RFC 0014: Volume Mount Path Configuration

Summary

Pass the project’s files directory as an environment variable to handlers instead of relying on import.meta.url inference.

Problem

The Deno handler uses import.meta.url to find sibling files, but the exact path depends on how the router mounts and imports modules. The router imports from /daemon-vol/projects/<name>/files/server.ts so import.meta.url resolves to that directory. This works but is fragile — any change to the mount structure breaks handlers.

Files to Modify

• Deno router — set env var when launching handler modules
• Documentation — update handler template to use the env var

Implementation

1. When the router imports a project’s module, set process.env.__PROJECT_DIR (or Deno.env.set) to the absolute path of the project’s files directory
2. Update the handler template/documentation to use Deno.env.get("__PROJECT_DIR") instead of new URL('.', import.meta.url).pathname
3. Keep import.meta.url as a fallback if the env var isn’t set (backward compat)

Testing & Validation Requirements

• Deploy a handler that reads Deno.env.get("__PROJECT_DIR") and serves a file from it. Verify it works.
• Deploy a handler using the old import.meta.url approach. Verify it still works (backward compat).
• Change the mount path in the router. Verify the env-var-based handler still works while the import.meta.url one breaks (demonstrating the fix).

Report Requirements

• Diff of the router code
• Updated handler template with the new approach
• Test showing both old and new approaches work