Transforms for jsonb to PL/Python

Add a new contrib module jsonb_plpython that provide a transform between
jsonb and PL/Python.  jsonb values are converted to appropriate Python
types such as dicts and lists, and vice versa.

Author: Anthony Bykov <a.bykov@postgrespro.ru>
Reviewed-by: Aleksander Alekseev <a.alekseev@postgrespro.ru>
Reviewed-by: Nikita Glukhov <n.gluhov@postgrespro.ru>

1 files changed, 19 insertions, 0 deletions

diff --git a/contrib/jsonb_plpython/jsonb_plpythonu--1.0.sql b/contrib/jsonb_plpython/jsonb_plpythonu--1.0.sql
new file mode 100644
index 00000000000..3fa89885a63
--- /dev/null
+++ b/contrib/jsonb_plpython/jsonb_plpythonu--1.0.sql
@@ -0,0 +1,19 @@
+/* contrib/jsonb_plpython/jsonb_plpythonu--1.0.sql */
+
+-- complain if script is sourced in psql, rather than via CREATE EXTENSION
+\echo Use "CREATE EXTENSION jsonb_plpythonu" to load this file. \quit
+
+CREATE FUNCTION jsonb_to_plpython(val internal) RETURNS internal
+LANGUAGE C STRICT IMMUTABLE
+AS 'MODULE_PATHNAME';
+
+CREATE FUNCTION plpython_to_jsonb(val internal) RETURNS jsonb
+LANGUAGE C STRICT IMMUTABLE
+AS 'MODULE_PATHNAME';
+
+CREATE TRANSFORM FOR jsonb LANGUAGE plpythonu (
+    FROM SQL WITH FUNCTION jsonb_to_plpython(internal),
+    TO SQL WITH FUNCTION plpython_to_jsonb(internal)
+);
+
+COMMENT ON TRANSFORM FOR jsonb LANGUAGE plpythonu IS 'transform between jsonb and Python';