implement spotify source extension

.gitignore

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+.idea/

README.md

@@ -1 +1,62 @@
-# spotify-plugin
+[![Go Reference](https://pkg.go.dev/badge/github.com/DisgoOrg/spotify-plugin.svg)](https://pkg.go.dev/github.com/DisgoOrg/spotify-plugin)
+[![Go Report](https://goreportcard.com/badge/github.com/DisgoOrg/spotify-plugin)](https://goreportcard.com/report/github.com/DisgoOrg/spotify-plugin)
+[![Go Version](https://img.shields.io/github/go-mod/go-version/DisgoOrg/spotify-plugin)](https://golang.org/doc/devel/release.html)
+[![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://github.com/DisgoOrg/spotify-plugin/blob/master/LICENSE)
+[![Disgo Version](https://img.shields.io/github/v/tag/DisgoOrg/spotify-plugin?label=release)](https://github.com/DisgoOrg/spotify-plugin/releases/latest)
+[![Disgo Discord](https://discord.com/api/guilds/817327181659111454/widget.png)](https://discord.gg/NFmvZYmZMF)
+
+# spotify-plugin
+
+spotify-plugin is a [Lavalink](https://github.com/freyacodes/Lavalink) Client which supports the latest Lavalink 3.4 release
+
+## Getting Started
+
+### Installing
+
+```sh
+go get github.com/DisgoOrg/spotify-plugin
+```
+
+## Usage
+
+```go
+import (
+    "github.com/DisgoOrg/disgolink/lavalink"
+    "github.com/DisgoOrg/spotify-plugin"
+)
+// create new lavalink and add the spotify plugin
+link := lavalink.New(
+    lavalink.WithUserID("user_id_here"),
+    lavalink.WithPlugins(spotify.New()),
+)
+
+// when loading track you can type cast the track to a spotify track to access extra data
+_ = link.BestRestClient().LoadItemHandler("https://open.spotify.com/track/3yk51U329nwdpeIHV0O5ez", lavalink.NewResultHandler(
+    func (track lavalink.AudioTrack) {
+        if spotifyTrack, ok := track.(*spotify.AudioTrack); ok {
+            println("ISRC: ", spotifyTrack.AudioTrackInfo.ISRC)
+            println("ArtworkURL: ", spotifyTrack.AudioTrackInfo.ArtworkURL)
+        }
+    },
+    func (playlist lavalink.AudioPlaylist) {},
+    func (tracks []lavalink.AudioTrack) {},
+    func () {},
+    func (ex lavalink.FriendlyException) {},
+))
+```
+
+## Example
+
+You can find an example under [_example](https://github.com/DisgoOrg/spotify-plugin/tree/master/_example)
+
+## Troubleshooting
+
+For help feel free to open an issues or reach out on [Discord](https://discord.gg/NFmvZYmZMF)
+
+## Contributing
+
+Contributions are welcomed but for bigger changes please first reach out via [Discord](https://discord.gg/NFmvZYmZMF) or create an issue to discuss your intentions and ideas.
+
+## License
+
+Distributed under the [![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://github.com/DisgoOrg/spotify-plugin/blob/master/LICENSE). See LICENSE for more information.

go.mod

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+module github.com/DisgoOrg/spotify-plugin
+
+go 1.17
+
+require (
+	github.com/DisgoOrg/disgolink v1.1.1
+)
+
+require (
+	github.com/DisgoOrg/log v1.1.2 // indirect
+	github.com/DisgoOrg/snowflake v1.0.1 // indirect
+	github.com/gorilla/websocket v1.4.2 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+)

go.sum

@@ -0,0 +1,20 @@
+github.com/DisgoOrg/disgolink v1.1.1 h1:AYs4gZa920ejBaj8QZZD15rZTidUzCVaEe7zGAOy+4w=
+github.com/DisgoOrg/disgolink v1.1.1/go.mod h1:6iqOB9yi9MbNB804oVlhFO9Ba5A31Tb/4q95wKhm0bc=
+github.com/DisgoOrg/log v1.1.2 h1:tGJS4jaH1PyjPRHybHp8WpYJ/4fR3fYWT4Mv1PoDGBM=
+github.com/DisgoOrg/log v1.1.2/go.mod h1:tSMofXaNhQNvzLRoL4tAiCG9yGY1ES5DLvduh7e9GRU=
+github.com/DisgoOrg/snowflake v1.0.1 h1:+UKgfjOnj2KBj/20tWKFNzhbo9awzThkY12ZaOQzaSg=
+github.com/DisgoOrg/snowflake v1.0.1/go.mod h1:jIQVlVmElm2OGt6v52ITf/71ODaU09chUCflxt8+3yM=
+github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/gorilla/websocket v1.4.2 h1:+/TMaTYc4QFitKJxsQ7Yye35DkWvkdLcvGKqM+x0Ufc=
+github.com/gorilla/websocket v1.4.2/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
+github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.7.0 h1:nwc3DEeHmmLAfoZucVR881uASk0Mfjw8xYJ99tb5CcY=
+github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c h1:dUUwHk2QECo/6vqA44rthZ8ie2QXMNeKRTHCNY2nXvo=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

spotify_plugin.go

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+package spotify
+
+import (
+	"errors"
+	"io"
+
+	"github.com/DisgoOrg/disgolink/lavalink"
+)
+
+const SearchTypeSpotify lavalink.SearchType = "spsearch"
+
+var (
+	_ lavalink.SourceExtension = (*Plugin)(nil)
+)
+
+func New() *Plugin {
+	return &Plugin{}
+}
+
+type Plugin struct{}
+
+func (p *Plugin) SourceName() string {
+	return "spotify"
+}
+
+func (p *Plugin) Encode(track lavalink.AudioTrack, w io.Writer) (err error) {
+	spotifyTrack, ok := track.(*AudioTrack)
+	if !ok {
+		return errors.New("track is not a SpotifyAudioTrack")
+	}
+
+	if err = lavalink.WriteNullableString(w, spotifyTrack.AudioTrackInfo.ISRC); err != nil {
+		return
+	}
+	return lavalink.WriteNullableString(w, spotifyTrack.AudioTrackInfo.ArtworkURL)
+}
+
+func (p *Plugin) Decode(track string, info lavalink.AudioTrackInfo, r io.Reader) (spotifyTrack lavalink.AudioTrack, err error) {
+	var isrc, artworkURL *string
+
+	if isrc, err = lavalink.ReadNullableString(r); err != nil {
+		return
+	}
+	if artworkURL, err = lavalink.ReadNullableString(r); err != nil {
+		return
+	}
+
+	return &AudioTrack{
+		AudioTrack: track,
+		AudioTrackInfo: &AudioTrackInfo{
+			AudioTrackInfo: info,
+			ISRC:           isrc,
+			ArtworkURL:     artworkURL,
+		},
+	}, nil
+}
+
+var (
+	_ lavalink.AudioTrack     = (*AudioTrack)(nil)
+	_ lavalink.AudioTrackInfo = (*AudioTrackInfo)(nil)
+)
+
+type AudioTrack struct {
+	AudioTrack     string          `json:"track"`
+	AudioTrackInfo *AudioTrackInfo `json:"info"`
+}
+
+func (t *AudioTrack) Track() string {
+	return t.AudioTrack
+}
+
+func (t *AudioTrack) Info() lavalink.AudioTrackInfo {
+	return t.AudioTrackInfo
+}
+
+type AudioTrackInfo struct {
+	lavalink.AudioTrackInfo
+	ISRC       *string `json:"isrc"`
+	ArtworkURL *string `json:"artwork_url"`
+}