go-mastodon/streaming.go

135 lines
2.9 KiB
Go

package mastodon
import (
"bufio"
"context"
"encoding/json"
"fmt"
"io"
"net/http"
"net/url"
"path"
"strings"
"time"
)
// UpdateEvent is struct for passing status event to app.
type UpdateEvent struct{ Status *Status }
func (e *UpdateEvent) event() {}
// NotificationEvent is struct for passing notification event to app.
type NotificationEvent struct{}
func (e *NotificationEvent) event() {}
// DeleteEvent is struct for passing deletion event to app.
type DeleteEvent struct{ ID int64 }
func (e *DeleteEvent) event() {}
// ErrorEvent is struct for passing errors to app.
type ErrorEvent struct{ err error }
func (e *ErrorEvent) event() {}
func (e *ErrorEvent) Error() string { return e.err.Error() }
// Event is interface passing events to app.
type Event interface {
event()
}
func handleReader(ctx context.Context, q chan Event, r io.Reader) error {
name := ""
s := bufio.NewScanner(r)
for s.Scan() {
line := s.Text()
token := strings.SplitN(line, ":", 2)
if len(token) != 2 {
continue
}
switch strings.TrimSpace(token[0]) {
case "event":
name = strings.TrimSpace(token[1])
case "data":
switch name {
case "update":
var status Status
err := json.Unmarshal([]byte(token[1]), &status)
if err == nil {
q <- &UpdateEvent{&status}
}
case "notification":
case "delete":
}
default:
}
}
return ctx.Err()
}
func (c *Client) streaming(ctx context.Context, p string, tag string) (chan Event, error) {
u, err := url.Parse(c.config.Server)
if err != nil {
return nil, err
}
u.Path = path.Join(u.Path, "/api/v1/streaming/"+p)
params := url.Values{}
params.Set("tag", tag)
var resp *http.Response
q := make(chan Event, 10)
go func() {
defer ctx.Done()
for {
var in io.Reader
if tag != "" {
in = strings.NewReader(params.Encode())
}
req, err := http.NewRequest(http.MethodGet, u.String(), in)
if err == nil {
req.Header.Set("Authorization", "Bearer "+c.config.AccessToken)
resp, err = c.Do(req)
if resp.StatusCode != 200 {
err = fmt.Errorf("bad request: %v", resp.Status)
}
}
if err == nil {
err = handleReader(ctx, q, resp.Body)
if err == nil {
break
}
} else {
q <- &ErrorEvent{err}
}
resp.Body.Close()
time.Sleep(3 * time.Second)
}
}()
go func() {
<-ctx.Done()
if resp != nil && resp.Body != nil {
resp.Body.Close()
}
}()
return q, nil
}
// StreamingPublic return channel to read events on public.
func (c *Client) StreamingPublic(ctx context.Context) (chan Event, error) {
return c.streaming(ctx, "public", "")
}
// StreamingHome return channel to read events on home.
func (c *Client) StreamingHome(ctx context.Context) (chan Event, error) {
return c.streaming(ctx, "home", "")
}
// StreamingHashtag return channel to read events on tagged timeline.
func (c *Client) StreamingHashtag(ctx context.Context, tag string) (chan Event, error) {
return c.streaming(ctx, "hashtag", tag)
}