mesh-controller/internal/catalogue/backup_placement_test.go

package catalogue

import (
	"reflect"
	"strings"
	"testing"
)

// A machine's backup lines are placement (design 57 L3, issue 794): the holder of node-backup names them as
// `${backup:lines}` and `${backup:data}`, which a handed holder has its client fill from the plan and an unhanded
// one has the controller fill as it fills `${contribution:node-backup:backup}` and `${...:data}`: the same text.

const (
	oldBackupText   = "# lines\n${contribution:node-backup:backup}"
	oldDataText     = "# data\n${contribution:node-backup:data}"
	placedBackupTxt = "# lines\n${backup:lines}"
	placedDataTxt   = "# data\n${backup:data}"
	backupHolder    = `{"module":"restic","version":"1","moved":true,"claims":[{"name":"node-backup","scope":"node"}],
  "build":{"artifacts":[{"name":"files","kind":"archive","from":"files"}]},
  "resources":[{"id":"declared","type":"file","path":"/etc/backups.conf","template":"files/backups"},
               {"id":"data-declared","type":"file","path":"/etc/data.conf","template":"files/data"}]}`
)

func dataModule(name string) string {
	return `{"module":"` + name + `","version":"1","resources":[{"id":"d","type":"directory","mode":"0700"}],
  "data":{"own":[{"id":"d","path":"${dir:d}","class":"irreplaceable","why":"the ` + name + ` data"}]}}`
}

// backupsOn is a machine of a holder whose files say these texts and the modules that declare data.
func backupsOn(t *testing.T, lines, data string, modules ...string) Resolution {
	t.Helper()
	all := []Manifest{held(t, backupHolder, builtWith("restic", map[string]string{"backups": lines, "data": data}))}
	names := []string{"restic"}
	for _, name := range modules {
		all = append(all, mustParse(t, dataModule(name)))
		names = append(names, name)
	}
	r, err := Resolve(shelf(all...), names, workstation(), World{})
	if err != nil {
		t.Fatal(err)
	}
	r.Account = "op"
	return r
}

var backupModules = []string{"alpha", "beta", "gamma"}

// gammaLeftOut is a machine whose gamma does not place: its lines are kept, best effort.
func gammaLeftOut(with Rendering) Rendering {
	with.NotPlaced = map[string]string{"gamma": "its placement setting does not read"}
	return with
}

func TestTheBackupPlacementIsTheTextTheOldPlaceholdersRender(t *testing.T) {
	// The old form is an unmoved holder: its placeholders are the controller's alone.
	oldHolder := strings.Replace(backupHolder, `"moved":true,`, "", 1)
	all := []Manifest{held(t, oldHolder, builtWith("restic", map[string]string{"backups": oldBackupText, "data": oldDataText}))}
	for _, name := range backupModules {
		all = append(all, mustParse(t, dataModule(name)))
	}
	old, err := Resolve(shelf(all...), append([]string{"restic"}, backupModules...), workstation(), World{})
	if err != nil {
		t.Fatal(err)
	}
	old.Account = "op"
	wantLines, wantData := fileOf(t, old, gammaLeftOut(Rendering{}), "restic.declared"), fileOf(t, old, gammaLeftOut(Rendering{}), "restic.data-declared")
	if !strings.Contains(wantLines, "# alpha\npath ") || !strings.Contains(wantLines, "# gamma\n") || !strings.Contains(wantData, "item d") {
		t.Fatalf("the old form renders\n%s\n%s", wantLines, wantData)
	}
	moved := backupsOn(t, placedBackupTxt, placedDataTxt, backupModules...)
	// Not handed: the controller fills the new placeholders with the old text.
	if got := fileOf(t, moved, gammaLeftOut(Rendering{}), "restic.declared"); got != wantLines {
		t.Errorf("not handed, the lines are\n%s\nwant\n%s", got, wantLines)
	}
	if got := fileOf(t, moved, gammaLeftOut(Rendering{}), "restic.data-declared"); got != wantData {
		t.Errorf("not handed, the data is\n%s\nwant\n%s", got, wantData)
	}
	// Handed: the plan carries the same text as placement, and the files are the client's.
	c, _ := composeWith(t, moved, gammaLeftOut(handingTo("store:5000")))
	p := c.Plans["restic"].Placement
	if got := "# lines\n" + p["backup:lines"]; got != wantLines {
		t.Errorf("handed, the plan's lines are\n%s\nwant\n%s", got, wantLines)
	}
	if got := "# data\n" + p["backup:data"]; got != wantData {
		t.Errorf("handed, the plan's data is\n%s\nwant\n%s", got, wantData)
	}
	if len(p) != 2 {
		t.Errorf("the plan's placement is %v", p)
	}
}

func TestAModuleAddedOrTakenAwayChangesTheBackupPlan(t *testing.T) {
	plan := func(modules ...string) map[string]string {
		c, _ := composeWith(t, backupsOn(t, placedBackupTxt, placedDataTxt, modules...), handingTo("store:5000"))
		return c.Plans["restic"].Placement
	}
	two, three := plan("alpha", "beta"), plan("alpha", "beta", "gamma")
	if reflect.DeepEqual(two, three) || strings.Contains(two["backup:lines"], "gamma") || !strings.Contains(three["backup:lines"], "# gamma\n") {
		t.Errorf("two modules give %v, three give %v", two, three)
	}
}

func TestAnUnknownBackupKeyIsRefused(t *testing.T) {
	r := backupsOn(t, "${backup:rows}", placedDataTxt, backupModules...)
	if _, err := r.Compose(handingTo("store:5000")); err == nil || !strings.Contains(err.Error(), "backup:rows") {
		t.Errorf("handed, an unknown key is %v", err)
	}
	if _, err := r.Declaration(Rendering{}); err == nil || !strings.Contains(err.Error(), "backup:rows") {
		t.Errorf("not handed, an unknown key is %v", err)
	}
}

func fileOf(t *testing.T, r Resolution, with Rendering, id string) string {
	t.Helper()
	out, err := r.Declaration(with)
	if err != nil {
		t.Fatal(err)
	}
	for _, res := range out {
		if res["id"] == id {
			return res["content"].(string)
		}
	}
	t.Fatalf("%s was not composed", id)
	return ""
}