Mercurial > prosody-modules
annotate mod_pubsub_eventsource/README.markdown @ 5951:d6a695abb33c
mod_ping_muc: Delay ping a configurable amount of time
If a server is restarting, checking immediately before it has a chance
to complete its restart and get ready would often fail, preventing the
possibility of transparent restarts as supported by Prosody's mod_muc.
Reconnecting immediately when a connection is closed for being idle, or
because the remote server is trying to reclaim some resources, is also
counter-productive as the connection may fail.
Also, if there is some Internet routing problem affecting s2s, it may
help to wait a bit before checking, in case the problem resolved itself
in the mean time.
| author | Kim Alvefur <zash@zash.se> |
|---|---|
| date | Sun, 11 Aug 2024 16:10:24 +0200 |
| parents | 694b62d8a82f |
| children |
| rev | line source |
|---|---|
| 1803 | 1 --- |
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694b62d8a82f
various/README: Fix 'labels' metadata, should be a list
Kim Alvefur <zash@zash.se>
parents:
1803
diff
changeset
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2 labels: |
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694b62d8a82f
various/README: Fix 'labels' metadata, should be a list
Kim Alvefur <zash@zash.se>
parents:
1803
diff
changeset
|
3 - Stage-Beta |
| 1803 | 4 summary: Subscribe to pubsub nodes using the HTML5 EventSource API |
| 5 ... | |
| 6 | |
| 7 Introduction | |
| 8 ------------ | |
| 9 | |
| 10 [Server-Sent Events](https://en.wikipedia.org/wiki/Server-sent_events) | |
| 11 is a simple HTTP/line-based protocol supported in HTML5, making it easy | |
| 12 to receive a stream of "events" in realtime using the Javascript | |
| 13 [EventSource | |
| 14 API](https://developer.mozilla.org/en-US/docs/Web/API/EventSource). | |
| 15 | |
| 16 EventSource is supported in [most modern | |
| 17 browsers](http://caniuse.com/#feat=eventsource), and for the remainder | |
| 18 there are 'polyfill' compatibility layers such as | |
| 19 [EventSource.js](https://github.com/remy/polyfills/blob/master/EventSource.js) | |
| 20 and [jquery.eventsource](https://github.com/rwldrn/jquery.eventsource). | |
| 21 | |
| 22 Details | |
| 23 ------- | |
| 24 | |
| 25 Subscribing to a node from Javascript is easy: | |
| 26 | |
| 27 var source = new EventSource('http://pubsub.example.org:5280/eventsource/mynode'); | |
| 28 source.onmessage = function (event) { | |
| 29 console.log(event.data); // Do whatever you want with the data here | |
| 30 }; | |
| 31 | |
| 32 ### Cross-domain issues | |
| 33 | |
| 34 The same cross-domain restrictions apply to EventSource that apply to | |
| 35 BOSH, and support for CORS is not clearly standardized yet. You may want | |
| 36 to proxy connections through your web server for this reason. See [BOSH: | |
| 37 Cross-domain | |
| 38 issues](https://prosody.im/doc/setting_up_bosh#proxying_requests) for | |
| 39 more information. | |
| 40 | |
| 41 Configuration | |
| 42 ------------- | |
| 43 | |
| 44 There is no special configuration for this module. Simply load it onto a | |
| 45 pubsub component like so: | |
| 46 | |
| 47 Component "pubsub.example.org" "pubsub" | |
| 48 modules_enabled = { "pubsub_eventsource" } | |
| 49 | |
| 50 As it uses HTTP to serve the event streams, you can use Prosody's | |
| 51 standard [HTTP configuration options](https://prosody.im/doc/http) to | |
| 52 control how/where the streams are served. | |
| 53 | |
| 54 **Note about URLs:** It is important to get the event streams from the | |
| 55 correct hostname (that of the pubsub host). An example stream URL is | |
| 56 `http://pubsub.example.org:5280/eventsource/mynode`. If you need to | |
| 57 access the streams using another hostname (e.g. `example.org`) you can | |
| 58 use the `http_host` option under the Component, e.g. | |
| 59 `http_host = "example.org"`. For more information see the ['Virtual | |
| 60 Hosts'](https://prosody.im/doc/http#virtual_hosts) section of our HTTP | |
| 61 documentation. | |
| 62 | |
| 63 Compatibility | |
| 64 ------------- | |
| 65 | |
| 66 ------- -------------- | |
| 67 0.9 Works | |
| 68 0.8 Doesn't work | |
| 69 Trunk Works | |
| 70 ------- -------------- |