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You will need to enable proxy_wstunnel and modify the OMK provided Apache virtual host.

The minimum Apache version required is 2.4.5

Debian

If you are running a debian based linux os please enable these apache modules

a2enmod proxy
a2enmod proxy_http
a2enmod proxy_wstunnel

CentOS & Redhat 7

Edit /etc/httpd/conf.modules.d/00-proxy.conf

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ProxyPass "/en/omk/opEvents/ws/events" ws://localhost:8042/en/omk/opEvents/ws/events

Proxy the websocket for Redhat 7

This has been tested with Apache 2.4.6

Instead of ProxyPass you will need to use ProxyPassMatch

ProxyPassMatch ^/(en/omk/opEvents/ws/events)$  ws://localhost:8042/$1

A basic example with config to use serve opEvents over SSL and proxy the Webscockets

<VirtualHost *:443>
        ServerName example.opmantek.com

        SSLEngine on
        SSLProxyEngine On
        ProxyRequests Off

        SSLCertificateFile    /etc/ssl/certs/example/cert.pem
        SSLCertificateKeyFile /etc/ssl/certs/example/privkey.pem
        SSLCertificateChainFile /etc/ssl/certs/example/fullchain.pem

        RequestHeader set X-Forwarded-Proto "https"

		# Proxy the websocket connection
        ProxyPassMatch ^/(en/omk/opEvents/ws/events)$  ws://localhost:8042/$1
		# Proxy the rest of the application
        ProxyPass / http://localhost:8042/
        ProxyPassReverse / http://localhost:8042/

</VirtualHost>

Debugging Web Socket connections

If you see this error it means the browser cannot connect to the webserver, at this current point you will need to use the Browsers developments tools to access the Javascript Console

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Uncaught DomException: The operation is insecure

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You are serving opEvents over ssl but the websocket is trying to to connect over http, this is disallowed from happening because of browser security policies.

You will need to find your Apache Config and make sure this header is being sent to the omkd web server

RequestHeader set X-Forwarded-Proto "https"

Get /en/omk/opEvents/ws/events 404 Not Found

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The websocket is trying to connect securely but its not being proxied correctly, please see the above section Proxy the webscocket

Check Apache has proxy_wstunnel_module loaded

httpd  -t -D DUMP_MODULES | grep proxy_wstunnel_module

 (shared)Current Issues

Event partial updates over websockets eg {id:abc, acknowledged:1} have no group check, meaning if you have a user with only group access of "DataCenter" their browsers websocket would receive partial updates from events their group permission would not allow access to. As the users browsers doesn't have the original event the partial update will not be shown to the user. This is planned to be fixed in the next release.

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