package streaming import ( "fmt" "net/http" "time" "github.com/gin-gonic/gin" "github.com/gorilla/websocket" ) // StreamGETHandler swagger:operation GET /api/v1/streaming streamGet // // Initiate a websocket connection for live streaming of statuses and notifications. // // The scheme used should *always* be `wss`. The streaming basepath can be viewed at `/api/v1/instance`. // // On a successful connection, a code `101` will be returned, which indicates that the connection is being upgraded to a secure websocket connection. // // As long as the connection is open, various message types will be streamed into it. // // GoToSocial will ping the connection every 30 seconds to check whether the client is still receiving. // // If the ping fails, or something else goes wrong during transmission, then the connection will be dropped, and the client will be expected to start it again. // // --- // tags: // - streaming // // produces: // - application/json // // schemes: // - wss // // parameters: // - name: access_token // type: string // description: Access token for the requesting account. // in: query // required: true // - name: stream // type: string // description: |- // Type of stream to request. // // Options are: // // `user`: receive updates for the account's home timeline. // `public`: receive updates for the public timeline. // `public:local`: receive updates for the local timeline. // `hashtag`: receive updates for a given hashtag. // `hashtag:local`: receive local updates for a given hashtag. // `list`: receive updates for a certain list of accounts. // `direct`: receive updates for direct messages. // in: query // required: true // security: // - OAuth2 Bearer: // - read:streaming // // responses: // '101': // schema: // type: object // properties: // stream: // type: array // items: // type: string // enum: // - user // - public // - public:local // - hashtag // - hashtag:local // - list // - direct // event: // description: |- // The type of event being received. // // `update`: a new status has been received. // `notification`: a new notification has been received. // `delete`: a status has been deleted. // `filters_changed`: not implemented. // type: string // enum: // - update // - notification // - delete // - filters_changed // payload: // description: |- // The payload of the streamed message. // Different depending on the `event` type. // // If present, it should be parsed as a string. // // If `event` = `update`, then the payload will be a JSON string of a status. // If `event` = `notification`, then the payload will be a JSON string of a notification. // If `event` = `delete`, then the payload will be a status ID. // type: string // example: "{\"id\":\"01FC3TZ5CFG6H65GCKCJRKA669\",\"created_at\":\"2021-08-02T16:25:52Z\",\"sensitive\":false,\"spoiler_text\":\"\",\"visibility\":\"public\",\"language\":\"en\",\"uri\":\"https://gts.superseriousbusiness.org/users/dumpsterqueer/statuses/01FC3TZ5CFG6H65GCKCJRKA669\",\"url\":\"https://gts.superseriousbusiness.org/@dumpsterqueer/statuses/01FC3TZ5CFG6H65GCKCJRKA669\",\"replies_count\":0,\"reblogs_count\":0,\"favourites_count\":0,\"favourited\":false,\"reblogged\":false,\"muted\":false,\"bookmarked\":fals…//gts.superseriousbusiness.org/fileserver/01JNN207W98SGG3CBJ76R5MVDN/header/original/019036W043D8FXPJKSKCX7G965.png\",\"header_static\":\"https://gts.superseriousbusiness.org/fileserver/01JNN207W98SGG3CBJ76R5MVDN/header/small/019036W043D8FXPJKSKCX7G965.png\",\"followers_count\":33,\"following_count\":28,\"statuses_count\":126,\"last_status_at\":\"2021-08-02T16:25:52Z\",\"emojis\":[],\"fields\":[]},\"media_attachments\":[],\"mentions\":[],\"tags\":[],\"emojis\":[],\"card\":null,\"poll\":null,\"text\":\"a\"}" // '401': // description: unauthorized // '400': // description: bad request func (m *Module) StreamGETHandler(c *gin.Context) { l := m.log.WithField("func", "StreamGETHandler") streamType := c.Query(StreamQueryKey) if streamType == "" { c.JSON(http.StatusBadRequest, gin.H{"error": fmt.Sprintf("no stream type provided under query key %s", StreamQueryKey)}) return } accessToken := c.Query(AccessTokenQueryKey) if accessToken == "" { c.JSON(http.StatusUnauthorized, gin.H{"error": fmt.Sprintf("no access token provided under query key %s", AccessTokenQueryKey)}) return } // make sure a valid token has been provided and obtain the associated account account, err := m.processor.AuthorizeStreamingRequest(accessToken) if err != nil { c.JSON(http.StatusUnauthorized, gin.H{"error": "could not authorize with given token"}) return } // prepare to upgrade the connection to a websocket connection upgrader := websocket.Upgrader{ ReadBufferSize: 1024, WriteBufferSize: 1024, CheckOrigin: func(r *http.Request) bool { // we fully expect cors requests (via something like pinafore.social) so we should be lenient here return true }, } // do the actual upgrade here conn, err := upgrader.Upgrade(c.Writer, c.Request, nil) if err != nil { l.Infof("error upgrading websocket connection: %s", err) return } defer conn.Close() // whatever happens, when we leave this function we want to close the websocket connection // inform the processor that we have a new connection and want a stream for it stream, errWithCode := m.processor.OpenStreamForAccount(account, streamType) if errWithCode != nil { c.JSON(errWithCode.Code(), errWithCode.Safe()) return } defer close(stream.Hangup) // closing stream.Hangup indicates that we've finished with the connection (the client has gone), so we want to do this on exiting this handler // spawn a new ticker for pinging the connection periodically t := time.NewTicker(30 * time.Second) // we want to stay in the sendloop as long as possible while the client is connected -- the only thing that should break the loop is if the client leaves or something else goes wrong sendLoop: for { select { case m := <-stream.Messages: // we've got a streaming message!! l.Trace("received message from stream") if err := conn.WriteJSON(m); err != nil { l.Debugf("error writing json to websocket connection: %s", err) // if something is wrong we want to bail and drop the connection -- the client will create a new one break sendLoop } l.Trace("wrote message into websocket connection") case <-t.C: l.Trace("received TICK from ticker") if err := conn.WriteMessage(websocket.PingMessage, []byte(": ping")); err != nil { l.Debugf("error writing ping to websocket connection: %s", err) // if something is wrong we want to bail and drop the connection -- the client will create a new one break sendLoop } l.Trace("wrote ping message into websocket connection") } } l.Trace("leaving StreamGETHandler") }