diff options
author | Eugen Rochko <eugen@zeonfederated.com> | 2017-02-07 14:37:12 +0100 |
---|---|---|
committer | Eugen Rochko <eugen@zeonfederated.com> | 2017-02-07 14:39:08 +0100 |
commit | 02e91a96ddded6f6d2505f80b45705fcfb77ed74 (patch) | |
tree | dfdd4be3ce21869fa6611e41f763b6fab3ca7a95 /streaming | |
parent | 9d5fb49cd80ee31f83bf5364338bd829e3eae1d6 (diff) |
Make streaming API use one pattern-matching redis pubsub connection
Refresh timelines when streaming API reconnects in the UI
Diffstat (limited to 'streaming')
-rw-r--r-- | streaming/index.js | 94 |
1 files changed, 63 insertions, 31 deletions
diff --git a/streaming/index.js b/streaming/index.js index e2e8f943e71..125b35bb44f 100644 --- a/streaming/index.js +++ b/streaming/index.js @@ -36,6 +36,39 @@ const pgPool = new pg.Pool(pgConfigs[env]) const server = http.createServer(app) const wss = new WebSocket.Server({ server }) +const redisClient = redis.createClient({ + host: process.env.REDIS_HOST || '127.0.0.1', + port: process.env.REDIS_PORT || 6379, + password: process.env.REDIS_PASSWORD +}) + +const subs = {} + +redisClient.on('pmessage', (_, channel, message) => { + const callbacks = subs[channel] + + log.silly(`New message on channel ${channel}`) + + if (!callbacks) { + return + } + + callbacks.forEach(callback => callback(message)) +}) + +redisClient.psubscribe('timeline:*') + +const subscribe = (channel, callback) => { + log.silly(`Adding listener for ${channel}`) + subs[channel] = subs[channel] || [] + subs[channel].push(callback) +} + +const unsubscribe = (channel, callback) => { + log.silly(`Removing listener for ${channel}`) + subs[channel] = subs[channel].filter(item => item !== callback) +} + const allowCrossDomain = (req, res, next) => { res.header('Access-Control-Allow-Origin', '*') res.header('Access-Control-Allow-Headers', 'Authorization, Accept, Cache-Control') @@ -105,10 +138,10 @@ const errorMiddleware = (err, req, res, next) => { const placeholders = (arr, shift = 0) => arr.map((_, i) => `$${i + 1 + shift}`).join(', '); -const streamFrom = (redisClient, id, req, output, needsFiltering = false) => { +const streamFrom = (id, req, output, attachCloseHandler, needsFiltering = false) => { log.verbose(req.requestId, `Starting stream from ${id} for ${req.accountId}`) - redisClient.on('message', (channel, message) => { + const listener = message => { const { event, payload, queued_at } = JSON.parse(message) const transmit = () => { @@ -149,13 +182,14 @@ const streamFrom = (redisClient, id, req, output, needsFiltering = false) => { } else { transmit() } - }) + } - redisClient.subscribe(id) + subscribe(id, listener) + attachCloseHandler(id, listener) } // Setup stream output to HTTP -const streamToHttp = (req, res, redisClient) => { +const streamToHttp = (req, res) => { res.setHeader('Content-Type', 'text/event-stream') res.setHeader('Transfer-Encoding', 'chunked') @@ -164,7 +198,6 @@ const streamToHttp = (req, res, redisClient) => { req.on('close', () => { log.verbose(req.requestId, `Ending stream for ${req.accountId}`) clearInterval(heartbeat) - redisClient.quit() }) return (event, payload) => { @@ -173,11 +206,17 @@ const streamToHttp = (req, res, redisClient) => { } } +// Setup stream end for HTTP +const streamHttpEnd = req => (id, listener) => { + req.on('close', () => { + unsubscribe(id, listener) + }) +} + // Setup stream output to WebSockets -const streamToWs = (req, ws, redisClient) => { +const streamToWs = (req, ws) => { ws.on('close', () => { log.verbose(req.requestId, `Ending stream for ${req.accountId}`) - redisClient.quit() }) return (event, payload) => { @@ -190,12 +229,12 @@ const streamToWs = (req, ws, redisClient) => { } } -// Get new redis connection -const getRedisClient = () => redis.createClient({ - host: process.env.REDIS_HOST || '127.0.0.1', - port: process.env.REDIS_PORT || 6379, - password: process.env.REDIS_PASSWORD -}) +// Setup stream end for WebSockets +const streamWsEnd = ws => (id, listener) => { + ws.on('close', () => { + unsubscribe(id, listener) + }) +} app.use(setRequestId) app.use(allowCrossDomain) @@ -203,28 +242,23 @@ app.use(authenticationMiddleware) app.use(errorMiddleware) app.get('/api/v1/streaming/user', (req, res) => { - const redisClient = getRedisClient() - streamFrom(redisClient, `timeline:${req.accountId}`, req, streamToHttp(req, res, redisClient)) + streamFrom(`timeline:${req.accountId}`, req, streamToHttp(req, res), streamHttpEnd(req)) }) app.get('/api/v1/streaming/public', (req, res) => { - const redisClient = getRedisClient() - streamFrom(redisClient, 'timeline:public', req, streamToHttp(req, res, redisClient), true) + streamFrom('timeline:public', req, streamToHttp(req, res), streamHttpEnd(req), true) }) app.get('/api/v1/streaming/public/local', (req, res) => { - const redisClient = getRedisClient() - streamFrom(redisClient, 'timeline:public:local', req, streamToHttp(req, res, redisClient), true) + streamFrom('timeline:public:local', req, streamToHttp(req, res), streamHttpEnd(req), true) }) app.get('/api/v1/streaming/hashtag', (req, res) => { - const redisClient = getRedisClient() - streamFrom(redisClient, `timeline:hashtag:${req.params.tag}`, req, streamToHttp(req, res, redisClient), true) + streamFrom(`timeline:hashtag:${req.params.tag}`, req, streamToHttp(req, res), streamHttpEnd(req), true) }) app.get('/api/v1/streaming/hashtag/local', (req, res) => { - const redisClient = getRedisClient() - streamFrom(redisClient, `timeline:hashtag:${req.params.tag}:local`, req, streamToHttp(req, res, redisClient), true) + streamFrom(`timeline:hashtag:${req.params.tag}:local`, req, streamToHttp(req, res), streamHttpEnd(req), true) }) wss.on('connection', ws => { @@ -239,23 +273,21 @@ wss.on('connection', ws => { return } - const redisClient = getRedisClient() - switch(location.query.stream) { case 'user': - streamFrom(redisClient, `timeline:${req.accountId}`, req, streamToWs(req, ws, redisClient)) + streamFrom(`timeline:${req.accountId}`, req, streamToWs(req, ws), streamWsEnd(ws)) break; case 'public': - streamFrom(redisClient, 'timeline:public', req, streamToWs(req, ws, redisClient), true) + streamFrom('timeline:public', req, streamToWs(req, ws), streamWsEnd(ws), true) break; case 'public:local': - streamFrom(redisClient, 'timeline:public:local', req, streamToWs(req, ws, redisClient), true) + streamFrom('timeline:public:local', req, streamToWs(req, ws), streamWsEnd(ws), true) break; case 'hashtag': - streamFrom(redisClient, `timeline:hashtag:${location.query.tag}`, req, streamToWs(req, ws, redisClient), true) + streamFrom(`timeline:hashtag:${location.query.tag}`, req, streamToWs(req, ws), streamWsEnd(ws), true) break; case 'hashtag:local': - streamFrom(redisClient, `timeline:hashtag:${location.query.tag}:local`, req, streamToWs(req, ws, redisClient), true) + streamFrom(`timeline:hashtag:${location.query.tag}:local`, req, streamToWs(req, ws), streamWsEnd(ws), true) break; default: ws.close() |