Why Does Tilt’s Live Update Stop When Non-Synced Files Change but Still Rebuild the Image?

Below is an explanation of what’s happening and why Tilt behaves in this manner.

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What’s Happening

• Your docker_build call sets the build context to "../../". This means Tilt is watching all files in that directory tree.

• The ignore parameter causes Tilt to exclude the listed directories from the build context that is sent to Docker when the image is built. However, it does not remove them from being watched for changes.

• Your live update step has a sync rule only for the ../../api_server directory. When you change a file in the deployment directory (which lies inside "../../" but is not part of any sync rule), Tilt detects that change.

• Since the changed file (e.g., deployment/dev/cluster.yaml) isn’t covered by any sync rule, Tilt stops live update for that run and falls back to a full rebuild of the image. The message

  LiveUpdate "api-server-deployment:api-server" UpdateStopped: Found file(s) not matching any sync (files: [deployment/dev/cluster.yaml])
  

  confirms this behavior.

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Why It’s Working as Designed

Tilt’s current design is such that:

• Ignore in docker_build: This only applies to what gets sent to the Docker build context, not to what triggers live update or rebuilds.
• LiveUpdate Triggers: When a file changes that is not explicitly synced (or excluded from the file watching), Tilt considers that a “missed” change that cannot be live updated. It then requires a rebuild to ensure that any changes in the build context are integrated into the image.

This means that if a change happens in a directory that is ignored for Docker context purposes but still falls under the overall build context root (in your case "../../"), Tilt will trigger a full rebuild unless it’s synced.

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How to Work Around This

If you want changes in the deployment repository not to trigger a rebuild, you have a couple of options:

1. Narrow the Build Context
   Instead of setting the build context to "../../", narrow it down so that directories like deployment and ui aren’t included at all. For example, if possible, use a build context that points just to the api_server directory or another subset of files.

   PYTHONCopied
   docker_build(
       'org/api-server',
       path='../../api_server',  # New, narrower build context
       build_args={
           "UID": UID,
           "GID": GID,
       },
       dockerfile='../deployment/local/images/api_server.dockerfile',  # Adjust if needed
       live_update=[sync('.', '/var/www/html')],
   )

2. Move Directories Outside the Build Context
   If it’s feasible for your project layout, reorganize your repositories so that the deployment repository isn’t inside the build context directory.

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Summary

Tilt is behaving as intended: even though you ignore the deployment directory for build context purposes, it still watches for changes there. When a file outside your sync rules changes, Tilt stops the live update and triggers a full rebuild. Adjusting the build context or reorganizing your repository structure are two paths to avoid unnecessary rebuilds when files in deployment change.

Let me know if you have any other questions or need further clarification!