install-protoc

#! /usr/bin/env bash
# Unconditionally install the exact version of protoc that we use,
# overwriting whatever is installed in /usr/local/bin.
#
# We have a CI job that checks the generated code, looking for an exact match,
# so it's important that everyone use the same version of protoc.

# Unofficial bash strict mode
set -euo pipefail
IFS=$'\n\t'

# Don't use sudo if we're root. Not every Docker image has sudo.
SUDO=sudo
if [[ $EUID == "0" ]]; then
    SUDO=
fi

if ! type -P unzip >/dev/null; then
    echo "Installing unzip..."
    # This should only happen on Linux. MacOS ships with unzip.
    sudo apt-get install -y unzip
fi

echo "Installing protoc..."

# Download protoc
protoc_version="3.17.0"
protoc_os="osx-x86_64"
if [[ $OSTYPE == linux* ]]; then
    protoc_os="linux-x86_64"
fi
mkdir _tools
cd _tools
protoc_zip="protoc-$protoc_version-$protoc_os.zip"
curl -OL "https://github.com/protocolbuffers/protobuf/releases/download/v$protoc_version/$protoc_zip"

# Install protoc to /usr/local
prefix=/usr/local
unzip -o $protoc_zip -d tmp
$SUDO mkdir -p $prefix/bin
$SUDO mv tmp/bin/protoc $prefix/bin/protoc
$SUDO mkdir -p $prefix/include/google/protobuf
$SUDO rm -rf $prefix/include/google/protobuf
$SUDO mv tmp/include/google/protobuf $prefix/include/google/protobuf
cd ..
rm -rf _tools