Documentation
¶
Overview ¶
Package radio plays internet radio: Icecast and Shoutcast streams, pls and m3u playlists of them, and audio HLS. A background goroutine owns the network and the decoder and fills a bounded buffer of PCM, so the audio player reading a Stream never waits on the network.
Index ¶
- Variables
- func NewHTTPClient() *http.Client
- type Kind
- type Options
- type Probe
- type Stream
- func (s *Stream) Buffered() int
- func (s *Stream) Close() error
- func (s *Stream) Err() error
- func (*Stream) Len() int
- func (*Stream) Live() bool
- func (s *Stream) Name() string
- func (s *Stream) Position() int
- func (s *Stream) Resume()
- func (s *Stream) SampleRate() int
- func (*Stream) Seek(int) error
- func (s *Stream) Stream(samples [][2]float64) (int, bool)
- func (s *Stream) Suspend()
Constants ¶
This section is empty.
Variables ¶
var ( // ErrLive is returned by Stream.Seek: a live stream has no positions. ErrLive = errors.New("radio: live streams cannot seek") // ErrUnsupported is a stream in a codec or format this package does not // play, such as Opus. ErrUnsupported = errors.New("radio: unsupported stream format") // ErrTooLarge is a response bigger than its limit. ErrTooLarge = errors.New("radio: response too large") // ErrClosed is returned once a Stream is closed. ErrClosed = errors.New("radio: stream closed") )
Functions ¶
func NewHTTPClient ¶
NewHTTPClient returns the client radio uses: the Zaparoo User-Agent, the configured TLS roots, bounded dial, TLS and header waits, at most ten redirects, and plain http allowed, as many radio stations still serve it. It reads Shoutcast v1 servers, which answer "ICY 200 OK" instead of an HTTP status line. There is no overall timeout: a stream is endless. It is meant for audio only.
Types ¶
type Kind ¶
type Kind int
Kind is what a probed URL serves.
const ( // KindNotAudio is anything this package cannot play, such as a web page. KindNotAudio Kind = iota // KindStream is a direct Icecast or Shoutcast stream of MP3, AAC or Ogg // Vorbis. KindStream // KindHLS is an HTTP Live Streaming playlist. KindHLS // KindPlaylist is a pls or m3u playlist of stream URLs. KindPlaylist )
type Options ¶
type Options struct {
// OnMeta is called with the new title whenever the stream announces
// one (ICY StreamTitle, HLS ID3 tags). It runs on the network
// goroutine, so it must not block or call Close.
OnMeta func(title, artist string)
// HTTPClient makes every request; nil uses NewHTTPClient.
HTTPClient *http.Client
// ResourceConstrained picks the lowest bandwidth HLS variant.
ResourceConstrained bool
// contains filtered or unexported fields
}
Options configures Open.
type Probe ¶
type Probe struct {
// contains filtered or unexported fields
}
Probe is a URL opened and classified by ProbeURL. A stream probe holds its response open so Open can play from it without connecting again.
func ProbeURL ¶
ProbeURL requests rawURL, with ICY metadata asked for, and classifies the response by Content-Type, sniffing its first bytes when the type is generic. ctx bounds only the request, headers and sniffing: the stream response the probe keeps is not tied to it, so the caller may cancel ctx once ProbeURL returns. A KindNotAudio probe is still open; Close it.
func (*Probe) Close ¶
func (p *Probe) Close()
Close releases the probe's connection. It is idempotent and safe on nil.
type Stream ¶
type Stream struct {
// contains filtered or unexported fields
}
Stream is a playing radio stream: a beep.StreamSeekCloser whose audio a background goroutine reads from the network, decodes and buffers. Stream never blocks on the network.
func Open ¶
Open starts playing a probed stream and takes ownership of p. It resolves a playlist to the first entry that plays, and returns once audio is decoded, so the sample rate is known; ctx bounds only that wait. It reuses the probe's connection when it is still usable.
func (*Stream) Buffered ¶
Buffered is how many frames Stream can return now. Once no more audio will arrive it is larger, so a reader pulling at most Buffered frames also reaches the end.
func (*Stream) Close ¶
Close stops the stream and waits for its goroutine. It is safe to call more than once and while the network is blocked.
func (*Stream) Err ¶
Err is why the stream stopped, or nil while it plays, after a clean end and after Close.
func (*Stream) Resume ¶
func (s *Stream) Resume()
Resume reconnects a suspended stream at the live point.
func (*Stream) SampleRate ¶
SampleRate is the rate of the frames Stream returns, fixed for the life of the stream.
Source Files