//Src returns a channel of gonzo.Files that match the provided patterns.
//TODO: ADD support for prefix to avoid all the util.Trims
func Src(ctx context.Context, globs ...string) gonzo.Pipe {
ctx, cancel := context.WithCancel(ctx)
files := make(chan gonzo.File)
pipe := gonzo.NewPipe(ctx, files)
//TODO: Parse globs here, check for invalid globs, split them into "filters".
go func() {
var err error
defer close(files)
fileslist, err := glob.Glob(globs...)
if err != nil {
ctx.Error(err)
return
}
for mp := range fileslist {
var (
file gonzo.File
base = glob.Dir(mp.Glob)
name = mp.Name
)
file, err = Read(mp.Name)
ctx = context.WithValue(ctx, "file", name)
if err == ErrIsDir {
ctx.Warn("fs.Src Ignored Directory.")
continue
}
if err != nil {
cancel()
ctx.Error(err)
return
}
file.FileInfo().SetBase(base)
file.FileInfo().SetName(name)
files <- file
}
}()
return pipe
}
// Merges the output of multiple chan of gonzo.File into a pipe in a serial manner.
// (i.e Reads first chan until the end and moves to the next until the last channel is finished.
func Queue(pipe gonzo.Pipe, pipes ...gonzo.Pipe) gonzo.Pipe {
if len(pipes) == 0 {
return pipe
}
pipes = append([]gonzo.Pipe{pipe}, pipes...)
ctx, cancel := context.WithCancel(pipe.Context())
for _, pipe := range pipes {
go func(c context.Context) {
<-c.Done()
cancel()
}(pipe.Context())
}
out := make(chan gonzo.File)
go func(out chan gonzo.File) {
defer close(out)
for _, p := range pipes {
func(files <-chan gonzo.File) {
for {
select {
case f, ok := <-files:
if !ok {
return
}
out <- f
case <-ctx.Done():
return
}
}
}(p.Files())
if ctx.Err() != nil {
return
}
}
}(out)
return gonzo.NewPipe(ctx, out)
}
// Merge concurrently Merges the output of multiple chan of gonzo.File into a pipe.
func Merge(ctx context.Context, pipes ...gonzo.Pipe) gonzo.Pipe {
ctx, cancel := context.WithCancel(ctx)
for _, pipe := range pipes {
go func(c context.Context) {
<-c.Done()
cancel()
}(pipe.Context())
}
out := make(chan gonzo.File)
go func(out chan gonzo.File) {
var wg sync.WaitGroup
wg.Add(len(pipes))
defer close(out)
for _, p := range pipes {
go func(p gonzo.Pipe) {
defer wg.Done()
files := p.Files()
ctx := p.Context()
for {
select {
case f, ok := <-files:
if !ok {
return
}
out <- f
case <-ctx.Done():
return
}
}
}(p)
}
wg.Wait()
}(out)
return gonzo.NewPipe(ctx, out)
}
// Gets the list of urls and passes the results to output channel.
// It reports the progress to the Context using a ReadProgress proxy.
func Get(ctx context.Context, urls ...string) gonzo.Pipe {
ctx, cancel := context.WithCancel(ctx)
out := make(chan gonzo.File)
client := &http.Client{}
go func() {
defer close(out)
for _, url := range urls {
if url == "" {
ctx.Error("Empty URL.")
cancel()
return
}
select {
case <-ctx.Done():
ctx.Warn(context.Canceled)
return
default:
ctx.Infof("Downloading %s", url)
file, err := get(ctx, client, url)
if err != nil {
ctx.Error(err)
cancel()
break
}
//TODO: Add progress meter.
//s, _ := file.Stat()
//file.Reader = c.ReadProgress(file.Reader, "Downloading "+file.Path, s.Size())
out <- file
}
}
}()
return gonzo.NewPipe(ctx, out)
}
