Fix stderr log streaming from monitored applications#241
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The Sentinel logs server tails the stdout and stderr log files, but the
stderr terminal was created with the erlexec option [:stderr]. Since tail
always writes the followed file content to its own stdout, the stderr
file content was never captured, so stderr logs were never streamed,
stored or displayed. In addition, Host.Terminal.Server only handled
{:stdout, ...} messages, silently dropping any {:stderr, ...} data.
Both log terminals now capture :stdout (the log type is carried by the
terminal metadata) and the terminal server forwards :stderr messages the
same way as :stdout for terminals that do capture that stream.
Risk assessment:
- Impact: stderr logs become visible again in the Logs page and in the
retained log storage. No behavior change for stdout streaming.
- Blast radius: Sentinel.Logs.Server terminal creation and
Host.Terminal.Server message handling. Web terminals (tty) and the
monitor/deploy paths are untouched.
- Regression risk: low. The stderr path was delivering nothing before,
so the worst case is additional (correct) log volume in the UI and in
the retention tables.
- Rollback: revert this commit, no data or config migration involved.
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…guide (#244) * Update changelog with 0.9.5 entries and document changelog maintenance Add the missing 0.9.5 entries for the merged PRs: #239, #240, #241 and #242 as bug fixes, and #237 (CloudWatch log group retention) as an enhancement. Document the changelog maintenance rules in AGENTS.md so agents know how to add entries, and remove the outdated note that said the changelog must not be edited manually. Risk assessment: - Impact: documentation only, no runtime behavior changes. - Blast radius: CHANGELOG.md and AGENTS.md. - Regression risk: none, docs-only diff. - Rollback: revert this commit. * Updated changelog
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The Sentinel logs server tails the stdout and stderr log files, but the stderr terminal was created with the erlexec option [:stderr]. Since tail always writes the followed file content to its own stdout, the stderr file content was never captured, so stderr logs were never streamed, stored or displayed. In addition, Host.Terminal.Server only handled {:stdout, ...} messages, silently dropping any {:stderr, ...} data.
Both log terminals now capture :stdout (the log type is carried by the terminal metadata) and the terminal server forwards :stderr messages the same way as :stdout for terminals that do capture that stream.
Risk assessment:
Co-Authored-By: Claude Fable 5 noreply@anthropic.com