fix: hanging goroutine in get fileArchive handler

Fixes #8957

The context was only checked while reading data.
Not while writing data to the http connection.
So since the data flow through an io.Pipe the closing didn't flowed through and left the writer open hanging.

Co-authored-by: Antonio Navarro Perez <antnavper@gmail.com>

core/commands/get.go

@@ -61,6 +61,7 @@ may also specify the level of compression by specifying '-l=<1-9>'.
 		return err
 	},
 	Run: func(req *cmds.Request, res cmds.ResponseEmitter, env cmds.Environment) error {
+		ctx := req.Context
 		cmplvl, err := getCompressOptions(req)
 		if err != nil {
 			return err
@@ -73,7 +74,7 @@ may also specify the level of compression by specifying '-l=<1-9>'.
 
 		p := path.New(req.Arguments[0])
 
-		file, err := api.Unixfs().Get(req.Context, p)
+		file, err := api.Unixfs().Get(ctx, p)
 		if err != nil {
 			return err
 		}
@@ -90,6 +91,13 @@ may also specify the level of compression by specifying '-l=<1-9>'.
 		if err != nil {
 			return err
 		}
+		go func() {
+			// We cannot defer a close in the response writer (like we should)
+			// Because the cmd framework outsmart us and doesn't call response
+			// if the context is over.
+			<-ctx.Done()
+			reader.Close()
+		}()
 
 		return res.Emit(reader)
 	},
@@ -273,7 +281,7 @@ func (i *identityWriteCloser) Close() error {
 	return nil
 }
 
-func fileArchive(f files.Node, name string, archive bool, compression int) (io.Reader, error) {
+func fileArchive(f files.Node, name string, archive bool, compression int) (io.ReadCloser, error) {
 	cleaned := gopath.Clean(name)
 	_, filename := gopath.Split(cleaned)