macula-testkit

In-memory test support for macula consumers. Run the real macula pub/sub stack in-process, with no QUIC, no certificates, and no station.

It provides a drop-in loopback pool (mem_macula): a gen_server that speaks the macula_client pool protocol, so macula:publish(Pool, ...) and macula:subscribe(Pool, ...) work unchanged against an in-memory mesh. A publish on one pool reaches subscribers on any pool in the cluster.

Pub/sub only. RPC, advertise and streaming answer {error, unsupported}.

It mirrors the command-side pattern: evoq -> mem-evoq -> evoq-testkit becomes macula -> macula-testkit (mem_macula) -> consumers.

The pool is the real seam, not the transport plugin. The SDK pub/sub path is hardcoded to QUIC below the pool (macula_peering_conn), so an in-memory macula_net_transport would not make macula:publish/subscribe work; the pool gen_server protocol is where the in-memory swap lives. See the proposal for the full finding.

{ok, #{pools := [A, B]} = Cluster} = mem_macula:cluster(2),
{ok, _Ref} = macula:subscribe(B, Realm, Topic, self()),
ok = macula:publish(A, Realm, Topic, Fact),
%% self() receives {macula_event, _, Topic, Fact, _}
ok = mem_macula:stop(Cluster).

Skips are failures: cth_skip_is_failure

rebar3 ct exits 0 when a case skips itself, so a suite whose tests never ran reads as green. This Common Test hook turns every skip nobody allowed into a failure. Switch it on in rebar.config, and allow each wanted skip with the reason it is safe:

{ct_opts, [{ct_hooks, [{cth_skip_is_failure,
    [{allow, [{my_SUITE, a_case, "why skipping it here is safe"},
              {dist_SUITE, '*', "needs distribution; run by ct_dist.sh"}]}]}]}]}.

The second element names the case, or '*' for any skip in that suite, including its init_per_suite and init_per_group. An allowance without a reason stops the run before it starts. The hook needs only OTP's common_test.

Install

The library has no dependencies; bring your own macula (12.x) for mem_macula, usually in the test profile:

{profiles, [{test, [{deps, [{macula_testkit, "~> 0.2"}]}]}]}.

Status

Pub/sub is proved against the real macula 12 facade by this repo's suite. The design and the finding behind the pool seam are in PROPOSAL_MACULA_TESTKIT.md. macula-services/mcl-testkit composes this into the mcl_om service-boot path for the mcl-* services.

License

Apache-2.0. See LICENSE.