mydoghasworms · April 2, 2012 09:26 · SP513582 · Feb 21, 2014
diff --git a/json2data.abap b/json2data.abap
 *&---------------------------------------------------------------------*
 *&      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
	&---------------------------------------------------------------------
	*& 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