documentation/streaming/index.js

150 lines
4.3 KiB
JavaScript

import dotenv from 'dotenv'
import express from 'express'
import redis from 'redis'
import pg from 'pg'
import log from 'npmlog'
const env = process.env.NODE_ENV || 'development'
dotenv.config({
path: env === 'production' ? '.env.production' : '.env'
})
const pgConfigs = {
development: {
database: 'mastodon_development',
host: '/var/run/postgresql',
max: 10
},
production: {
user: process.env.DB_USER || 'mastodon',
password: process.env.DB_PASS || '',
database: process.env.DB_NAME || 'mastodon_production',
host: process.env.DB_HOST || 'localhost',
port: process.env.DB_PORT || 5432,
max: 10
}
}
const app = express()
const pgPool = new pg.Pool(pgConfigs[env])
const authenticationMiddleware = (req, res, next) => {
const authorization = req.get('Authorization')
if (!authorization) {
err = new Error('Missing access token')
err.statusCode = 401
return next(err)
}
const token = authorization.replace(/^Bearer /, '')
pgPool.connect((err, client, done) => {
if (err) {
return next(err)
}
client.query('SELECT oauth_access_tokens.resource_owner_id, users.account_id FROM oauth_access_tokens INNER JOIN users ON oauth_access_tokens.resource_owner_id = users.id WHERE oauth_access_tokens.token = $1 LIMIT 1', [token], (err, result) => {
done()
if (err) {
return next(err)
}
if (result.rows.length === 0) {
err = new Error('Invalid access token')
err.statusCode = 401
return next(err)
}
req.accountId = result.rows[0].account_id
next()
})
})
}
const errorMiddleware = (err, req, res, next) => {
log.error(err)
res.writeHead(err.statusCode || 500, { 'Content-Type': 'application/json' })
res.end(JSON.stringify({ error: err.statusCode ? `${err}` : 'An unexpected error occured' }))
}
const placeholders = (arr, shift = 0) => arr.map((_, i) => `$${i + 1 + shift}`).join(', ');
const streamFrom = (id, req, res, needsFiltering = false) => {
log.verbose(`Starting stream from ${id} for ${req.accountId}`)
res.setHeader('Content-Type', 'text/event-stream')
res.setHeader('Transfer-Encoding', 'chunked')
const redisClient = redis.createClient({
host: process.env.REDIS_HOST || '127.0.0.1',
port: process.env.REDIS_PORT || 6379,
password: process.env.REDIS_PASSWORD
})
redisClient.on('message', (channel, message) => {
const { event, payload } = JSON.parse(message)
// Only messages that may require filtering are statuses, since notifications
// are already personalized and deletes do not matter
if (needsFiltering && event === 'update') {
pgPool.connect((err, client, done) => {
if (err) {
log.error(err)
return
}
const unpackedPayload = JSON.parse(payload)
const targetAccountIds = [unpackedPayload.account.id].concat(unpackedPayload.mentions.map(item => item.id)).concat(unpackedPayload.reblog ? [unpackedPayload.reblog.account.id] : [])
client.query(`SELECT target_account_id FROM blocks WHERE account_id = $1 AND target_account_id IN (${placeholders(targetAccountIds, 1)})`, [req.accountId].concat(targetAccountIds), (err, result) => {
done()
if (err) {
log.error(err)
return
}
if (result.rows.length > 0) {
return
}
res.write(`event: ${event}\n`)
res.write(`data: ${payload}\n\n`)
})
})
} else {
res.write(`event: ${event}\n`)
res.write(`data: ${payload}\n\n`)
}
})
const heartbeat = setInterval(() => res.write(':thump\n'), 15000)
req.on('close', () => {
log.verbose(`Ending stream from ${id} for ${req.accountId}`)
clearInterval(heartbeat)
redisClient.quit()
})
redisClient.subscribe(id)
}
app.use(authenticationMiddleware)
app.use(errorMiddleware)
app.get('/api/v1/streaming/user', (req, res) => streamFrom(`timeline:${req.accountId}`, req, res))
app.get('/api/v1/streaming/public', (req, res) => streamFrom('timeline:public', req, res, true))
app.get('/api/v1/streaming/hashtag', (req, res) => streamFrom(`timeline:hashtag:${req.params.tag}`, req, res, true))
log.level = 'verbose'
log.info(`Starting HTTP server on port ${process.env.PORT || 4000}`)
app.listen(process.env.PORT || 4000)