Table of Contents
List of Examples
workers parameterbind_addr parameternetstring_format parameterevent_callback parametermax_clients parameterevapi_relay usageevapi_async_relay usageevapi_multicast usageevapi_async_multicast usageevapi_unicast usageevapi_async_unicast usageevapi_close usageevapi_set_tag usageTable of Contents
The EVAPI module can be used to create an event message flow from Kamailio to any application that can connect to a TCP socket. The remote application can also issue messages received by Kamailio.
There is no protocol definition, it is all up to the author of the routing script. Events can be generated for any event in Kamailio. For 3rd party transaction control, a transaction can be automatically suspended when sending the event, to be resumed at a later point, maybe triggered by an incoming message on the event socket.
The following modules must be loaded before this module:
tm - (optional) needed only by evapi_async_relay()
The following libraries or applications must be installed before running Kamailio with this module loaded:
Number of worker processes to be started to handle incoming messages from remote applications.
Default value is 1.
Local IP and port to listen on for incoming TCP connections.
Default value is "127.0.0.1:8448".
Control if messages on the socket (to and from clients) are encapsulated in netstring format.
Default value is 1 (netstring format).
The name of the function in the kemi configuration file (embedded scripting language such as Lua, Python, ...) to be executed instead of event_route[...] blocks.
The function receives a string parameter with the name of the event, the values are: 'evapi:connection-new', 'evapi:connection-closed', 'evapi:message-received'.
Default value is 'empty' (no function is executed for events).
Example 1.4. Set event_callback parameter
...
modparam("evapi", "event_callback", "ksr_evapi_event")
...
-- event callback function implemented in Lua
function ksr_evapi_event(evname)
KSR.info("===== evapi module triggered event: " .. evname .. "\n");
return 1;
end
...
Relay the event data given as parameter to connected applications.
The format on the network is netstring with evdata payload if netstring_format parameter is set to 1 or bare evdata if netstring_format parameter is set to 0.
The function is passing the task to evapi dispatcher process, therefore the SIP worker process is not blocked. Also, it doesn't wait for any response, therefore the processing of the configuration continues very fast when executing evapi_relay().
This function can be used from ANY_ROUTE.
Example 1.6. evapi_relay usage
...
evapi_relay("{ \"event\": \"test\",\n \"data\": { \"fU\": \"$fU\" }\n}");
...
The above exaple will send the following message over tcp:
Relay the event data given as parameter to connected applications. Before evaluating the parameter, the request processing is suspended using tm module (using the t_suspend()/t_continue() framework). The routing of the SIP request can be continued once event_route[evapi:message-received] is triggered. After evapi_async_relay() returns true, no relaying should happen in request_route(), it should be followed by exit;.
The format on the network is netstring with evdata payload if netstring_format parameter is set to 1 or bare evdata if netstring_format parameter is set to 0.
This function can be used from REQUEST_ROUTE.
Example 1.8. evapi_async_relay usage
...
evapi_async_relay("{ \"event\": \"suspend\",\n \"data\":"
" { \"index\": \"$T(id_index)\", \"label\": \"$T(id_label)\" }\n}");
...
Relay the event data given as parameter to connections that match the tag provided by etag value. The etag can be a variable. For more see evapi_relay() and evapi_set_tag().
Example 1.9. evapi_multicast usage
...
evapi_multicast("{ \"event\": \"test\",\n \"data\": { \"fU\": \"$fU\" }\n}", "tagx");
...
Async relay the event data given as parameter to connections that match the tag provided by etag value. The etag can be a variable. For more see evapi_async_relay() and evapi_set_tag().
Example 1.10. evapi_async_multicast usage
...
evapi_async_multicast("{ \"event\": \"suspend\",\n \"data\":"
" { \"index\": \"$T(id_index)\", \"label\": \"$T(id_label)\" }\n}", "tagx");
...
Relay the event data given as parameter to the first connection that match the tag provided by etag value. The etag can be a variable. For more see evapi_relay() and evapi_set_tag().
Example 1.11. evapi_unicast usage
...
evapi_unicast("{ \"event\": \"test\",\n \"data\": { \"fU\": \"$fU\" }\n}", "tagx");
...
Async relay the event data given as parameter to the first connection that match the tag provided by etag value. The etag can be a variable. For more see evapi_async_relay() and evapi_set_tag().
Example 1.12. evapi_async_unicast usage
...
evapi_async_unicast("{ \"event\": \"suspend\",\n \"data\":"
" { \"index\": \"$T(id_index)\", \"label\": \"$T(id_label)\" }\n}", "tagx");
...
Close evapi current client connection.
This function can be used from ANY_ROUTE.
Example 1.13. evapi_close usage
...
event_route[evapi:connection-new] {
if($evapi(srcaddr)!="127.0.0.1") {
evapi_close();
exit;
}
}
...
Set tag name for current client connection. The parameters has to be a string up to 64 characters. It can also be a variable holding such string.
This function can be used from ANY_ROUTE.
Example 1.14. evapi_set_tag usage
...
event_route[evapi:connection-new] {
if($evapi(srcaddr)=="127.0.0.1") {
evapi_set_tag("local");
exit;
}
}
...
If defined, the module calls event_route[evapi:connection-new] when a new client is connected.
...
event_route[evapi:connection-new] {
xlog("new connection from $evapi(srcaddr):$evapi(srcport)\n");
}
...
If defined, the module calls event_route[evapi:connection-closed] when a client connection is closed.
...
event_route[evapi:connection-closed] {
xlog("connection closed by $evapi(srcaddr):$evapi(srcport)\n");
}
...
$evapi(srcaddr) - source ip
$evapi(srcport) - source port
$evapi(msg) - received event message
$evapi(conidx) - internal connection index
Exported pseudo-variables are documented at https://www.kamailio.org/wiki/.