compliant. Some adapters or third-party libraries may not fully support this standard, leading to unexpected behavior or limited functionality during execution.

Resolution

1. Use Launch Cloud Functions instead of Edge Functions for adapters that require a more robust Node.js environment or lack WinterCG compliance.
2. Alternatively, implement a dedicated route within your application framework to handle the adapter's logic directly.
3. Ensure that any code run within an Edge Function environment is verified for compatibility with the WinterCG standard.

Verification

Trigger the webhook or adapter logic and verify the response status. The issue is resolved when the 404 error is replaced by a successful data exchange and the function executes successfully in the logs.