doc: add instructions for compiling cephadm

Now that cephadm is based on zipapp, add a short section to the
developer docs explaining how to build cephadm yourself.

Note: This commit is a cherry-pick of
9ad38033cc5c7f177cb8fe3bae696682687e0346, which was introduced by John
Mulligan in #48180. This is one of three commits introduced in that PR,
and this cherry-pick cleans up omissions I (Zac Dover) inadvertently
introduced while attempting to rectify the merge conflicts in #51843. I
expect that one more cherry-picked commit (specifically,
d11cf0e82aab8d4cef9d423e5d463a373eaf383a, which cannot be merged easily
until d7921e88d69b4bc355da9c0327cc33e59e7d7abb has been merged into
main, for reasons that are too
Rick-and-Morty-there-should-never-be-more-than-one-dot to go into here)
will follow this one.

Signed-off-by: John Mulligan <jmulligan@redhat.com>
(cherry picked from commit 9ad38033cc5c7f177cb8fe3bae696682687e0346)
(cherry picked from commit 421147f97c8a21272a52b5f13340c1019b0165c5)

diff --git a/doc/dev/cephadm/developing-cephadm.rst b/doc/dev/cephadm/developing-cephadm.rst
index fe6abf4ee31842c97f8052d4718c944ab24b8f28..7d2187766b1ebaf68d44d01cb2d5121ac37bb2c6 100644 (file)
--- a/doc/dev/cephadm/developing-cephadm.rst
+++ b/doc/dev/cephadm/developing-cephadm.rst
@@ -388,3 +388,16 @@ Note regarding different variables used in the code
 * a ``daemon_id`` is typically ``<service_id>.<hostname>.<random-string>``.
   (Not the case for e.g. OSDs. OSDs are always called OSD.N)
 * a ``daemon_name`` is ``<daemon_type>.<daemon_id>``
+
+.. _compiling-cephadm:
+
+Compiling cephadm
+=================
+
+Recent versions of cephadm are based on `Python Zip Application`_ support, and
+are "compiled" from Python source code files in the ceph tree. To create your
+own copy of the cephadm "binary" use the script located at
+``src/cephadm/build.py`` in the Ceph tree.  The command should take the form
+``./src/cephadm/build.py [output]``.
+
+.. _Python Zip Application: https://peps.python.org/pep-0441/