cluster: rework env output to qualify zones using the region

Signed-off-by: Alejandro Mery <amery@jpi.io>

go.mod

@@ -4,7 +4,7 @@ go 1.19
 
 require (
 	asciigoat.org/ini v0.2.5
-	darvaza.org/core v0.14.0
+	darvaza.org/core v0.14.1
 	darvaza.org/resolver v0.9.2
 	darvaza.org/sidecar v0.4.0
 	darvaza.org/slog v0.5.7

go.sum

@@ -4,8 +4,8 @@ asciigoat.org/ini v0.2.5 h1:4gRIp9rU+XQt8+HMqZO5R7GavMv9Yl2+N+je6djDIAE=
 asciigoat.org/ini v0.2.5/go.mod h1:gmXzJ9XFqf1NLk5nQkj04USQ4tMtdRJHNQX6vp3DzjU=
 darvaza.org/cache/x/simplelru v0.1.8 h1:rvFucut4wKYbsYc994yR3P0M08NqlsvZxr5G4QK82tw=
 darvaza.org/cache/x/simplelru v0.1.8/go.mod h1:Mv1isOJTcXYK+aK0AvUe+/3KpRTXDsYga6rdTS/upNs=
-darvaza.org/core v0.14.0 h1:DzvPjfob0QuRgLjVkNt3Fq5Wbx9uE/AHVcYVEbGQQk8=
-darvaza.org/core v0.14.0/go.mod h1:C+B0GRNLB+/asGfxjQ9XZERdk7xaFxzt5xTIBPiNm2M=
+darvaza.org/core v0.14.1 h1:PJXoG4u5gMx8G3zs7VcAIN6bmWTi1yp8vpuikPvDucQ=
+darvaza.org/core v0.14.1/go.mod h1:C+B0GRNLB+/asGfxjQ9XZERdk7xaFxzt5xTIBPiNm2M=
 darvaza.org/resolver v0.9.2 h1:sUX6LZ1eN5TzJW7L4m7HM+BvwBeWl8dYYDGVSe+AIhk=
 darvaza.org/resolver v0.9.2/go.mod h1:XWqPhrxoOKNzRuSozOwmE1M6QVqQL28jEdxylnIO8Nw=
 darvaza.org/sidecar v0.4.0 h1:wHghxzLsiT82WDBBUf34aTqtOvRBg4UbxVIJgKNXRVA=

pkg/cluster/env.go

@@ -4,6 +4,7 @@ import (
 	"bytes"
 	"fmt"
 	"io"
+	"sort"
 	"strings"
 
 	"darvaza.org/core"
@@ -53,7 +54,23 @@ func (m *Env) Zones(r *Region) []rings.ZoneID {
 	return zones
 }
 
-// Regions returns the list of primary regions
+// RegionsNames returns a sorted list of primary regions names
+func (m *Env) RegionsNames() []string {
+	var regions []string
+
+	m.ForEachRegion(func(r *Region) bool {
+		if r.IsPrimary() {
+			regions = append(regions, r.Name)
+		}
+
+		return false
+	})
+
+	sort.Strings(regions)
+	return regions
+}
+
+// Regions returns a sorted list of primary regions IDs
 func (m *Env) Regions() (regions []rings.RegionID) {
 	m.ForEachRegion(func(r *Region) bool {
 		if r.IsPrimary() {
@@ -75,18 +92,38 @@ func (m *Env) WriteTo(w io.Writer) (int64, error) {
 		m.writeEnvVar(&buf, m.cephFSID, "FSID")
 	}
 
-	m.writeEnvVar(&buf, genEnvInts(m.Regions()), "REGIONS")
-
-	m.ForEachRegion(func(r *Region) bool {
-		if r.IsPrimary() {
-			m.writeEnvRegion(&buf, r)
-		}
-		return false
+	regions := m.getRegions()
+	ids := core.SliceMap(regions, func(_ []rings.RegionID, r *Region) (out []rings.RegionID) {
+		return append(out, r.ID)
 	})
+	names := core.SliceMap(regions, func(_ []string, r *Region) (out []string) {
+		return append(out, r.Name)
+	})
+
+	m.writeEnvVar(&buf, genEnvInts(ids), "REGIONS")
+	m.writeEnvVar(&buf, genEnvStrings(names), "REGIONS_NAMES")
+
+	for _, r := range regions {
+		m.writeEnvRegion(&buf, r)
+	}
 
 	return buf.WriteTo(w)
 }
 
+func (m *Env) getRegions() (out []*Region) {
+	m.ForEachRegion(func(r *Region) bool {
+		if r.IsPrimary() {
+			out = append(out, r)
+		}
+		return false
+	})
+
+	core.SliceSort(out, func(a, b *Region) int {
+		return cmpOrdered(a.ID, b.ID)
+	})
+
+	return out
+}
 func (m *Env) writeEnvRegion(w io.Writer, r *Region) {
 	regionID := r.ID