Enable code tab docs

content/deployment/configuration/code-viewer.md

@@ -0,0 +1,96 @@
+---
+title: Code Viewer
+weight: 2
+variants: -flyte -serverless -byoc +selfmanaged
+---
+
+# Code Viewer
+The Union UI allows you to view the exact code that executed a specific task. Union securely transfers the [code bundle](../../user-guide/run-scaling/life-of-a-run.md/#phase-2-image-building) directly to your browser without routing it through the control plane.
+
+![Code Viewer](../../_static/images/deployment/configuration/code-viewer/demo.png)
+
+## Enable CORS policy on your fast registration bucket
+To support this feature securely, your bucket must allow CORS access from Union. The configuration steps vary depending on your cloud provider.
+
+{{< tabs "bucket-cors-policy" >}}
+{{< tab "AWS S3 Console" >}}
+{{< markdown >}}
+1. Open the AWS Console.
+2. Navigate to the S3 dashboard.
+3. Select your fast registration bucket. By default, this is the same as the metadata bucket configured during initial deployment.
+4. Click the **Permissions** tab and scroll to **Cross-origin resource sharing (CORS)**.
+5. Click **Edit** and enter the following policy:
+![S3 CORS Policy](../../_static/images/deployment/configuration/code-viewer/s3.png)
+```
+[
+    {
+        "AllowedHeaders": [
+            "*"
+        ],
+        "AllowedMethods": [
+            "GET",
+            "HEAD",
+        ],
+        "AllowedOrigins": [
+            "https://*.unionai.cloud"
+        ],
+        "ExposeHeaders": [
+            "ETag"
+        ],
+        "MaxAgeSeconds": 3600
+    }
+]
+```
+For more details, see the [AWS S3 CORS documentation](https://docs.aws.amazon.com/AmazonS3/latest/userguide/cors.html).
+{{< /markdown >}}
+{{< /tab >}}
+{{< tab "Google GCS" >}}
+{{< markdown >}}
+Google Cloud Storage requires CORS configuration via the command line.
+
+1. Create a `cors.json` file with the following content:
+    ```json
+    [
+        {
+        "origin": ["https://*.unionai.cloud"],
+        "method": ["HEAD", "GET"],
+        "responseHeader": ["ETag"],
+        "maxAgeSeconds": 3600
+        }
+    ]
+    ```
+2. Apply the CORS configuration to your bucket:
+    ```bash
+    gcloud storage buckets update gs://<fast_registration_bucket> --cors-file=cors.json
+    ```
+3. Verify the configuration was applied:
+   ```bash
+   gcloud storage buckets describe gs://<fast_registration_bucket> --format="default(cors_config)"
+
+   cors_config:
+   - maxAgeSeconds: 3600
+     method:
+     - GET
+     - HEAD
+     origin:
+     - https://*.unionai.cloud
+     responseHeader:
+     - ETag
+   ```
+For more details, see the [Google Cloud Storage CORS documentation](https://docs.cloud.google.com/storage/docs/using-cors#command-line).
+{{< /markdown >}}
+{{< /tab >}}
+{{< tab "Azure Storage" >}}
+{{< markdown >}}
+For Azure Storage CORS configuration, see the [Azure Storage CORS documentation](https://learn.microsoft.com/en-us/rest/api/storageservices/cross-origin-resource-sharing--cors--support-for-the-azure-storage-services).
+{{< /markdown >}}
+{{< /tab >}}
+{{< /tabs >}}
+
+## Troubleshooting
+
+| Error Message | Cause | Fix |
+|---------------|-------|-----|
+| `Not available: No code available for this action.` | The task does not have a code bundle. This occurs when the code is baked into the Docker image or the task is not a code-based task. | This is expected behavior for tasks without code bundles. |
+| `Not Found: The code bundle file could not be found. This may be due to your organization's data retention policy.` | The code bundle was deleted from the bucket, likely due to a retention policy. | Review your fast registration bucket's retention policy settings. |
+| `Error: Code download is blocked by your storage bucket's configuration. Please contact your administrator to enable access.` | CORS is not configured on the bucket. | Configure CORS on your bucket using the instructions above. |