From 77eedd22f7dc511f48621e6fd705e937d0e2c746 Mon Sep 17 00:00:00 2001
From: bttk <bttk@google.com>
Date: Fri, 21 Feb 2020 07:30:29 -0800
Subject: [PATCH] Running installer with option -s makes it use sudo (#20)

* Running installer with option -s makes it use sudo
* Add an example of using sudo to README
---
 README.md                         |  9 +++++++++
 installer/installer.bash.template | 16 +++++++++++-----
 2 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index 9f95705..72a418f 100644
--- a/README.md
+++ b/README.md
@@ -60,6 +60,15 @@ Think: `make install`. Someday: `bazel run install`.
     bazel run //src/path/to/pkg:install_foo -c opt ~/bin
     ```
 
+    If you need to use `sudo` to install a file in a system directory:
+
+    * **Do not** run `sudo bazel`.
+    * Instead pass flag `-s` to the installer.
+
+    ```shell
+    bazel run //src/path/to/pkg:install_foo -c opt -- -s /usr/local/bin
+    ```
+
 ## See also
 
 * [Examples](examples/README.md)
diff --git a/installer/installer.bash.template b/installer/installer.bash.template
index e07d873..4642273 100644
--- a/installer/installer.bash.template
+++ b/installer/installer.bash.template
@@ -24,6 +24,9 @@
 #
 #     If you don't want --compilation_mode=opt, run:
 #     bazel run //path/to/your:installer_target -- -g /usr/local/bin
+#
+#     To use sudo, run:
+#     bazel run //path/to/your:installer_target -- -s /usr/local/bin
 
 set -o pipefail -o errexit -o nounset
 
@@ -48,7 +51,7 @@ function error() {
 }
 
 function usage() {
-  echo >&2 "Usage: bazel run ${INSTALLER_LABEL} [-c opt] [--] [-g] [--] /INSTALL_PREFIX"
+  echo >&2 "Usage: bazel run ${INSTALLER_LABEL} [-c opt] [--] [-g] [-s] [--] /INSTALL_PREFIX"
 }
 
 # Checks that all template variables have been substituted.
@@ -78,6 +81,7 @@ function check_sources() {
 function install_file() {
   local prefix="$1"
   local i="$2"
+  local sudo="$3"
   local source="${SOURCE_FILES[${i}]}"
   local target="${TARGET_NAMES[${i}]}"
   local target_dir
@@ -92,9 +96,9 @@ function install_file() {
   fi
 
   [[ -d "${target_dir}" ]] || \
-    mkdir --parents -- "${target_dir}"
+    $sudo mkdir --parents -- "${target_dir}"
 
-  install --mode="${target_mode}" \
+  $sudo install --mode="${target_mode}" \
     -T -- "${source}" "${target_dir}/${target_name}"
 }
 
@@ -102,9 +106,11 @@ function main() {
   verify_templates
 
   local g_flag=''
-  while getopts ':gh' flag; do
+  local s_flag=''
+  while getopts ':ghs' flag; do
     case "${flag}" in
       g) g_flag='true' ;;  # Accept debug builds
+      s) s_flag='sudo' ;;  # Run with sudo
       h) usage; exit 0 ;;
       *) error "Unexpected option '-${OPTARG}'"   ;;
     esac
@@ -125,7 +131,7 @@ function main() {
   check_sources
   local i
   for ((i=0; i<${N_FILES}; i++)); do
-    install_file "${prefix}" "${i}"
+    install_file "${prefix}" "${i}" "${s_flag}"
   done
 }