HT-TAPI Hyper-Text Telephony API and http file format plugin

This module provides an HTTP based Telephony API using a standard FreeSWITCH application interface as well as a cached http file format interface.

The file format plugin can be used like this:
<action application="playback" data="http://some.com/sounds/foo.wav"/>

This syntax is valid anywhere a filename parameter is requested in FreeSWITCH.


The application is called like this:

<action application="httapi" data="{url=http://some.host.com/app.cgi}"/>

The target url is expected to be a CGI returning text/xml using the documentation below.

The format is roughly as described below (We could use a DTD maybe).

<document type="xml/freeswitch-httapi">
  <params>
   <someparam>someval</someparam>
  </params>
  <variables>
   <somevar>someval</somevar>
  </variables>
  <work>
  <...>
  </work>
</document>


The profile name must be chosen to bind to a preset series of settings and permissions to use as a basis for the client session.
It's chosen from the specified params or from the channel variable using the keyname 'httapi_profile' and if not specified will default to 'default'
Any params specified in the initial data of the application encased in brackets {} will be parsed into the initial params similar to originate.
These params remain set until the call ends and are supplied as form elements on each hit to the HTTP server.
If the permissions allow, a <params> tag is parsed from the resulting document and set into this data set and will be mirrored back on subsequqent http posts.
Also if the permissions allow a <variables> tag is parsed the same way setting channel variables.
The <work> tag is required and contains one or more of the supported command tags that generally manipulate the call behaviour.
The application will continue to do the task in the work section until an error is encoutered or when an action from the work tag warrants it.
If the session exits the httapi app without hanging up it can do other tasks and make another call to httapi and the session data will remain preserved.


EXAMPLE:

<document type="xml/freeswitch-httapi">
<params></params>
<work>
<playback name="exten" file="http://my.com/sounds/exten.wav" error-file="http://my.com/sounds/invalid.wav" input-timeout="5000">
<bind strip="#">~\d+#</bind>
</playback>
</work>
</document>

BINDINGS
Several of the work tags that indicate they support bindings can contain one of more bind tags that function with similar fashion to bind_digit_action

<bind action strip>*EXPR*</bind>

ATTRS:
action              : a specific url to go to next if the binding is dialed
strip               : a character to strip from in the result such as #

WORK TAGS:
<work>*ACTIONS*</work>


<playback file name error-file action digit-timeout input-timeout loops asr-engine asr-grammar><bind action strip>*EXPR*</bind></playback>
		    : Plays a file and optionally collects input.

ATTRS:
file                : The file
name                : Param name to save result.
error-file          : Error file to play on invalid input.
action              : Change the new target url.
temp-action	    : Change url to submit to. just for the next loop.
digit-timeout       : Timeout waiting for digits after file plays (when input bindings are present)
input-timeout       : Timeout waiting for more digits in a multi-digit input.
loops               : max times to play the file when input bindings are present.
asr-engine          : ASR engine to use
asr-grammar         : ASR grammar to use


<vmname file name action digit-timeout input-timeout loops><bind action strip>*EXPR*</bind></playback>
		    : Plays a vm name and optionally collects input.

ATTRS:
file                : The file
name                : Param name to save result.
error-file          : Error file to play on invalid input.
action              : Change the new target url.
temp-action	    : Change url to submit to. just for the next loop.
digit-timeout       : Timeout waiting for digits after file plays (when input bindings are present)
input-timeout       : Timeout waiting for more digits in a multi-digit input.
loops               : max times to play the file when input bindings are present.





<record file name error-file action digit-timeout input-timeout><bind action strip>*EXPR*</bind></record>
		    : Records a file, optionally collects input and posts the file back to the target url.

ATTRS:
file                : The file
name                : Param name to save result.
error-file          : Error file to play on invalid input.
action              : Change the new target url.
temp-action	    : Change url to submit to. just for the next loop.
digit-timeout       : Timeout waiting for digits after file plays (when input bindings are present)
input-timeout       : Timeout waiting for more digits in a multi-digit input.





<pause name error-file action digit-timeout input-timeout loops milliseconds><bind action strip>*EXPR*</bind></pause>
		    : Waits for input for a specific amount of time.

ATTRS:
milliseconds        : Number of milliseconds to pause
name                : Param name to save result.
error-file          : Error file to play on invalid input.
action              : Change the new target url.
temp-action	    : Change url to submit to. just for the next loop.
digit-timeout       : Timeout waiting for digits after file plays (when input bindings are present)
input-timeout       : Timeout waiting for more digits in a multi-digit input.
loops               : max times to play the file when input bindings are present.





<speak file name error-file action digit-timeout input-timeout loops engine voice><bind action strip>*EXPR*</bind></speak>
		    : Read Text to Speech with optional input.

ATTRS:
file                : The file
name                : Param name to save result.
error-file          : Error file to play on invalid input.
action              : Change the new target url.
temp-action	    : Change url to submit to. just for the next loop.
digit-timeout       : Timeout waiting for digits after file plays (when input bindings are present)
input-timeout       : Timeout waiting for more digits in a multi-digit input.
loops               : max times to play the file when input bindings are present.
engine              : tts engine to use.
voice               : tts voice to use.





<say file name error-file action digit-timeout input-timeout loops language type method gender><bind action strip>*EXPR*</bind></say>
		    : Use the FS say engine to iterate sounds to similate a human speaker.

ATTRS:
file                : The file
name                : Param name to save result.
error-file          : Error file to play on invalid input.
action              : Change the new target url.
temp-action	    : Change url to submit to. just for the next loop.
digit-timeout       : Timeout waiting for digits after file plays (when input bindings are present)
input-timeout       : Timeout waiting for more digits in a multi-digit input.
loops               : max times to play the file when input bindings are present.
language            : language
type                : type (fs param)
method              : method (fs param)
gender              : gender (fs param)





<execute application data action>*DATA*</execute>
		    : Execute a FreeSWITCH app.
ATTRS:
application         : The app to run
action		    : Change url to submit to.
temp-action	    : Change url to submit to. just for the next loop.
data		    : Alternate source for app data
*DATA*              : The app data



<sms to action>DATA</sms>
		    : Send a SMS message.
ATTRS:
to                  : The dest number
action		    : Change url to submit to.
temp-action	    : Change url to submit to. just for the next loop.
*DATA*              : The message data





<dial context dialplan caller-id-name caller-id-number action>*DATA*</dial>
		    : Place an outbound call or transfer.

ATTRS:
context             : Dialplan context.
dialplan            : Dialplan dialplan.
caller-id-name      : Caller ID Name.
caller-id-number    : Caller ID Number.
action		    : Change url to submit to.
temp-action	    : Change url to submit to. just for the next loop.
*DATA*              : Number to dial or originate string





<recordCall limit name action>
		    : begin recording the call.  The file will be posted when the call ends.

ATTRS:
limit               : Timeout in seconds.
name                : Name to use for input values.
action              : URL action to use.
temp-action	    : Change url to submit to. just for the next loop.




<conference profile action>
		    : Start a conference call.

ATTRS:
profile             : Conference profile to use.
action		    : Change url to submit to.
temp-action	    : Change url to submit to. just for the next loop.



<hangup cause action>
		    : Hangup the call

ATTRS:
cause               : Hangup cause
action		    : Change url to submit to.
temp-action	    : Change url to submit to. just for the next loop.



<break>
		    : Exit the httapi application and continue in the dialplan.





<log level clean action>
		    : Write a log line to fs_cli, console, logs, etc.
ATTRS:
level               : The log level to use.
clean               : If true do not print log prefix.
action		    : Change url to submit to.
temp-action	    : Change url to submit to. just for the next loop.

<continue action>
                    : Just continue (no-op)

ATTRS:
action		    : Change url to submit to.
temp-action	    : Change url to submit to. just for the next loop.


<getVar action temp-action permanent/>
                    : Get a Channel variable (depends on permissions)

ATTRS:
action		    : Change url to submit to.
temp-action	    : Change url to submit to. just for the next loop.
permanent	    : Add as a permanent param or just once.


<voicemail action temp-action check auth-only profile domain id/>
                    : Call the voicemail app without requiring "execute" permissions

ATTRS:
action		    : Change url to submit to.
temp-action	    : Change url to submit to. just for the next loop.
check		    : true to check (omit to leave)
auth-only	    : authenticate only and move on
profile		    : profile name to use (omit for "default")
domain		    : domain to use (omit for global domain variable)
id		    : id to use (omit to prompt for id)





CONFIGURATION:

<settings>:
<param name="" value="">
debug                           : <true|false>          false           Print debug data
file-cache-ttl                  : <number of sec>       300             How long to wait before checking the server to see if audio file has changed.
file-not-found-expires          : <number of sec>       300             How long to still preserve cached audio files that are not found by the server.

<profile name="<name>">         : CREATE NEW PROFILE TO REFERENCE BY NAME
gateway-url                     : <string>              ""              Initial URL to connect to.
gateway-credentials             : <string>              ""              HTTP credentials.
auth-scheme                     : <string               >               basic   auth scheme to use. [basic|digest|NTLM|GSS-NEGOTIATE|any]
disable-100-continue            : <true|false>          true            Disable the 100 continue feature.
method                          : <string>              ""              METHOD name to send.
timeout                         : <number>              0               Timeout waiting for response.
enable-cacert-check             : <true|false>          false           Check CA/CERT.
ssl-cert-path                   : <string>              ""              path to file.
ssl-key-path                    : <string>              ""              path to file.
ssl-key-password                : <string>              ""              password to use.
ssl-version                     : <string>              ""              ssl version
ssl-cacert-file                 : <string>              ""              CA/CERT file.
enable-ssl-verifyhost           : <true|false>          ""              Verify ssl host.
cookie-file                     : <string>              ""              Path to file to use for cookie.
enable-post-var                 : <param_name>          ""              Specify specifc param names ok to send.
bind-local                      : <string>              ""              Interface to bind to.
default-profile                 : <string>              default         Profile to use when not specified.
user-agent			: <string>		mod_httapi/1.0	User Agent header value.


<permissions>: * = default
<permission name="" value="true">

*set-params                     : <params> tag can be parsed for session params.
set-vars                        : <variables> tag can be parsed to set channel vars.
extended-data                   : Extended data is sent like full channel event data.
execute-apps                    : <execute> tag is enabled to execute apps.
expand-vars			: Allow expansion of FS ${variables}. (this opens up all FSAPI calls)
*dial                           : <dial> tag is enabled allowing outbound dialing.
dial-set-context                : <dial context=""> context attribute is permitted.
dial-set-dialplan               : <dial dialplan=""> dialplan attribute is permitted.
dial-set-cid-name               : <dial cid_name=""> cid_name attribute is permitted.
dial-set-cid-number             : <dial cid_number=""> cid_number attribute is permitted.
dial-full-originate             : <dial> full originate syntax is permitted instead of just a number.
*conference                     : <conference> tag is enabled allowing creation of conferences.
conference-set-profile          : <conference profile=""> attribure is permitted.
all                             : all permissions are set
none                            : no permissions are set


