This fixes a regression introduced in commit a2ef2bcbfd7 ("machine: hetzner:
Allow connections using ssh-agent"), where having no ssh-key would cause the
early Hetzner provisioning to fail due to the lack of SSH authentication.
* gnu/machine/hetzner.scm (%hetzner-ssh-key-file): New parameter.
(<hetzner-configuration>) [ssh-public-key]: Compute default according to the
value of the private ssh-key field. Introduce an indirection via...
(hetzner-configuration-ssh-public-key): ... this new procedure, to honor
%hetzner-ssh-key-file.
(hetzner-configuration-ssh-key): Likewise for the private ssh-key.
(hetzner-configuration-ssh-key-fingerprint): Rename to...
(public-key->fingerprint): ... this, taking just the public key as argument.
Update doc.
(hetzner-configuration-ssh-key-public): Rename to...
(public-key->string-with-type): ...this, for clarity, and accept just a
public-key object. Update doc.
(hetzner-machine-ssh-key): Exit early with #f when no ssh key is provided.
(temporary-ssh-key-file): New procedure.
(hetzner-machine-ssh-key-create): Assert a public key is defined. Adjust
calls to renamed procedures, and adjust for the `hetzner-api-server-create'
API change.
(hetzner-machine-enable-rescue-system): Refine doc and fix code path when
ssh-key is #f.
(hetzner-machine-rescue-install-os): Document.
(hetzner-machine-provision): Refine doc. Remove extraneous sleep and #:unwind
argument. Limit ssh-session dynamic scope to where it's needed.
(cleanup-temporary-ssh-key/maybe): New procedure.
(deploy-hetzner): Create and use a temporary SSH key when none is defined, and
clean it up when done or on errors.
* gnu/machine/hetzner/http.scm (hetzner-api-server-create): Make ssh-keys a
keyword argument, and fix execution when it's #f.
(hetzner-api-server-enable-rescue-system): Likewise.
* tests/machine/hetzner.scm ("deploy-machine-mock-with-unprovisioned-server"):
Adjust test.
* tests/machine/hetzner/http.scm (create-server)
("hetzner-api-server-create-unit")
("hetzner-api-server-enable-rescue-system-unit")
("hetzner-api-actions-integration")
("hetzner-api-server-enable-rescue-system-integration"): Likewise.
* doc/guix.texi (Invoking guix deploy): Precise what happens when 'ssh-key' is
#f in hetzner-configuration, and suggest declaratively authorizing your SSH
key.
Change-Id: I812b348fb553f3b5aebd0bf66850c6ecb9e06653