Make rapids-get-artifact work locally (#59)

This PR ensures that `rapids-get-artifact` works locally.

This request was made by @bdice who was attempting to use the script
locally to debug some CUDA 12 issues.

I've moved the logic for downloading, extracting, and printing the
artifact's path to a new script, `_rapids-download-from-s3`.

This script is then called by both `rapids-download-from-s3` and
`rapids-get-artifact`.

In the future, I would like to rework some of the scripts regarding
artifact uploading/downloading, but I think we need to finish reworking
the wheel workflows before that will be feasible.

tools/_rapids-download-from-s3

@@ -0,0 +1,27 @@
+#!/bin/bash
+# A utility script that downloads an artifact archive from S3, untars it,
+# and prints the location where it was untarred.
+# The script can be used locally and in CI.
+# Positional Arguments:
+#   1) path to s3 artifact
+#   2) location to untar it to
+set -euo pipefail
+source rapids-constants
+
+s3_dl_path="$1"
+untar_dest="$2"
+
+mkdir -p "${untar_dest}"
+
+if [ "${CI:-false}" = "false" ]; then
+  # shellcheck disable=SC2001
+  s3_dl_path=$(echo "${s3_dl_path}" | sed "s|s3://${RAPIDS_DOWNLOADS_BUCKET}|https://${RAPIDS_DOWNLOADS_DOMAIN}|")
+  rapids-echo-stderr "Downloading and decompressing ${s3_dl_path} into ${untar_dest}"
+  wget -qO- "${s3_dl_path}" | tar xzf - -C "${untar_dest}"
+else
+  rapids-echo-stderr "Downloading and decompressing ${s3_dl_path} into ${untar_dest}"
+  aws s3 cp --only-show-errors "${s3_dl_path}" - | tar xzf - -C "${untar_dest}"
+fi
+
+# echo path to untarred contents
+echo -n "${untar_dest}"

tools/rapids-download-from-s3

@@ -5,7 +5,6 @@
 #   1) package name to generate s3 path for
 #   2) location to untar it to
 set -euo pipefail
-source rapids-constants
 export RAPIDS_SCRIPT_NAME="rapids-download-from-s3"
 
 if [ -z "$1" ] || [ -z "$2" ]; then
@@ -14,20 +13,6 @@ if [ -z "$1" ] || [ -z "$2" ]; then
 fi
 
 s3_dl_path="$(rapids-s3-path)$1"
-
 untar_dest="$2"
-mkdir -p "${untar_dest}"
-
-if [ "${CI:-false}" = "false" ]; then
-  # shellcheck disable=SC2001
-  s3_dl_path=$(echo "${s3_dl_path}" | sed "s|s3://${RAPIDS_DOWNLOADS_BUCKET}|https://${RAPIDS_DOWNLOADS_DOMAIN}|")
-  rapids-echo-stderr "Downloading and decompressing ${s3_dl_path} into ${untar_dest}"
-  wget -qO- "${s3_dl_path}" | tar xzf - -C "${untar_dest}"
-else
-  rapids-echo-stderr "Downloading and decompressing ${s3_dl_path} into ${untar_dest}"
-  aws s3 cp --only-show-errors "${s3_dl_path}" - | tar xzf - -C "${untar_dest}"
-fi
-
 
-# echo path to untarred contents
-echo -n "${untar_dest}"
+_rapids-download-from-s3 "$s3_dl_path" "$untar_dest"

tools/rapids-get-artifact

@@ -8,10 +8,7 @@
 set -euo pipefail
 source rapids-constants
 
-artifact_path="s3://${RAPIDS_DOWNLOADS_BUCKET}/${1}"
+s3_dl_path="s3://${RAPIDS_DOWNLOADS_BUCKET}/${1}"
 untar_dest=$(mktemp -d)
 
-rapids-echo-stderr "Downloading and decompressing ${artifact_path} into ${untar_dest}"
-aws s3 cp --only-show-errors "${artifact_path}" - | tar xzf - -C "${untar_dest}"
-
-echo -n "${untar_dest}"
+_rapids-download-from-s3 "$s3_dl_path" "$untar_dest"