envoy: refactor envoy embedding (#2296)

* envoy: add full version

* remove unused import

* envoy: refactor envoy embedding

* fix lint

* commit ignored files

* maybe fix test

scripts/get-envoy.bash

@@ -6,7 +6,7 @@ export PATH
 
 _project_root="$(cd "$(dirname "${BASH_SOURCE[0]}")" >/dev/null 2>&1 && pwd)/.."
 _envoy_version=1.17.3
-_dir="${DIR:-"$_project_root/bin"}"
+_dir="$_project_root/internal/envoy/files"
 _target="${TARGET:-"$(go env GOOS)-$(go env GOARCH)"}"
 
 # until m1 macs are supported, fallback to x86 and use rosetta
@@ -16,31 +16,20 @@ fi
 
 _url="https://github.com/pomerium/envoy-binaries/releases/download/v${_envoy_version}/envoy-${_target}"
 
-# create the directory if it doesn't exist
-mkdir -p "$_dir"
-
-# download the shasum of the binary
 curl \
   --compressed \
   --silent \
   --location \
+  --time-cond "$_dir/envoy-$_target" \
+  --output "$_dir/envoy-$_target" \
+  "$_url"
+
+curl \
+  --compressed \
+  --silent \
+  --location \
+  --time-cond "$_dir/envoy-$_target.sha256" \
   --output "$_dir/envoy-$_target.sha256" \
   "$_url.sha256"
 
-# if the shasum doesn't match (or the binary doesn't exist), re-download
-if ! (cd "$_dir" && shasum -c "envoy-$_target.sha256" >/dev/null 2>&1) ; then
-  curl \
-    --compressed \
-    --silent \
-    --location \
-    --output "$_dir/envoy-$_target" \
-    "$_url"
-fi
-
-# save the bare name
-cp -f "$_dir/envoy-$_target" "$_dir/envoy"
-cp -f "$_dir/envoy-$_target.sha256" "$_dir/envoy.sha256"
-
-# save to the embedded files in the envoy package
-cp -f "$_dir/envoy-$_target.sha256" "$_project_root/internal/envoy/files/envoy.sha256"
-echo "$_envoy_version" > "$_project_root/internal/envoy/files/envoy.version"
+echo "$_envoy_version" > "$_dir/envoy-$_target.version"