Update v1.1.0

[eeeebbbbrrrr]

Welcome to PL/Rust v1.1.0. It is primarily a bugfix release in response to issues created and noticed immediately after v1.0.0.

New Features

Zero Copy Arrays by @eeeebbbbrrrr in #298

When a LANGUAGE plrust function has an ARRAY argument, it is now treated as a pgrx::Array, which is a zero-copy wrapper over the underlying Postgres ArrayType.

The primary change here is that v1.0.0 used a Vec<T>, so it provided random access into the array at the expense of deconstructing the whole thing ahead of time. pgrx::Array is essentially a lazy Iterator with some convenience methods like .len(). If you need random access into the array, you'll need to collect into a Vec<Option<T>> first:

CREATE OR REPLACE FUNCTION array_nth(a int[], i int) 
          RETURNS int 
          IMMUTABLE
          STRICT 
          LANGUAGE plrust AS 
$$
   let a = a.into_iter().collect::<Vec<_>>();
   Ok(a[i as usize])
$$;

SELECT array_nth(ARRAY[1,2,3,4,5,6,7,8,9,10], 5);
 array_nth 
-----------
         6

Existing functions based on PL/Rust v1.0.0 will continue to compile unchanged during a pg_dump/pg_reload cycle, but users should consider updating their function code and re-creating them with CREATE OR REPLACE FUNCTION.

Bug Fixes

Purposely fail to create on databases that aren't UTF8 by @eeeebbbbrrrr in #281

PL/Rust can only support databases that are UTF8 encoded and going forward PL/Rust will fail during CREATE EXTENSION if this is isn't the case.

It is possible in the future we can lift or greatly lessen this restriction

Incorrect type mappings by @eeeebbbbrrrr in #299

A few SQL types were incorrectly mapped to Rust types at either the argument or return type positions. The changes are:

• BYTEA is now returned as a Vec<u8>
• CSTRING is now a &CStr at the argument position and a CString at the return type position
• TID is now a pg_sys::ItemPointerData in both argument and return positions

General Project Cleanup

Add Dockerfile for quick trial use by @BradyBonnette in #287

See the documentation to quickly try PL/Rust within a Docker container!

While not at all a production-worth Dockerfile, our hope is that it'll be easy for newcomers to interactively try PL/Rust.

AnyNumeric now supports the std::iter::Sum trait pgcentralfoundation/pgrx#1117

Functions that use NUMERIC can now easily sum an array/iterator of them:

 CREATE FUNCTION sum_array(a NUMERIC[]) RETURNS NUMERIC
          IMMUTABLE 
          STRICT
          LANGUAGE PLRUST AS
$$
   Ok(Some(a.into_iter().map(|v| v.unwrap_or_default()).sum()))
$$;

SELECT sum_array(ARRAY[1, 2.0, 3.5]);
 sum_array 
-----------
       6.5

Other Minor Changes

• Make GitHub recognize the PostgreSQL license by @gurjeet in Make GitHub recognize the PostgreSQL license #292
• fix issue Compilation warning (unused variable) on v1.0.0 #279: compilation warning by @eeeebbbbrrrr in fix issue #279: compilation warning #300
• Updates to use pgrx. by @eeeebbbbrrrr in Updates to use pgrx. #294, upgrade dependencies, which includes pgrx 0.8.0 #297

Documentation

• Update create function examples to include REPLACE for easy copy/paste. by @SeanOzzy in Update create function examples to include REPLACE for easy copy/paste. #286
• Docs updates by @eeeebbbbrrrr in Docs updates #288
• README.md cleanups: by @eeeebbbbrrrr in README.md cleanups: #289
• Fixes up a few Docker documentation issues by @BradyBonnette in Fixes up a few Docker documentation issues #291

New Contributors

• @SeanOzzy made their first contribution in Update create function examples to include REPLACE for easy copy/paste. #286
• @gurjeet made their first contribution in Make GitHub recognize the PostgreSQL license #292

Full Changelog: v1.0.0...v1.1.0