core: wip combine SWIM's infection style with Raft's leader election …

…algo

Dockerfile

@@ -1,11 +1,9 @@
-FROM debian:bookworm
-RUN set -x && apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y curl xz-utils ca-certificates && rm -rf /var/lib/apt/lists/*
+FROM kassany/alpine-ziglang:0.13.0
 WORKDIR /tmp/
 COPY src/ ./src/
 COPY build* ./
-RUN curl -O https://ziglang.org/download/0.13.0/zig-linux-x86_64-0.13.0.tar.xz && \
-xz --decompress zig-linux-x86_64-0.13.0.tar.xz && tar -xf zig-linux-x86_64-0.13.0.tar && \
-./zig-linux-x86_64-0.13.0/zig build -Doptimize=ReleaseFast --summary all
+# RUN zig build -Doptimize=ReleaseFast --summary all
+RUN zig build --summary all
 
 FROM debian:stable-slim
 RUN set -x && apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y curl ca-certificates && rm -rf /var/lib/apt/lists/*

deployment.yaml

@@ -0,0 +1,55 @@
+---
+
+apiVersion: apps/v1
+kind: Deployment
+metadata:
+  name: zgroup
+spec:
+  selector:
+    matchLabels:
+      app: zgroup
+  replicas: 1
+  revisionHistoryLimit: 5
+  template:
+    metadata:
+      labels:
+        app: zgroup
+    spec:
+      containers:
+      - name: zgroup
+        image: asia.gcr.io/mobingi-main/zgroup:v39
+        command: ["/bin/sh"]
+        args: ["-c", '/app/zgroup group1 ${K8S_MY_POD_IP}:8080']
+        resources:
+          requests:
+            cpu: 100m
+            memory: 500Mi
+          limits:
+            cpu: 100m
+            memory: 500Mi
+        imagePullPolicy: Always
+        env:
+        # Downward value to know if we are running in k8s.
+        - name: K8S_MY_POD_IP
+          valueFrom:
+            fieldRef:
+              fieldPath: status.podIP
+        - name: GET_HOSTS_FROM
+          value: dns
+        ports:
+        - containerPort: 8080
+
+---
+
+apiVersion: autoscaling/v1
+kind: HorizontalPodAutoscaler
+metadata:
+  name: zgroup-hpa
+spec:
+  scaleTargetRef:
+    apiVersion: apps/v1
+    kind: Deployment
+    name: zgroup
+  minReplicas: 3
+  maxReplicas: 3
+  targetCPUUtilizationPercentage: 40

dockerfile-debian

@@ -0,0 +1,15 @@
+FROM debian:bookworm
+RUN set -x && apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y curl xz-utils ca-certificates && rm -rf /var/lib/apt/lists/*
+WORKDIR /tmp/
+COPY src/ ./src/
+COPY build* ./
+RUN curl -O https://ziglang.org/download/0.13.0/zig-linux-x86_64-0.13.0.tar.xz && \
+xz --decompress zig-linux-x86_64-0.13.0.tar.xz && tar -xf zig-linux-x86_64-0.13.0.tar && \
+./zig-linux-x86_64-0.13.0/zig build -Doptimize=ReleaseFast --summary all
+
+FROM debian:stable-slim
+RUN set -x && apt-get update && DEBIAN_FRONTEND=noninteractive apt-get install -y curl ca-certificates && rm -rf /var/lib/apt/lists/*
+WORKDIR /app/
+COPY --from=0 /tmp/zig-out/bin/zgroup .
+ENTRYPOINT ["/app/zgroup"]
+CMD ["group1", "0.0.0.0:8080"]

localbuild.sh

@@ -0,0 +1,6 @@
+kubectl delete -f deployment.yaml
+docker build --rm -t zgroup .
+docker tag zgroup asia.gcr.io/mobingi-main/zgroup:$1
+docker push asia.gcr.io/mobingi-main/zgroup:$1
+docker rmi $(docker images --filter "dangling=true" -q --no-trunc) -f
+sed -i -e 's/image\:\ asia.gcr.io\/mobingi\-main\/zgroup[\:@].*$/image\:\ asia.gcr.io\/mobingi\-main\/zgroup\:'$1'/g' deployment.yaml

src/main.zig

@@ -169,7 +169,7 @@ fn setJoinAddress(allocator: std.mem.Allocator, group: []const u8, addr: []const
     defer allocator.free(buf);
     const out = enc.encode(buf, addr);
 
-    log.info("callback: leader={s}, set join info to {s}", .{ addr, out });
+    log.info("callback: join={s}, set join info to {s}", .{ addr, out });
 
     const url = try std.fmt.allocPrint(
         allocator,

src/scratch.zig

@@ -179,12 +179,21 @@ test "accesslen" {
     dbg("len={d}\n", .{buf.len});
 }
 
-test "defercont" {
-    var i: usize = 0;
-    while (true) : (i += 1) {
-        defer dbg("[{d}] defer here\n", .{i});
-        if (i == 10) continue;
-        if (i == 20) break;
-        defer dbg("[{d}] todo\n", .{i});
+test "comp" {
+    var empty = try std.fmt.allocPrint(std.testing.allocator, "", .{});
+    dbg("len_empty={d}\n", .{empty.len});
+    const str = try std.fmt.allocPrint(std.testing.allocator, "hello", .{});
+    defer std.testing.allocator.free(str);
+    empty = str;
+    dbg("len_empty={d}\n", .{empty.len});
+}
+
+test "defer" {
+    var b = false;
+    defer {
+        if (b) dbg("captured\n", .{});
     }
+
+    std.time.sleep(std.time.ns_per_s);
+    b = false;
 }