Add "checkgenerate" make target to CI (#385)

download_protoc.sh

@@ -0,0 +1,35 @@
+#!/usr/bin/env bash
+
+set -e
+
+cd $(dirname $0)
+
+if [[ -z "$PROTOC_VERSION" ]]; then
+  echo "Set PROTOC_VERSION env var to indicate the version to download" >&2
+  exit 1
+fi
+PROTOC_OS="$(uname -s)"
+PROTOC_ARCH="$(uname -m)"
+case "${PROTOC_OS}" in
+  Darwin) PROTOC_OS="osx" ;;
+  Linux) PROTOC_OS="linux" ;;
+  *)
+    echo "Invalid value for uname -s: ${PROTOC_OS}" >&2
+    exit 1
+esac
+
+# This is for macs with M1 chips. Precompiled binaries for osx/amd64 are not available for download, so for that case
+# we download the x86_64 version instead. This will work as long as rosetta2 is installed.
+if [ "$PROTOC_OS" = "osx" ] && [ "$PROTOC_ARCH" = "arm64" ]; then
+  PROTOC_ARCH="x86_64"
+fi
+
+PROTOC="${PWD}/.tmp/protoc/bin/protoc"
+
+if [[ "$(${PROTOC} --version 2>/dev/null)" != "libprotoc 3.${PROTOC_VERSION}" ]]; then
+  rm -rf ./.tmp/protoc
+  mkdir -p .tmp/protoc
+  curl -L "https://github.com/google/protobuf/releases/download/v${PROTOC_VERSION}/protoc-${PROTOC_VERSION}-${PROTOC_OS}-${PROTOC_ARCH}.zip" > .tmp/protoc/protoc.zip
+  pushd ./.tmp/protoc && unzip protoc.zip && popd
+fi
+