feat: probe an app certificate by its fingerprint - #549
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josegonzalez merged 2 commits intoSep 18, 2026
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josegonzalez merged 2 commits into
josegonzalez merged 2 commits into
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dokku 0.38.28 adds `--ssl-fingerprint` and `--ssl-serial` to `certs:report` via dokku/dokku#8996, which the `dokku_certs` probe reads to compare an installed certificate without transferring it.
`dokku_certs` read the whole certificate back with `certs:show` on every plan to decide whether the pinned one was already installed, moving certificate material off the server purely to answer a yes-or-no question. dokku 0.38.28 carries the SHA-256 digest of the installed certificate on `certs:report`, so an app is now settled against a digest taken locally and the certificate stays where it is. A recipe pinning a certificate chain keeps the exact comparison, since dokku digests only the leaf, and so does the global certificate, whose plugin reports no fingerprint.
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September 18, 2026 02:47
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dokku_certsdecided whether the pinned certificate was already installed by reading the whole certificate back withcerts:showon every plan, which moved certificate material off the server purely to answer a yes-or-no question, on a command whose other argument hands back the private key. dokku 0.38.28 carries the SHA-256 digest of the installed certificate oncerts:reportvia dokku/dokku#8996, so an app is now settled against a digest taken locally from the pinned PEM and the certificate itself stays where it is. The task's documented dokku floor moves to 0.38.28 with it.dokku takes that digest with
openssl x509 -in server.crt, which reads the leaf and ignores the rest, so a recipe pinning a certificate chain keeps the exact comparison rather than quietly narrowing to its first certificate; a rotated intermediate under an unchanged leaf is still drift. The global certificate keeps it too, sincedokku-global-certcomputes a fingerprint internally but exposes none on its report. A value that is not a digest, or a dokku that reports none at all, falls back to the same comparison, so nothing converges less well than it did before.Closes #529