Merge pull request #25 from rabbitmq/gen-batch-server-24

Upgrade to match modern `gen_server` (continuation of #24)

Author: michaelklishin

.github/workflows/ci.yaml

@@ -0,0 +1,31 @@
+name: CI
+on:
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        otp: ['26', '27', '28']
+    steps:
+      - uses: actions/checkout@v6
+      - uses: erlef/setup-beam@v1
+        with:
+          otp-version: ${{ matrix.otp }}
+          rebar3-version: '3.24'
+      - uses: actions/cache@v4
+        with:
+          path: |
+            _build
+            ~/.cache/rebar3
+          key: ${{ runner.os }}-otp-${{ matrix.otp }}-rebar3-${{ hashFiles('rebar.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-otp-${{ matrix.otp }}-rebar3-
+      - run: epmd -daemon
+      - run: rebar3 ct --sname batch_test
+      - run: rebar3 dialyzer
+      - run: rebar3 xref

README.md

@@ -89,14 +89,27 @@ The timeout is optional and defaults to 5000ms.
 
     Types:
         Args = term()
-        Result = {ok, State} | {stop, Reason}
-        State = term(),
+        Result = {ok, State} |
+                 {ok, State, {continue, Continue}} |
+                 ignore |
+                 {stop, Reason}
+        State = term()
+        Continue = term()
         Reason = term()
 
-
 Called whenever a `gen_batch_server` is started with the arguments provided
 to `start_link/4`.
 
+Returning `{ok, State, {continue, Continue}}` will cause `handle_continue/2`
+to be called before processing any messages.
+
+Returning `ignore` will cause `start_link` to return `ignore` and the process
+will exit normally without a crash report.
+
+Can be used in scenarios where a `gen_batch_server`
+depends on a resource that can be temporarily
+unavailable (e.g. when a Ra member runs out of disk space).
+
 #### Module:handle_batch(Batch, State) -> Result.
 
     Types:
@@ -105,7 +118,11 @@ to `start_link/4`.
         Op = {cast, UserOp} |
              {call, from(), UserOp} |
              {info, UserOp}.
-        Result = {ok, State} | {ok, Actions, State} | {stop, Reason}
+        Result = {ok, State} |
+                 {ok, State, {continue, Continue}} |
+                 {ok, Actions, State} |
+                 {ok, Actions, State, {continue, Continue}} |
+                 {stop, Reason}
         State = term()
         From = {Pid :: pid(), Tag :: reference()}
         Action = {reply, From, Msg} | garbage_collect
@@ -115,6 +132,24 @@ to `start_link/4`.
 Called whenever a new batch is ready for processing. The implementation can
 optionally return a list of reply actions used to reply to `call` operations.
 
+#### Module:handle_continue(Continue, State) -> Result
+
+    Types:
+        Continue = term()
+        State = term()
+        Result = {ok, NewState} |
+                 {ok, NewState, {continue, NewContinue}} |
+                 {stop, Reason}
+        NewState = term()
+        NewContinue = term()
+        Reason = term()
+
+Optional. Called after `init/1` returns `{ok, State, {continue, Continue}}` or
+after `handle_batch/2` returns with a `{continue, Continue}` tuple.
+
+Most useful for post-`init/2` work that needs
+the server to be registered first.
+
 #### Module:terminate(Reason, State) -> Result
 
     Types:
@@ -138,4 +173,3 @@ Optional. Used to provide a custom formatting of the user state.
 # Copyright
 
 (c) 2018-2023 Broadcom. All Rights Reserved. The term Broadcom refers to Broadcom Inc. and/or its subsidiaries.
-

rebar.config

@@ -1,4 +1,4 @@
-{minimum_otp_vsn, "22.3"}.
+{minimum_otp_vsn, "26"}.
 {deps, []}.
 {project_plugins, [rebar3_hex]}.
 {profiles,

src/gen_batch_server.app.src

@@ -3,7 +3,7 @@
               {licenses,["Apache-2.0","MPL-2.0"]},
               {links,[{"github",
                        "https://github.com/rabbitmq/gen-batch-server"}]},
-              {vsn,"0.8.9"},
+              {vsn,"0.9.0"},
               {modules,[gen_batch_server]},
               {registered,[]},
               {applications,[kernel,stdlib]},