mesh-controller/internal/catalogue/holds_test.go

package catalogue

import (
	"encoding/json"
	"strings"
	"testing"
)

// novox/hq ADR 0377 §3: a move under a module's own `record` rolls out when it recreates none of its containers
// and moves none of its data, judged from the two builds' manifests.
func TestWhatAMoveUnderRecordHoldsFor(t *testing.T) {
	base := func() Manifest {
		raw := `{"module":"mailu","tools":["mailu_status"],
		  "requires":["postgres-database"],
		  "data":{"own":[{"id":"mail","path":"${dir:data-mail}","class":"valuable"}]},
		  "bundles":[{"name":"tools","source":"store/mailu-tools@sha256:aaa","digest":"sha256:aaa"}],
		  "resources":[
		    {"id":"state","type":"directory"},
		    {"id":"mesh-state","type":"directory"},
		    {"id":"data-mail","type":"directory"},
		    {"id":"config-env","type":"file","path":"${dir:state}/mailu.env","content":"A=1"},
		    {"id":"runtime-config","type":"file","path":"${dir:mesh-state}/config.json","content":"{}"},
		    {"id":"inbox-note","type":"file","path":"${dir:data-mail}/README","content":"x"},
		    {"id":"imap","type":"container","image":"registry/imap@sha256:1","volumes":["${dir:data-mail}:/mail"],
		     "env-file":["${dir:state}/mailu.env"]},
		    {"id":"watcher","type":"process","command":"watch"},
		    {"id":"installation","type":"archive","path":"/opt/mailu-tools","artifact":"archive"},
		    {"id":"guard","type":"package","package":"nftables"}]}`
		var m Manifest
		if err := json.Unmarshal([]byte(raw), &m); err != nil {
			t.Fatal(err)
		}
		return m
	}
	resource := func(m *Manifest, id string) map[string]any {
		for _, r := range m.Resources {
			if r["id"] == id {
				return r
			}
		}
		t.Fatalf("no resource %s", id)
		return nil
	}
	cases := []struct {
		name   string
		change func(m *Manifest)
		holds  string // empty: it rolls out
	}{
		{"nothing", func(*Manifest) {}, ""},
		{"a tools bundle", func(m *Manifest) {
			m.Bundles[0].Digest, m.Bundles[0].Source = "sha256:bbb", "store/mailu-tools@sha256:bbb"
		}, ""},
		{"the tool list", func(m *Manifest) { m.Tools = append(m.Tools, "mailu_queue") }, ""},
		{"a file no container mounts", func(m *Manifest) { resource(m, "runtime-config")["content"] = `{"a":1}` }, ""},
		{"a container's image", func(m *Manifest) { resource(m, "imap")["image"] = "registry/imap@sha256:2" }, "recreates 1 of mailu's 1"},
		{"a container's declaration", func(m *Manifest) { resource(m, "imap")["health"] = map[string]any{"kind": "runtime"} }, "recreates 1"},
		{"a container added", func(m *Manifest) {
			m.Resources = append(m.Resources, map[string]any{"id": "smtp", "type": "container", "image": "x"})
		}, "recreates"},
		{"a mounted file", func(m *Manifest) { resource(m, "config-env")["content"] = "A=2" }, "which its container imap mounts"},
		{"a file within declared data", func(m *Manifest) { resource(m, "inbox-note")["content"] = "y" }, "which its container imap mounts"},
		{"a directory holding declared data", func(m *Manifest) { resource(m, "data-mail")["mode"] = "0700" }, "data-mail"},
		{"the data declaration", func(m *Manifest) { m.Data.Own[0].Class = ClassIrreplaceable }, "data declaration"},
		{"a provider", func(m *Manifest) { m.Requires = append(m.Requires, "s3") }, "what it requires"},
		{"what it provides", func(m *Manifest) { m.Provides = append(m.Provides, Offer{Name: "smtp"}) }, "what it provides"},
		{"a process of a module with data", func(m *Manifest) { resource(m, "watcher")["command"] = "watch2" }, "long-running process watcher"},
		{"an archive resource", func(m *Manifest) { resource(m, "installation")["artifact"] = "archive2" }, "the archive installation"},
		{"a package resource", func(m *Manifest) { resource(m, "guard")["package"] = "nftables2" }, "the package guard"},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			from, to := base(), base()
			c.change(&to)
			got := Holds(from, to)
			switch {
			case c.holds == "" && got != "":
				t.Fatalf("held: %s", got)
			case c.holds != "" && !strings.Contains(got, c.holds):
				t.Fatalf("holds %q; want it to say %q", got, c.holds)
			}
		})
	}
	// A data directory nothing mounts still holds its data.
	from, to := base(), base()
	from.Data.Own = append(from.Data.Own, DataItem{ID: "archive", Path: "${dir:mesh-state}/archive", Class: "valuable"})
	to.Data = &Data{Own: append([]DataItem(nil), from.Data.Own...)}
	resource(&to, "runtime-config")["path"] = "${dir:mesh-state}/archive/config.json"
	resource(&from, "runtime-config")["path"] = "${dir:mesh-state}/archive/config.json"
	resource(&to, "runtime-config")["content"] = "new"
	if got := Holds(from, to); !strings.Contains(got, "lies within its data archive") {
		t.Fatalf("a file within data nothing mounts: %q", got)
	}
	// A process of a module with no data of its own may change.
	from, to = base(), base()
	from.Data, to.Data = nil, nil
	resource(&to, "watcher")["command"] = "watch2"
	if got := Holds(from, to); got != "" {
		t.Fatalf("a process of a module with no data held: %s", got)
	}
}