10 feat download queue (#59)

* testing message queue

* better mq syncronisation

* major code refactoring, concern separation.

* bugfix

* code refactoring

* queuesize configurable via flags

* code refactoring

* comments

* code refactoring, updated readme

server/rpc/service.go

@@ -0,0 +1,159 @@
+package rpc
+
+import (
+	"log"
+
+	"github.com/marcopeocchi/yt-dlp-web-ui/server/internal"
+	"github.com/marcopeocchi/yt-dlp-web-ui/server/sys"
+	"github.com/marcopeocchi/yt-dlp-web-ui/server/updater"
+)
+
+type Service struct {
+	db *internal.MemoryDB
+	mq *internal.MessageQueue
+}
+
+type Running []internal.ProcessResponse
+type Pending []string
+
+type NoArgs struct{}
+
+type Args struct {
+	Id     string
+	URL    string
+	Params []string
+}
+
+type DownloadSpecificArgs struct {
+	Id     string
+	URL    string
+	Path   string
+	Rename string
+	Params []string
+}
+
+// Dependency injection container.
+func Container(db *internal.MemoryDB, mq *internal.MessageQueue) *Service {
+	return &Service{
+		db: db,
+		mq: mq,
+	}
+}
+
+// Exec spawns a Process.
+// The result of the execution is the newly spawned process Id.
+func (s *Service) Exec(args DownloadSpecificArgs, result *string) error {
+	log.Println("Sending new process to message queue", args.URL)
+
+	p := &internal.Process{
+		DB:     s.db,
+		Url:    args.URL,
+		Params: args.Params,
+		Output: internal.DownloadOutput{
+			Path:     args.Path,
+			Filename: args.Rename,
+		},
+	}
+
+	s.mq.Publish(p)
+	*result = p.Id
+
+	return nil
+}
+
+// Progess retrieves the Progress of a specific Process given its Id
+func (s *Service) Progess(args Args, progress *internal.DownloadProgress) error {
+	proc, err := s.db.Get(args.Id)
+	if err != nil {
+		return err
+	}
+	*progress = proc.Progress
+	return nil
+}
+
+// Progess retrieves the Progress of a specific Process given its Id
+func (s *Service) Formats(args Args, progress *internal.DownloadFormats) error {
+	var err error
+	p := internal.Process{Url: args.URL}
+	*progress, err = p.GetFormatsSync()
+	return err
+}
+
+// Pending retrieves a slice of all Pending/Running processes ids
+func (s *Service) Pending(args NoArgs, pending *Pending) error {
+	*pending = *s.db.Keys()
+	return nil
+}
+
+// Running retrieves a slice of all Processes progress
+func (s *Service) Running(args NoArgs, running *Running) error {
+	*running = *s.db.All()
+	return nil
+}
+
+// Kill kills a process given its id and remove it from the memoryDB
+func (s *Service) Kill(args string, killed *string) error {
+	log.Println("Trying killing process with id", args)
+	proc, err := s.db.Get(args)
+
+	if err != nil {
+		return err
+	}
+	if proc != nil {
+		err = proc.Kill()
+	}
+
+	s.db.Delete(proc.Id)
+	return err
+}
+
+// KillAll kills all process unconditionally and removes them from
+// the memory db
+func (s *Service) KillAll(args NoArgs, killed *string) error {
+	log.Println("Killing all spawned processes", args)
+	keys := s.db.Keys()
+	var err error
+	for _, key := range *keys {
+		proc, err := s.db.Get(key)
+		if err != nil {
+			return err
+		}
+		if proc != nil {
+			proc.Kill()
+		}
+	}
+	return err
+}
+
+// Remove a process from the db rendering it unusable if active
+func (s *Service) Clear(args string, killed *string) error {
+	log.Println("Clearing process with id", args)
+	s.db.Delete(args)
+	return nil
+}
+
+// FreeSpace gets the available from package sys util
+func (s *Service) FreeSpace(args NoArgs, free *uint64) error {
+	freeSpace, err := sys.FreeSpace()
+	*free = freeSpace
+	return err
+}
+
+// Return a flattned tree of the download directory
+func (s *Service) DirectoryTree(args NoArgs, tree *[]string) error {
+	dfsTree, err := sys.DirectoryTree()
+	*tree = *dfsTree
+	return err
+}
+
+// Updates the yt-dlp binary using its builtin function
+func (s *Service) UpdateExecutable(args NoArgs, updated *bool) error {
+	log.Println("Updating yt-dlp executable to the latest release")
+	err := updater.UpdateExecutable()
+	if err != nil {
+		*updated = true
+		return err
+	}
+	*updated = false
+	return err
+}