You can directly export Oracle packages as Postgres Pro packages using ora2pgpro by setting the TYPE configuration option to PACKAGE. ora2pgpro finds the package and reconstructs the abstract syntax tree (AST) representing the source code in the sources directory under the current output directory. Then it generates equivalent code in PL/pgSQL in the result directory under the current output directory. ora2pgpro aims to convert package code in such a way that the resulting package is as functional as possible and leaves WARNING messages in code places that require programmer's attention.

This is an example of an Oracle package.

CREATE OR REPLACE PACKAGE pkgc IS
TYPE r_customer_type IS RECORD(
    customer_name varchar2(50),
    credit_limit number(10,2)
);

TYPE t_customer_type IS VARRAY(2)
    OF r_customer_type;

PROCEDURE VARRAY_TEST AS
    t_customers t_customer_type := t_customer_type();
    rec r_customer_type;
    tmp_string varchar2(2000);
BEGIN
    t_customers.EXTEND;
    t_customers(t_customers.LAST).customer_name := 'ABC Corp';
    t_customers(t_customers.LAST).credit_limit  := 10000;

    FOR indx in 1 .. t_customers.COUNT LOOP
        rec := t_customers(indx);
        tmp_string := 'RECORD: ' || rec.customer_name || ', ' || rec.credit_limit;
        insert into log_table (id, line) values (1+ indx, tmp_string);
    END LOOP;
END;
BEGIN   delete from log_table;
END pkgc;

The resulting Postgres Pro package looks as follows.

CREATE SCHEMA PKGC ;

CREATE OR REPLACE FUNCTION PKGC.__INIT__() RETURNS VOID AS $$
#package

BEGIN
  delete from pkgc_log;
END;
$$ LANGUAGE plpgsql;

CREATE TYPE PKGC.r_customer_type AS (
    customer_name varchar(50),
    credit_limit numeric(10,2)
);

CREATE DOMAIN PKGC.t_customer_type PKGC.r_customer_type[];

CREATE OR REPLACE PROCEDURE PKGC.VARRAY_TEST () AS $$
#package
    DECLARE

    /*WARNING: collection constructors are not supported.*/
    t_customers PKGC.t_customer_type /*:=*/ /*t_customer_type() /*varray_constructor_call*/*/;
    rec PKGC.r_customer_type;
    tmp_string varchar(2000);
BEGIN
    t_customers = array_cat(t_customers, array_fill(NULL::PKGC.R_CUSTOMER_TYPE, ARRAY[1]));
    t_customers[array_upper(T_CUSTOMERS, 1)].customer_name = 'ABC Corp';
    t_customers[array_upper(T_CUSTOMERS, 1)].credit_limit  = 10000;

    FOR indx in 1 .. array_length(T_CUSTOMERS, 1) LOOP
        rec = t_customers[indx];
        tmp_string = 'RECORD: ' || rec.customer_name || ', ' || rec.credit_limit;
        insert into pkgc_log (id, line) values (1+ indx, tmp_string);
    END LOOP;
END; $$ LANGUAGE PLPGSQL;