Oracle Instant Client now supported on Apple Silicon

[jrhorn424]

The warning on the macOS installation docs can probably be removed.

The instant client is available via the custom homebrew tap, as of three hours ago.

Basic packages, tools, runtimes, and SDKs are available via Oracle.

I'm new to Oracle and this gem, and I'll be giving the installation a shot and working through some tests shortly. I figured it would be good to file an issue as an FYI, since other issues may be unblocked/resolved now.

[jhornhc]

I ran into some issues, but this might work if you have a clean environment. I needed to combine some of the knowledge present in the ruby-oci8 docs with some present in the homebrew formula docs. Basically, set the variable suggested by ruby-oci8, but use the value suggested by the formula maintainer.

Note, ARM64 builds have formulas similar to instantclient-arm64-basic, whereas Intel builds resemble instantclient-basic.

$ brew tap InstantClientTap/instantclient
$ brew install instantclient-arm64-{basic,sdk}
$ OCI_DIR=$(brew --prefix)/lib gem install ruby-oci8

Simple sanity check suggests it works:

$ ruby -r oci8 -e "p OCI8.oracle_client_version"
Warning: NLS_LANG is not set. fallback to US7ASCII.
#<OCI8::OracleVersion: 23.3.0.23.09>

It shouldn't affect ruby-oci8, but I do want to note that the binary provided by instantclient-arm64-sqlplus crashes immediately at the moment, so don't bother with it since it is indicated as optional in the gem docs.