Deploy over SSH¶

syslet has no SSH logic of its own: you send it specs through ssh, either as a stream on stdin or as files already on the host. Both need SSH public-key auth to the host.

Pipe specs to the host¶

Pipe spec files straight into syslet --stdin, with no extra tooling and one round-trip:

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# Deploy a directory of specs
cat hosts/web01/*.json | ssh web01 sudo syslet --stdin

# Dry-run: show what would change without applying
cat hosts/web01/*.json | ssh web01 sudo syslet --diff --stdin

--stdin accepts a JSON array, newline-delimited JSON, or concatenated JSON objects: exactly what cat dir/*.json produces.

On apply (not --diff), the received stream is persisted to /etc/syslet/config.json as the host's on-disk record, so it can be re-applied later without re-sending it:

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ssh web01 sudo syslet            # re-apply /etc/syslet/config.json
ssh web01 sudo syslet --diff     # dry-run against the persisted config

Deploy from a directory on the host¶

syslet also reads a directory of .json spec files directly, which suits specs copied or checked out onto the host:

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scp -r hosts/web01/ web01:/etc/syslet/hosts/web01/
ssh web01 sudo syslet /etc/syslet/hosts/web01/

Each .json file in the directory is loaded as one spec; other files and subdirectories are ignored.

Applying from a directory or file path doesn't write /etc/syslet/config.json. The directory you pass is itself the on-disk record.