REST CALL TEST

*&---------------------------------------------------------------------*
*& Report  Z_REST_CALL2
*&
*&---------------------------------------------------------------------*
*&
*&
*&---------------------------------------------------------------------*

REPORT  Z_REST_CALL2.
TYPES: BEGIN OF ts_auth
      ,   username TYPE string
      ,   password TYPE string
      ,   sid      TYPE string
      , END OF ts_auth
      .

DATA: client_init TYPE REF TO if_http_client
     , client_api  TYPE REF TO if_http_client
     , response    TYPE REF TO if_http_response
     , json        TYPE string
*     , json_doc    TYPE REF TO zcl_json_document
     , status      TYPE string
     , sid         TYPE string
     , server      TYPE string
     , auth        TYPE ts_auth
     , txt TYPE string.

types: begin of ty_hash,
             ContractNumber type string,
             b type i,
             c type i,
          end of ty_hash,
          ty_hash_tab type standard table of ty_hash.
     data: ls_deep type ty_hash,
           ls_exp  type ty_hash,
           lt_deep type ty_hash_tab,
           lt_exp  type stringtab.
FIELD-SYMBOLS: <F1>, <F2>, <F3>.

cl_http_client=>create_by_url(
   EXPORTING url = 'http://www.your-site.com/api/contract'
   IMPORTING client = client_init
   ).

client_init->send( ).
client_init->receive( ).

json = client_init->response->get_cdata( ).
client_init->close( ).



*WRITE:/ json.

perform json_to_data using
              '{"ContractNumber":"123444","b":2,"c":3}'
            changing ls_exp.

ASSIGN ls_exp to <F1>.
DO 1 TIMES.
  ASSIGN COMPONENT SY-INDEX OF STRUCTURE <F1> TO <F3>.
  WRITE <F3>.
ENDDO.
*&---------------------------------------------------------------------*
*&      Form  json_to_data
*&---------------------------------------------------------------------*
form json_to_data using json type string changing data type any.
  data: lv_off type i.
  data: lv_len type i.
  data: lv_key type string.
  data: lv_value type string.
  data: lv_char type char1.    "Current chacater
  data: lv_pchar type char1.   "Previous character
  data: lv_instr type boole_d. "Indicator: cursor in string
  data: lv_level type i.       "Depth inside a block
  data: lv_table type boole_d.
  field-symbols: <fk> type string.
  field-symbols: <data> type any.
  field-symbols: <table> type any table.
  field-symbols: <sotab> type sorted table.
  field-symbols: <sttab> type standard table.
  field-symbols: <line> type any.
  data: ls_line type ref to data.
  data: lr_td type ref to cl_abap_typedescr.
  data: lr_ttd type ref to cl_abap_tabledescr.

* If the incoming json contains no '{}[]', we are dealing with
* a basic (scalar) value that is simply assigned to the data
* and then we return
  if json na '{}[]'.
* Replace escape characters (TODO: Check if there are more!)
    lv_value = json.
    replace all occurrences of '\n' in lv_value with cl_abap_char_utilities=>newline.
    replace all occurrences of '\t' in lv_value with cl_abap_char_utilities=>horizontal_tab.
    replace all occurrences of '\f' in lv_value with cl_abap_char_utilities=>form_feed.
    replace all occurrences of '\v' in lv_value with cl_abap_char_utilities=>vertical_tab.
    replace all occurrences of '\b' in lv_value with cl_abap_char_utilities=>backspace.
    replace all occurrences of '\\' in lv_value with '\'.
* TODO: Deal with specific data types, e.g. dates etc.
    data = lv_value.
    exit.
  endif.

  lv_len = strlen( json ).

* Check if we are dealing with a table
  lr_td = cl_abap_typedescr=>describe_by_data( data ).
  if lr_td->type_kind = cl_abap_typedescr=>typekind_table.
* This information is used later...
    lv_table = 'X'.
    assign data to <table>.
    create data ls_line like line of <table>.
    assign ls_line->* to <line>.
  else.
    lv_table = ' '.
  endif.

* Reset counters/flags
  lv_off = 0.
  lv_instr = ' '.
  lv_level = 0.
  assign lv_key to <fk>.

  while lv_off < lv_len.
    lv_char = json+lv_off(1).

**********************************************************************
* IN STRING
**********************************************************************
* Character is in a string delimited by double quotes
    if lv_instr = 'X'.
      if lv_char = '"'.
* Switch out of delimited character string
        if lv_pchar ne '\'.
          lv_instr = ' '.
        else.
          concatenate <fk> lv_char into <fk> respecting blanks.
        endif.
      else.
        concatenate <fk> lv_char into <fk> respecting blanks.
      endif.

**********************************************************************
* OUTSIDE STRING
**********************************************************************
* Character is not in a string delimited by double quotes
    else.

* On opening character, shift level up
      if lv_char ca '{['.
        add 1 to lv_level.
      endif.

* When the value is contained in a {}/[], the entire value must
* be passed to the next level of processing
      if lv_level > 1.
        concatenate <fk> lv_char into <fk> respecting blanks.
      else.
        if lv_char ca '[{'. "<- Chars ignored outside of str
        elseif lv_char = ':'.
          assign lv_value to <fk>.
* The key collected up to now is assigned to the data member
          translate lv_key to upper case.
          shift lv_key left deleting leading space.
          assign component lv_key of structure data to <data>.

* End of a key/value pair (we bump up against delimiter) - pass to next level
        elseif ( lv_char = ',' or lv_char = '}' ) and lv_table = space.

* Process collected value
          shift lv_value left deleting leading space.
          perform json_to_data using lv_value changing <data>.

* Clear key and value
          clear: lv_key, lv_value.

          assign lv_key to <fk>.

          clear: lv_key, lv_value.

* End of a key/value pair (we bump up against delimiter) - pass to next level
* But in table mode, we pass an instance of a row of the table, and afterward
* add it to the table
        elseif ( lv_char = ',' or lv_char = ']' ) and lv_table = 'X'.

* Process collected value
* Inside array in JSON, there are no keys, only list of values, the collected
* value is in lv_key
          shift lv_key left deleting leading space.
          perform json_to_data using lv_key changing <line>.

* On return: if dealing with table, add the record to the table
          lr_ttd ?= lr_td.
          if lr_ttd->table_kind = cl_abap_tabledescr=>tablekind_sorted
            or lr_ttd->table_kind = cl_abap_tabledescr=>tablekind_hashed.
            assign data to <sotab>.
            insert <line> into table <sotab>.
          else.
            assign data to <sttab>.
            append <line> to <sttab>.
          endif.
          clear <line>.

* Clear key and value
          clear: lv_key, lv_value.

          assign lv_key to <fk>.

          clear: lv_key, lv_value.

* Switch cursor into delimited string; consecutive characters
* are then treated as part of a key or value, even if they are
* special characters
        elseif lv_char = '"'.
          lv_instr = 'X'.

* Other chars processed as either key or value
        else.
          concatenate <fk> lv_char into <fk> respecting blanks.
        endif.

      endif.

* On closing character, shift level down again
      if lv_char ca '}]'.
        subtract 1 from lv_level.
      endif.

* END: Are we in string or out?
    endif.

    lv_pchar = lv_char.
    add 1 to lv_off.
  endwhile.
endform.                    "json_to_data