feat: refresh assets when listing root level dirs

ghafs.go

@@ -14,13 +14,13 @@ import (
 
 // ghaFS implements the GitHub Release Assets file system.
 type ghaFS struct {
-	rasm  *ReleaseAssetsMap
+	mgmt  *ReleaseAssetsMgmt
 	token *string
 }
 
 // root implements both Node and Handle for the root directory.
 type root struct {
-	rasm  *ReleaseAssetsMap
+	mgmt  *ReleaseAssetsMgmt
 	token *string
 }
 
@@ -30,12 +30,12 @@ type tagDir struct {
 	token *string
 }
 
-func NewGhaFS(rasm *ReleaseAssetsMap, token *string) ghaFS {
-	return ghaFS{rasm, token}
+func NewGhaFS(mgmt *ReleaseAssetsMgmt, token *string) ghaFS {
+	return ghaFS{mgmt, token}
 }
 
 func (g ghaFS) Root() (fs.Node, error) {
-	return root{rasm: g.rasm, token: g.token}, nil
+	return root{mgmt: g.mgmt, token: g.token}, nil
 }
 
 func (root) Attr(ctx context.Context, a *fuse.Attr) error {
@@ -45,11 +45,17 @@ func (root) Attr(ctx context.Context, a *fuse.Attr) error {
 }
 
 func (r root) ReadDirAll(ctx context.Context) ([]fuse.Dirent, error) {
-	return rasToDirents(r.rasm), nil
+	rasm, err := r.mgmt.refresh()
+
+	if err != nil {
+		return nil, err
+	}
+
+	return rasToDirents(rasm), nil
 }
 
 func (r root) Lookup(ctx context.Context, name string) (fs.Node, error) {
-	for tag, ras := range *r.rasm {
+	for tag, ras := range *r.mgmt.getCurrent() {
 		if name == tag {
 			return tagDir{ras: &ras, token: r.token}, nil
 		}

main.go

@@ -45,7 +45,7 @@ func main() {
 	}
 
 	client := github.NewClient(tc)
-	rasm, err := getReleaseAssets(ctx, client, owner, repo)
+	mgmt, err := makeReleaseAssetsMgmt(ctx, client, owner, repo)
 
 	if err != nil {
 		log.Fatal(err)
@@ -72,7 +72,7 @@ func main() {
 		token = &oauth2Token
 	}
 
-	err = fs.Serve(c, NewGhaFS(rasm, token))
+	err = fs.Serve(c, NewGhaFS(mgmt, token))
 	if err != nil {
 		log.Fatal(err)
 	}

releaseAssets.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"context"
+	"sync"
 
 	"github.com/google/go-github/v28/github"
 )
@@ -37,3 +38,44 @@ func getReleaseAssets(ctx context.Context, client *github.Client, owner string,
 
 	return &rasm, nil
 }
+
+type ReleaseAssetsMgmt struct {
+	ctx    context.Context
+	client *github.Client
+	owner  string
+	repo   string
+
+	current *ReleaseAssetsMap
+	m       sync.Mutex
+}
+
+func makeReleaseAssetsMgmt(ctx context.Context, client *github.Client, owner string, repo string) (*ReleaseAssetsMgmt, error) {
+	var mgmt ReleaseAssetsMgmt
+	mgmt.ctx = ctx
+	mgmt.client = client
+	mgmt.owner = owner
+	mgmt.repo = repo
+
+	_, err := mgmt.refresh()
+	return &mgmt, err
+}
+
+func (mgmt *ReleaseAssetsMgmt) refresh() (*ReleaseAssetsMap, error) {
+	mgmt.m.Lock()
+	defer mgmt.m.Unlock()
+
+	var err error
+	mgmt.current, err = getReleaseAssets(mgmt.ctx, mgmt.client, mgmt.owner, mgmt.repo)
+
+	// See getCurrent for comments about correctness
+	return mgmt.current, err
+}
+
+func (mgmt *ReleaseAssetsMgmt) getCurrent() *ReleaseAssetsMap {
+	// For simplicity, we assume readonly access to ReleaseAssetsMgmt
+	// so that we do not need to lock and return a cloned ReleaseAssetsMap
+	// for correctness
+	mgmt.m.Lock()
+	defer mgmt.m.Unlock()
+	return mgmt.current
+}