%docentities; ]> &adminguide;
Overview 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.
Dependencies
&kamailio; Modules The following modules must be loaded before this module: tm - (optional) needed only by evapi_async_relay()
External Libraries or Applications The following libraries or applications must be installed before running &kamailio; with this module loaded: libev - http://software.schmorp.de/pkg/libev.html
Parameters
<varname>workers</varname> (int) Number of worker processes to be started to handle incoming messages from remote applications. Default value is 1. Set <varname>workers</varname> parameter ... modparam("evapi", "workers", 2) ...
<varname>bind_addr</varname> (str) Local IP and port to listen on for incoming TCP connections. Default value is "127.0.0.1:8448". Set <varname>bind_addr</varname> parameter ... modparam("evapi", "bind_addr", "1.2.3.4:8228") ...
<varname>netstring_format</varname> (int) Control if messages on the socket (to and from clients) are encapsulated in netstring format. Default value is 1 (netstring format). Set <varname>netstring_format</varname> parameter ... modparam("evapi", "netstring_format", 0) ...
Functions
<function moreinfo="none">evapi_relay(evdata)</function> 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. <function>evapi_relay</function> usage ... evapi_relay("{ \"event\": \"test\",\n \"data\": { \"fU\": \"$fU\" }\n}"); ... The above exaple will send the following message over tcp: TCP message ... 47:{ "event": "test", "data": { "fU": "test" } }, ...
<function moreinfo="none">evapi_async_relay(evdata)</function> Relay the event data given as parameter to connected applications. Before evaluating the parameter, the request processing is suspended using tm module (using the t_suspend()/t_continue() framework). The routing of the SIP request can be continued once event_route[evapi:message-received] is triggered. After evapi_async_relay() returns true, no relaying should happen in request_route(), it should be followed by exit;. The format on the network is netstring with evdata payload if netstring_format parameter is set to 1 or bare evdata if netstring_format parameter is set to 0. This function can be used from REQUEST_ROUTE. <function>evapi_async_relay</function> usage ... evapi_async_relay("{ \"event\": \"suspend\",\n \"data\":" " { \"index\": \"$T(id_index)\", \"label\": \"$T(id_label)\" }\n}"); ...
<function moreinfo="none">evapi_close()</function> Close evapi current client connection. This function can be used from ANY_ROUTE. <function>evapi_evapi</function> usage ... event_route[evapi:connection-new] { if($evapi(srcaddr)!="127.0.0.1") { evapi_close(); exit; } } ...
Event routes
<function moreinfo="none">evapi:connection-new</function> 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"); } ...
<function moreinfo="none">evapi:connection-closed</function> 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"); } ...
<function moreinfo="none">evapi:message-received</function> If defined, the module calls event_route[evapi:message-received] when a message is received from a client. ... event_route[evapi:message-received] { xlog("received [$evapi(msg)] from $evapi(srcaddr):$evapi(srcport)\n"); } ...
Exported pseudo-variables $evapi(srcaddr) - source ip $evapi(srcport) - source port $evapi(msg) - received event message $evapi(conidx) - internal connection index Exported pseudo-variables are documented at &kamwikilink;.