| 1 | package activator |
| 2 | |
| 3 | import ( |
| 4 | "encoding/json" |
| 5 | "errors" |
| 6 | "fmt" |
| 7 | "os" |
| 8 | "path/filepath" |
| 9 | |
| 10 | "github.com/carlosframework/platform/internal/provision" |
| 11 | ) |
| 12 | |
| 13 | // InstallMarker is a box's own note that it finished a local install of |
| 14 | // one generation of a host. Nothing reads it to trust a local database: |
| 15 | // claim ruling R6 has every admitted writer purge and restore from the |
| 16 | // certified remote (region HA spec 1 H13, §5.5 withdrawn). It is kept for |
| 17 | // relocation's local install journal (§5.8), which plan 1b does not build. |
| 18 | type InstallMarker struct { |
| 19 | Incarnation string `json:"incarnation"` |
| 20 | Generation string `json:"generation"` |
| 21 | Stamp int64 `json:"stamp"` |
| 22 | DBMarker string `json:"db_marker"` |
| 23 | FilesSeq int64 `json:"files_seq"` |
| 24 | } |
| 25 | |
| 26 | func InstallMarkerPath(dataDir, host string) string { |
| 27 | return filepath.Join(dataDir, ".installed", provision.InstanceID(host)+".json") |
| 28 | } |
| 29 | |
| 30 | // WriteInstallMarker replaces the marker atomically and syncs both the |
| 31 | // file and its directory, so a marker that is read back was fully written. |
| 32 | func WriteInstallMarker(dataDir, host string, m InstallMarker) error { |
| 33 | path := InstallMarkerPath(dataDir, host) |
| 34 | dir := filepath.Dir(path) |
| 35 | if err := os.MkdirAll(dir, 0o700); err != nil { |
| 36 | return err |
| 37 | } |
| 38 | body, err := json.Marshal(m) |
| 39 | if err != nil { |
| 40 | return err |
| 41 | } |
| 42 | tmp, err := os.CreateTemp(dir, ".marker-*") |
| 43 | if err != nil { |
| 44 | return err |
| 45 | } |
| 46 | defer os.Remove(tmp.Name()) |
| 47 | if _, err := tmp.Write(body); err != nil { |
| 48 | tmp.Close() |
| 49 | return err |
| 50 | } |
| 51 | if err := tmp.Sync(); err != nil { |
| 52 | tmp.Close() |
| 53 | return err |
| 54 | } |
| 55 | if err := tmp.Close(); err != nil { |
| 56 | return err |
| 57 | } |
| 58 | if err := os.Rename(tmp.Name(), path); err != nil { |
| 59 | return err |
| 60 | } |
| 61 | d, err := os.Open(dir) |
| 62 | if err != nil { |
| 63 | return err |
| 64 | } |
| 65 | defer d.Close() |
| 66 | return d.Sync() |
| 67 | } |
| 68 | |
| 69 | // ReadInstallMarker returns the marker and whether there is one. A marker |
| 70 | // that exists but cannot be parsed is an error, never "absent": the caller |
| 71 | // restores either way, but it must not mistake damage for a clean slate. |
| 72 | func ReadInstallMarker(dataDir, host string) (InstallMarker, bool, error) { |
| 73 | body, err := os.ReadFile(InstallMarkerPath(dataDir, host)) |
| 74 | if errors.Is(err, os.ErrNotExist) { |
| 75 | return InstallMarker{}, false, nil |
| 76 | } |
| 77 | if err != nil { |
| 78 | return InstallMarker{}, false, err |
| 79 | } |
| 80 | var m InstallMarker |
| 81 | if err := json.Unmarshal(body, &m); err != nil { |
| 82 | return InstallMarker{}, false, fmt.Errorf("activator: install marker for %s: %w", host, err) |
| 83 | } |
| 84 | return m, true, nil |
| 85 | } |
| 86 | |
| 87 | func RemoveInstallMarker(dataDir, host string) error { |
| 88 | err := os.Remove(InstallMarkerPath(dataDir, host)) |
| 89 | if errors.Is(err, os.ErrNotExist) { |
| 90 | return nil |
| 91 | } |
| 92 | return err |
| 93 | } |
| 94 | |
amadan