example determining user from service now

get_caller_id.abap

  method get_caller_id.

    data: uri             type        string
        , body            type        string
        , token              type        string
        , agreements         type        string
        , lo_response    type ref to     if_rest_entity
*             , parser TYPE REF TO /ui5/cl_json_parser
        , user type ref to data
        , user_row type ref to data
        .

*format of the uri see service now api documentation

*    * create a http client
    me->create_client( ).


    uri = |/sys_user?sysparm_limit=1&user_name={ i_email }|.

* Set the URI if any
    cl_http_utility=>set_request_uri(
      exporting
        request = me->http_client->request    " HTTP Framework (iHTTP) HTTP Request
        uri     = uri                     " URI String (in the Form of /path?query-string)
    ).


* Set request header if any
    call method me->rest_client->if_rest_client~set_request_header
      exporting
        iv_name  = 'accept'
        iv_value = 'application/json'.

    call method me->rest_client->if_rest_client~set_request_header
      exporting
        iv_name  = 'content-type'
        iv_value = 'application/json'.

* HTTP GET
    me->rest_client->if_rest_client~get( ).

* HTTP response
    lo_response = me->rest_client->if_rest_client~get_response_entity( ).

* HTTP return status
    data(http_status)   = lo_response->get_header_field( '~status_code' ).

* HTTP JSON return string
    data(json_response) = lo_response->get_string_data( ).

* parse json and find caller id
* /ui5/cl_json_parser

*      lr_data TYPE REF TO data,
*      lv_val  TYPE string.


    user = /ui2/cl_json=>generate( json = json_response ).
*    LOOP AT User->result ASSIGNING FIELD-SYMBOL(<user_row>).
*
*      /ui2/cl_data_access=>create( ir_data = <User_row> iv_component = `sys_id`)->value( IMPORTING ev_data = r_caller_id ).
*    ENDLOOP.


    field-symbols: <data>   type data
                 , <result> type data
                 .

*data : ref type any.
*
*ref = /ui2/cl_data_access=>create( ir_data = user iv_component = `RESULT`)->ref( ).

* reference for the dynamic access to the json response
* https://wiki.scn.sap.com/wiki/display/Snippets/Dynamic+Data+Accessor+Helper+Class+for+ABAP

    data(ref) = /ui2/cl_data_access=>create( iv_data = user iv_component = `RESULT[1]`)->ref( ) ."at(`SYS_ID`)->ref( ) .

    if ref is bound.
      assign ref->* to <data>.
      assign component `SYS_ID` of structure <data> to <result>.
    endif.

    data: type_converter type char50
        .
    FIELD-SYMBOLS: <field> type any
                   .

*    get REFERENCE OF <result> into <field>.
    ASSIGN <result>->* to <field>.

    if <field> is assigned.
*      type_converter = <result>.
      r_caller_id  = <field>.
    endif.


  endmethod.