This API is used to Get Problem list
Please check example usage of Vision Helpdesk API

Operation : view_problems
Module : problem

$postfields["vis_module"] = "problem";
// This is the module under which you wish to perform operation

$postfields["vis_operation"] = "view_problems";
// This is the operation field

Similarly you can fetch problem using filter criteria:

$postfields["vis_module"] = "problem";
// This is the module under which you wish to perform operation

$postfields["vis_operation"] = "view_problems";
// This is the operation field

[Optional]

$postfields["vis_filter_id"] = 1;

$postfields["criteria"] = "test";

Below is example API URL to get list of problem

XML:
http://visiononlinedemo.com/support/api/index.php?
vis_txtusername=admin
&vis_txtuserpass=21232f297a57a5a743894a0e4a801fc3
&vis_module=problem
&vis_operation=view_problems

JSON:
http://visiononlinedemo.com/support/api/index.php?
vis_txtusername=admin
&vis_txtuserpass=21232f297a57a5a743894a0e4a801fc3
&vis_module=problem
&vis_operation=view_problems
&vis_encode=json

OR use "access token" to get list of problem

XML:
http://visiononlinedemo.com/support/api/index.php?
vis_txttoken=WXprMk1UY3dZV1V6WWpZeU16RmpOelF3TVdReE5UWTJOVGMyTm1VeU4yUT0=
&vis_module=problem
&vis_operation=view_problems

JSON:
http://visiononlinedemo.com/support/api/index.php?
vis_txttoken=WXprMk1UY3dZV1V6WWpZeU16RmpOelF3TVdReE5UWTJOVGMyTm1VeU4yUT0=
&vis_module=problem
&vis_operation=view_problems
&vis_encode=json

Below is example API URL to get list of problem using filter criteria

XML:
http://visiononlinedemo.com/support/api/index.php?
vis_txtusername=admin
&vis_txtuserpass=21232f297a57a5a743894a0e4a801fc3
&vis_module=problem
&vis_operation=view_problems
&vis_filter_id=1
&criteria=test

JSON:
http://visiononlinedemo.com/support/api/index.php?
vis_txtusername=admin
&vis_txtuserpass=21232f297a57a5a743894a0e4a801fc3
&vis_module=problem
&vis_operation=view_problems
&vis_filter_id=1
&criteria=test
&vis_encode=json

OR use "access token" to get list of problem using filter criteria

XML:
http://visiononlinedemo.com/support/api/index.php?
vis_txttoken=WXprMk1UY3dZV1V6WWpZeU16RmpOelF3TVdReE5UWTJOVGMyTm1VeU4yUT0=
&vis_module=problem
&vis_operation=view_problems
&vis_filter_id=1
&criteria=test

JSON:
http://visiononlinedemo.com/support/api/index.php?
vis_txttoken=WXprMk1UY3dZV1V6WWpZeU16RmpOelF3TVdReE5UWTJOVGMyTm1VeU4yUT0=
&vis_module=problem
&vis_operation=view_problems
&vis_filter_id=1
&criteria=test
&vis_encode=json