how do I convert text to jsonB

Question

What is the proper way to convert any text (or varchar) to jsonB type in Postgres (version 9.6) ?

For example, here I am using two methods and I am getting

Answer 1

Atomic type conversion and CSV-to-JSONb

A typical parse problem in open data applications is to parse line by line a CSV (or CSV-like) text into JSONB correct (atomic) datatypes. Datatypes can be defined in SQL jargon ('int', 'text', 'float', etc.) or JSON jargon ('string', 'number'):

CREATE FUNCTION csv_to_jsonb(
  p_info text,           -- the CSV line
  coltypes_sql text[],   -- the datatype list
  rgx_sep text DEFAULT '\|'  -- CSV separator, by regular expression
) RETURNS JSONb AS $f$
  SELECT to_jsonb(a) FROM (
      SELECT array_agg(CASE
          WHEN tp IN ('int','integer','smallint','bigint') THEN to_jsonb(p::bigint)
          WHEN tp IN ('number','numeric','float','double') THEN  to_jsonb(p::numeric)
          WHEN tp='boolean' THEN to_jsonb(p::boolean)
          WHEN tp IN ('json','jsonb','object','array') THEN p::jsonb
          ELSE to_jsonb(p)
        END) a
      FROM regexp_split_to_table(p_info,rgx_sep) WITH ORDINALITY t1(p,i)
      INNER JOIN unnest(coltypes_sql) WITH ORDINALITY t2(tp,j)
      ON i=j
  ) t
$f$ language SQL immutable;

-- Example:
SELECT csv_to_jsonb(
  '123|foo bar|1.2|true|99999|{"x":123,"y":"foo"}',
  array['int','text','float','boolean','bigint','object']
);
-- results  [123,   "foo bar", 1.2,    true, 99999,  {"x": 123, "y": "foo"}]
-- that is: number, string,   number,  true, number, object