relsandbox

A basic Erlang OTP app used for testing release and appup tooling.

Build and Run

$ rebar3 compile
$ ./start.sh

Versions and Upgrades

Using the following git tags, move between versions to test upgrades etc.

NB: I don't care about downgrades, and probably won't be testing them.

v1

Basic app with supervisor, one gen_server that counts with get/inc api.

v2 v1...v2

Add a decrement convenience function, no #state{} change.

Expected .appup

{"2",
    [{"1", [
        {load_module, relsandbox_counter}
    ]}],
    [{"1", [
        {load_module, relsandbox_counter}
    ]}]
}.

v3 v2...v3

Add name field to #state{} and get/set API. This requires a code_change function to upgrade the state record.

Expected .appup

{"3",
    [{"2", [
        {update, relsandbox_counter, {advanced, []}}
    ]}],
    [{"2", [
        {update, relsandbox_counter, {advanced, []}}
    ]}]
}.

v4 v3...v4

Add a new module, relsandbox_phonebook with get/set API. This requires a new child to be started under relsandbox_sup

Also add a boring utility module, relsandbox_boring.

Expected .appup

{"4",
    [{"3", [
        {load_module, relsandbox_boring},
        {load_module, relsandbox_phonebook},
        {update, relsandbox_sup, supervisor},
        {apply, {supervisor, restart_child, [relsandbox_sup, relsandbox_phonebook]}}
    ]}],
    [{"3", [
        {apply, {supervisor, terminate_child, [relsandbox_sup, relsandbox_phonebook]}},
        {apply, {supervisor, delete_child,    [relsandbox_sup, relsandbox_phonebook]}},
        {update, relsandbox_sup, supervisor},
        {delete_module, relsandbox_phonebook},
        {delete_module, relsandbox_boring}
    ]}]
}.

v5 v4...v5

Remove module, relsandbox_boring. Add dependency on lager (no appup instructions needed for this).

Expected .appup

{"5",
    [{"4", [
        {delete_module, relsandbox_boring}
    ]}],
    [{"4", [
        {load_module, relsandbox_boring}
    ]}]
}.