To further support OTP releases I have added support for generating
application appup files. These include instructions that systools uses
to generate a relup file which contains the low level instructions
needed to perform a hot code upgrade. My goal with this module is to
produce "good enough" appup files or at least a skeleton to help one get
started with something more complex. If an appup file already exists for
an application this command will not attempt to create a new one.
Usage:
$ rebar generate-appups previous_release=/path/to/old/version
Generally this command will be run just before 'generate-upgrade'.
To support OTP release upgrades I have added support for building
upgrade packages. Support for this is included in the
rebar_upgrade module, specifically generate_upgrade/2. It requires
one variable to be set on the command line 'previous_release' which
is the absolute path or relative path from 'rel/' to the previous
release one is upgrading from. Running an upgrade will create the
needed files, including a relup and result in a tarball containing
the upgrade being written to 'rel/'. When done it cleans up the
temporary files systools created.
Usage:
$ rebar generate-upgrade previous_release=/path/to/old/version
This also includes a dummy application that can be used to test
upgrades as well as an example.
Special thanks to Daniel Reverri, Jesper Louis Andersen and
Richard Jones for comments and patches.
