Added tests and readme

internal/config/cluster_test.go

@@ -0,0 +1,107 @@
+package config
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestQuorumSize(t *testing.T) {
+	cases := []struct {
+		peers int
+		want  int
+	}{
+		{0, 1},
+		{1, 1},
+		{2, 2},
+		{3, 2},
+		{4, 3},
+		{5, 3},
+		{7, 4},
+	}
+	for _, tc := range cases {
+		c := &ClusterConfig{}
+		for i := 0; i < tc.peers; i++ {
+			c.Peers = append(c.Peers, PeerInfo{NodeID: fmt.Sprintf("n%d", i)})
+		}
+		if got := c.QuorumSize(); got != tc.want {
+			t.Errorf("peers=%d: QuorumSize=%d want %d", tc.peers, got, tc.want)
+		}
+	}
+}
+
+func TestClusterMutateBumpsVersion(t *testing.T) {
+	t.Setenv("QUPTIME_DIR", t.TempDir())
+	c := &ClusterConfig{}
+
+	err := c.Mutate("nodeA", func(cc *ClusterConfig) error {
+		cc.Checks = append(cc.Checks, Check{ID: "1", Name: "x"})
+		return nil
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if c.Version != 1 {
+		t.Errorf("Version=%d want 1", c.Version)
+	}
+	if c.UpdatedBy != "nodeA" {
+		t.Errorf("UpdatedBy=%q want nodeA", c.UpdatedBy)
+	}
+
+	err = c.Mutate("nodeB", func(cc *ClusterConfig) error { return nil })
+	if err != nil {
+		t.Fatal(err)
+	}
+	if c.Version != 2 {
+		t.Errorf("Version=%d want 2 after second mutate", c.Version)
+	}
+}
+
+func TestClusterReplaceGatesOnVersion(t *testing.T) {
+	t.Setenv("QUPTIME_DIR", t.TempDir())
+	cur := &ClusterConfig{Version: 5, Checks: []Check{{ID: "old"}}}
+
+	if applied, _ := cur.Replace(&ClusterConfig{Version: 4}); applied {
+		t.Error("older version was applied")
+	}
+	if applied, _ := cur.Replace(&ClusterConfig{Version: 5}); applied {
+		t.Error("equal version was applied")
+	}
+	applied, err := cur.Replace(&ClusterConfig{
+		Version: 6,
+		Checks:  []Check{{ID: "new"}},
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+	if !applied {
+		t.Error("newer version was not applied")
+	}
+	if cur.Version != 6 || len(cur.Checks) != 1 || cur.Checks[0].ID != "new" {
+		t.Errorf("after replace: %+v", cur)
+	}
+}
+
+func TestClusterSnapshotIsCopy(t *testing.T) {
+	c := &ClusterConfig{Checks: []Check{{ID: "a"}}}
+	snap := c.Snapshot()
+	snap.Checks[0].ID = "b"
+	if c.Checks[0].ID != "a" {
+		t.Error("snapshot mutation leaked back to original")
+	}
+}
+
+func TestFindAlert(t *testing.T) {
+	c := &ClusterConfig{Alerts: []Alert{
+		{ID: "id-1", Name: "primary", Type: AlertSMTP},
+		{ID: "id-2", Name: "secondary", Type: AlertDiscord},
+	}}
+	if a := c.FindAlert("primary"); a == nil || a.Type != AlertSMTP {
+		t.Errorf("by name: %+v", a)
+	}
+	if a := c.FindAlert("id-2"); a == nil || a.Type != AlertDiscord {
+		t.Errorf("by id: %+v", a)
+	}
+	if a := c.FindAlert("ghost"); a != nil {
+		t.Errorf("expected nil for missing, got %+v", a)
+	}
+}