Actions runbook
Live log tail
Step log pages open an SSE stream at:
/{owner}/{repo}/actions/runs/{run}/jobs/{job}/steps/{step}/log/stream
The stream sends event: chunk records with the chunk sequence as the SSE
id. Browsers reconnect with Last-Event-ID; the handler also accepts
?after=<seq> for the first connection from a rendered log page. A terminal
step sends event: done and closes the stream.
Log chunks are never sent through Postgres NOTIFY. Runner log writes append
to workflow_step_log_chunks, then NOTIFY step_log_<step_id> with only the
sequence number. Step completion notifies done.
Rate limit
Live tails use internal/ratelimit scope actions:logtail with five
concurrent streams per viewer. Authenticated viewers key by user id; anonymous
public-repo viewers key by client IP. The limiter uses a short lease TTL so a
dropped connection cannot hold a slot permanently.
Caddy
The production Caddy template has a dedicated Actions log-stream route with:
flush_interval -1
The same route is excluded from gzip compression. If logs arrive only after
several kilobytes accumulate, verify the deployed /etc/caddy/Caddyfile
contains that route and reload Caddy:
sudo caddy reload --config /etc/caddy/Caddyfile
View source
| 1 | # Actions runbook |
| 2 | |
| 3 | ## Live log tail |
| 4 | |
| 5 | Step log pages open an SSE stream at: |
| 6 | |
| 7 | ```text |
| 8 | /{owner}/{repo}/actions/runs/{run}/jobs/{job}/steps/{step}/log/stream |
| 9 | ``` |
| 10 | |
| 11 | The stream sends `event: chunk` records with the chunk sequence as the SSE |
| 12 | `id`. Browsers reconnect with `Last-Event-ID`; the handler also accepts |
| 13 | `?after=<seq>` for the first connection from a rendered log page. A terminal |
| 14 | step sends `event: done` and closes the stream. |
| 15 | |
| 16 | Log chunks are never sent through Postgres `NOTIFY`. Runner log writes append |
| 17 | to `workflow_step_log_chunks`, then `NOTIFY step_log_<step_id>` with only the |
| 18 | sequence number. Step completion notifies `done`. |
| 19 | |
| 20 | ## Rate limit |
| 21 | |
| 22 | Live tails use `internal/ratelimit` scope `actions:logtail` with five |
| 23 | concurrent streams per viewer. Authenticated viewers key by user id; anonymous |
| 24 | public-repo viewers key by client IP. The limiter uses a short lease TTL so a |
| 25 | dropped connection cannot hold a slot permanently. |
| 26 | |
| 27 | ## Caddy |
| 28 | |
| 29 | The production Caddy template has a dedicated Actions log-stream route with: |
| 30 | |
| 31 | ```caddy |
| 32 | flush_interval -1 |
| 33 | ``` |
| 34 | |
| 35 | The same route is excluded from gzip compression. If logs arrive only after |
| 36 | several kilobytes accumulate, verify the deployed `/etc/caddy/Caddyfile` |
| 37 | contains that route and reload Caddy: |
| 38 | |
| 39 | ```sh |
| 40 | sudo caddy reload --config /etc/caddy/Caddyfile |
| 41 | ``` |