feat: initial release

internal/roles/master/master.go

@@ -0,0 +1,93 @@
+package master
+
+import (
+	"context"
+	"sync"
+
+	"git.wzray.com/homelab/mastermind/internal/config"
+	"git.wzray.com/homelab/mastermind/internal/roles"
+	"git.wzray.com/homelab/mastermind/internal/state"
+	"git.wzray.com/homelab/mastermind/internal/types"
+	"git.wzray.com/homelab/mastermind/internal/web/client"
+)
+
+type Role struct {
+	state      *state.RuntimeState
+	config     config.MasterConfig
+	tasksGroup sync.WaitGroup
+	observer   *observer
+	roles.BaseRole
+}
+
+func New(state *state.RuntimeState, config config.MasterConfig) *Role {
+	return &Role{
+		state:  state,
+		config: config,
+		observer: newObserver(
+			state,
+			config.ObserverInterval,
+			config.BackoffSeconds,
+			config.BackoffCount,
+		),
+	}
+}
+
+func (r *Role) OnStartup(ctx context.Context) error {
+	r.tasksGroup.Go(func() {
+		r.observer.Start(ctx, func(n types.Node) error {
+			_, err := r.onLeave(n)
+			return err
+		})
+	})
+
+	return nil
+}
+
+func (r *Role) OnShutdown() error {
+	r.tasksGroup.Wait()
+	return nil
+}
+
+func (r *Role) notify(path types.Path, v any) {
+	for _, n := range r.state.Registry.Nodes() {
+		addr := n.Address
+		r.tasksGroup.Go(func() {
+			client.Post[any](addr, path, v)
+		})
+	}
+}
+
+func (r *Role) onJoin(node types.Node) ([]types.Node, error) {
+	if err := r.state.Registry.AddNode(node); err != nil {
+		return nil, err
+	}
+
+	r.notify(types.PathNodeJoin, node)
+
+	return r.state.Registry.AllNodes(), nil
+}
+
+func (r *Role) onLeave(node types.Node) (bool, error) {
+	if err := r.state.Registry.RemoveNode(node.Name); err != nil {
+		return false, err
+	}
+
+	r.notify(types.PathNodeLeave, node.Name)
+
+	return true, nil
+}
+
+func (r *Role) onKeepAlive(node types.Node) (bool, error) {
+	if ok := r.state.Registry.Exists(node.Name); !ok {
+		_, err := r.onJoin(node)
+		return true, err
+	}
+
+	return false, nil
+}
+
+func (c *Role) RegisterHandlers(r types.Registrator) {
+	r.Register(types.PostEndpoint(types.PathMasterJoin, c.onJoin))
+	r.Register(types.PostEndpoint(types.PathMasterLeave, c.onLeave))
+	r.Register(types.PostEndpoint(types.PathMasterKeepalive, c.onKeepAlive))
+}