Add --host flag to control server bind address (#1)#3
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Postmodum37 merged 2 commits intoPostmodum37:mainfrom Mar 8, 2026
Merged
Add --host flag to control server bind address (#1)#3Postmodum37 merged 2 commits intoPostmodum37:mainfrom
Postmodum37 merged 2 commits intoPostmodum37:mainfrom
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* Initial plan * Add --host flag to bind server to custom address (e.g. 0.0.0.0) Co-authored-by: abien <[email protected]> --------- Co-authored-by: copilot-swe-agent[bot] <[email protected]> Co-authored-by: abien <[email protected]>
Postmodum37
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Mar 6, 2026
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Thanks for the PR — solves a real pain point for WSL2/container users and the implementation is clean. Two issues below.
…value Address PR review feedback: - CORS and displayHost now treat :: (IPv6) as wildcard alongside 0.0.0.0 - --host with no value warns instead of silently falling back to localhost
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Problem
When running ocwatch via bunx on WSL2 (Linux), the server binds to IPv6 by default, making it inaccessible from the Windows host browser.
Bun.serve() without an explicit hostname parameter binds to IPv6 on Linux (TCP *:50234 on IPv6), even though the Bun docs (https://bun.sh/docs/api/http) state the default is "0.0.0.0".
There is no way to fix this externally. Unlike port (which supports $BUN_PORT / $PORT env vars), Bun has no environment variable, no bunfig.toml setting, and no CLI flag to control the bind address — the hostname property must be set in code via Bun.serve() options.
Fix
This patch adds a --host
flag (defaulting to localhost) that passes the hostname property to Bun.serve(), giving users explicit control over the bind address. CORS is also adjusted accordingly — --host 0.0.0.0 sets origin: "*" since requests will come from external addresses.Usage: bunx ocwatch --host 0.0.0.0
This is relevant for anyone running ocwatch in WSL2, containers, or remote/headless environments where the default binding is not reachable.