PL/JSON Tweaks

You can tweak the behavior of PL/JSON by setting various variables in the packages. The following sections are a description of the possible adjustments you can do.

pljson_printer

In the printer package you can edit the line break method to Linux, Windows or macOS style. You can also change the indentation to the tabular char, or change the number of spaces.

pljson_parser

The parser is extended to accept more than just pure JSON. The variable json_strict is defaulted to false and can be set to true to force PL/JSON to only accept proper JSON. The current implementation allows input to contain comments with the /* */ notation. Furthermore it extends the definition of a string to allow single quotes and converts names into strings. The grammar for names accepted by PL/JSON is:

name     : (letter) ((letter| digits | us)*);

However, the values true, false and null will not be handled as names.

Example of usage with the extended grammar:

{
  abc : '123"'
}

Parsed and emitted:

{
  "abc" : "123\""
}

pljson_parser functions

Even though javascript functions are not a part of JSON, you might want to emit functions if your receiving client is a browser. This is how you do it:

declare
  obj pljson := pljson();
begin
  obj.put('test', pljson_value('function() {return 1;}', esc => false ));
  obj.print;
end;

The output is:

{
  "test": /**/function() {return 1;}/**/
}

Which is not valid JSON but will work in javascript. The surrounding /**/ is a message to the parser to start and stop building a unescaped pljson_value string:

declare
  obj pljson := pljson('{"test": /**/function() {return 1;}/**/}');
begin
  obj.print;
end;

-- {
--   "test": /**/function() {return 1;}/**/
-- }