Download Rustup files from CDN

Author: jdno

local/rustup.sh

@@ -6,3 +6,51 @@
 
 set -euo pipefail
 IFS=$'\n\t'
+
+RUSTUP_REPO="https://github.com/rust-lang/rustup"
+RUSTUP_DEFAULT_BRANCH="master"
+
+# S3 bucket from which to download the Rustup artifacts
+S3_BUCKET="rustup-builds"
+
+# CDN from which to download the CI artifacts
+DOWNLOAD_BASE="https://rustup-builds.rust-lang.org"
+
+# The artifacts for the following targets will be downloaded and copied during
+# the release process. At least one target is required.
+DOWNLOAD_TARGETS=(
+    "x86_64-unknown-linux-gnu"
+)
+
+# The following files will be downloaded and put into the local MinIO instance.
+DOWNLOAD_FILES=(
+    "rustup-init"
+    "rustup-init.sha256"
+    "rustup-setup"
+    "rustup-setup.sha256"
+)
+
+channel="$1"
+override_commit="$2"
+
+if [[ "${override_commit}" = "" ]]; then
+    echo "==> detecting the last Rustup commit on the default branch"
+    commit="$(git ls-remote "${RUSTUP_REPO}" | grep "refs/heads/${RUSTUP_DEFAULT_BRANCH}" | awk '{print($1)}')"
+else
+    echo "=>> using overridden commit ${override_commit}"
+    commit="${override_commit}"
+fi
+
+for target in "${DOWNLOAD_TARGETS[@]}"; do
+    if ! mc stat "local/artifacts/builds/${commit}/dist/${target}" >/dev/null 2>&1; then
+        echo "==> copying ${target} from S3"
+
+        for file in "${DOWNLOAD_FILES[@]}"; do
+            if curl -Lo /tmp/component "${DOWNLOAD_BASE}/${commit}/dist/${target}/${file}" --fail; then
+                mc cp /tmp/component "local/artifacts/builds/${commit}/dist/${target}/${file}" >/dev/null
+            fi
+        done
+    else
+        echo "==> reusing cached ${target} target"
+    fi
+done