Add additional metrics for streaming (#26945)

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Emelia Smith 2023-09-19 12:25:30 +02:00 committed by GitHub
parent 6eb6209d02
commit fbfceb9c77
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@ -152,6 +152,28 @@ const redisConfigFromEnv = (env) => {
};
};
const PUBLIC_CHANNELS = [
'public',
'public:media',
'public:local',
'public:local:media',
'public:remote',
'public:remote:media',
'hashtag',
'hashtag:local',
];
// Used for priming the counters/gauges for the various metrics that are
// per-channel
const CHANNEL_NAMES = [
'system',
'user',
'user:notification',
'list',
'direct',
...PUBLIC_CHANNELS
];
const startServer = async () => {
const app = express();
@ -203,9 +225,6 @@ const startServer = async () => {
labelNames: ['type'],
});
connectedClients.set({ type: 'websocket' }, 0);
connectedClients.set({ type: 'eventsource' }, 0);
const connectedChannels = new metrics.Gauge({
name: 'connected_channels',
help: 'The number of channels the streaming server is streaming to',
@ -217,6 +236,35 @@ const startServer = async () => {
help: 'The number of Redis channels the streaming server is subscribed to',
});
const redisMessagesReceived = new metrics.Counter({
name: 'redis_messages_received_total',
help: 'The total number of messages the streaming server has received from redis subscriptions'
});
const messagesSent = new metrics.Counter({
name: 'messages_sent_total',
help: 'The total number of messages the streaming server sent to clients per connection type',
labelNames: [ 'type' ]
});
// Prime the gauges so we don't loose metrics between restarts:
redisSubscriptions.set(0);
connectedClients.set({ type: 'websocket' }, 0);
connectedClients.set({ type: 'eventsource' }, 0);
// For each channel, initialize the gauges at zero; There's only a finite set of channels available
CHANNEL_NAMES.forEach(( channel ) => {
connectedChannels.set({ type: 'websocket', channel }, 0);
connectedChannels.set({ type: 'eventsource', channel }, 0);
})
// Prime the counters so that we don't loose metrics between restarts.
// Unfortunately counters don't support the set() API, so instead I'm using
// inc(0) to achieve the same result.
redisMessagesReceived.inc(0);
messagesSent.inc({ type: 'websocket' }, 0);
messagesSent.inc({ type: 'eventsource' }, 0);
// When checking metrics in the browser, the favicon is requested this
// prevents the request from falling through to the API Router, which would
// error for this endpoint:
@ -262,6 +310,8 @@ const startServer = async () => {
* @param {string} message
*/
const onRedisMessage = (channel, message) => {
redisMessagesReceived.inc();
const callbacks = subs[channel];
log.silly(`New message on channel ${redisPrefix}${channel}`);
@ -490,17 +540,6 @@ const startServer = async () => {
}
};
const PUBLIC_CHANNELS = [
'public',
'public:media',
'public:local',
'public:local:media',
'public:remote',
'public:remote:media',
'hashtag',
'hashtag:local',
];
/**
* @param {any} req
* @param {string|undefined} channelName
@ -705,10 +744,11 @@ const startServer = async () => {
* @param {any} req
* @param {function(string, string): void} output
* @param {undefined | function(string[], SubscriptionListener): void} attachCloseHandler
* @param {'websocket' | 'eventsource'} destinationType
* @param {boolean=} needsFiltering
* @returns {SubscriptionListener}
*/
const streamFrom = (ids, req, output, attachCloseHandler, needsFiltering = false) => {
const streamFrom = (ids, req, output, attachCloseHandler, destinationType, needsFiltering = false) => {
const accountId = req.accountId || req.remoteAddress;
log.verbose(req.requestId, `Starting stream from ${ids.join(', ')} for ${accountId}`);
@ -717,6 +757,8 @@ const startServer = async () => {
// TODO: Replace "string"-based delete payloads with object payloads:
const encodedPayload = typeof payload === 'object' ? JSON.stringify(payload) : payload;
messagesSent.labels({ type: destinationType }).inc(1);
log.silly(req.requestId, `Transmitting for ${accountId}: ${event} ${encodedPayload}`);
output(event, encodedPayload);
};
@ -1031,7 +1073,7 @@ const startServer = async () => {
const onSend = streamToHttp(req, res);
const onEnd = streamHttpEnd(req, subscriptionHeartbeat(channelIds));
streamFrom(channelIds, req, onSend, onEnd, options.needsFiltering);
streamFrom(channelIds, req, onSend, onEnd, 'eventsource', options.needsFiltering);
}).catch(err => {
log.verbose(req.requestId, 'Subscription error:', err.toString());
httpNotFound(res);
@ -1241,7 +1283,7 @@ const startServer = async () => {
const onSend = streamToWs(request, socket, streamNameFromChannelName(channelName, params));
const stopHeartbeat = subscriptionHeartbeat(channelIds);
const listener = streamFrom(channelIds, request, onSend, undefined, options.needsFiltering);
const listener = streamFrom(channelIds, request, onSend, undefined, 'websocket', options.needsFiltering);
connectedChannels.labels({ type: 'websocket', channel: channelName }).inc();