app/instance: wrap internal implementation

This reduces the scope of the fst package, which was growing questionably large.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/state/multi.go

@@ -14,6 +14,7 @@ import (
 	"syscall"
 
 	"git.gensokyo.uk/security/fortify/fst"
+	"git.gensokyo.uk/security/fortify/internal/app"
 	"git.gensokyo.uk/security/fortify/internal/fmsg"
 )
 
@@ -129,7 +130,7 @@ type multiBackend struct {
 	lock sync.RWMutex
 }
 
-func (b *multiBackend) filename(id *fst.ID) string {
+func (b *multiBackend) filename(id *app.ID) string {
 	return path.Join(b.path, id.String())
 }
 
@@ -189,8 +190,8 @@ func (b *multiBackend) load(decode bool) (Entries, error) {
 			return nil, fmt.Errorf("unexpected directory %q in store", e.Name())
 		}
 
-		id := new(fst.ID)
-		if err := fst.ParseAppID(id, e.Name()); err != nil {
+		id := new(app.ID)
+		if err := app.ParseAppID(id, e.Name()); err != nil {
 			return nil, err
 		}
 
@@ -335,7 +336,7 @@ func (b *multiBackend) encodeState(w io.WriteSeeker, state *State, configWriter
 	return err
 }
 
-func (b *multiBackend) Destroy(id fst.ID) error {
+func (b *multiBackend) Destroy(id app.ID) error {
 	b.lock.Lock()
 	defer b.lock.Unlock()
 

internal/state/state.go

@@ -6,11 +6,12 @@ import (
 	"time"
 
 	"git.gensokyo.uk/security/fortify/fst"
+	"git.gensokyo.uk/security/fortify/internal/app"
 )
 
 var ErrNoConfig = errors.New("state does not contain config")
 
-type Entries map[fst.ID]*State
+type Entries map[app.ID]*State
 
 type Store interface {
 	// Do calls f exactly once and ensures store exclusivity until f returns.
@@ -29,7 +30,7 @@ type Store interface {
 // Cursor provides access to the store
 type Cursor interface {
 	Save(state *State, configWriter io.WriterTo) error
-	Destroy(id fst.ID) error
+	Destroy(id app.ID) error
 	Load() (Entries, error)
 	Len() (int, error)
 }
@@ -37,7 +38,7 @@ type Cursor interface {
 // State is a fortify process's state
 type State struct {
 	// fortify instance id
-	ID fst.ID `json:"instance"`
+	ID app.ID `json:"instance"`
 	// child process PID value
 	PID int `json:"pid"`
 	// sealed app configuration

internal/state/state_test.go

@@ -11,6 +11,7 @@ import (
 	"time"
 
 	"git.gensokyo.uk/security/fortify/fst"
+	"git.gensokyo.uk/security/fortify/internal/app"
 	"git.gensokyo.uk/security/fortify/internal/state"
 )
 
@@ -133,7 +134,7 @@ func testStore(t *testing.T, s state.Store) {
 }
 
 func makeState(t *testing.T, s *state.State, ct io.Writer) {
-	if err := fst.NewAppID(&s.ID); err != nil {
+	if err := app.NewAppID(&s.ID); err != nil {
 		t.Fatalf("cannot create dummy state: %v", err)
 	}
 	if err := gob.NewEncoder(ct).Encode(fst.Template()); err != nil {