From 2896370880ea67a940c09e4c8fca2d5f71aa8ac5 Mon Sep 17 00:00:00 2001
From: Jean-Paul Calderone <exarkun@twistedmatrix.com>
Date: Thu, 4 Apr 2019 12:50:05 -0400
Subject: [PATCH] Factor some complexity out of the Dockerfile for easier reuse

---
 .circleci/Dockerfile.debian-8 |  5 +----
 .circleci/prepare-image.sh    | 24 ++++++++++++++++++++++++
 2 files changed, 25 insertions(+), 4 deletions(-)
 create mode 100755 .circleci/prepare-image.sh

diff --git a/.circleci/Dockerfile.debian-8 b/.circleci/Dockerfile.debian-8
index 11e6e93ec..ae6845d73 100644
--- a/.circleci/Dockerfile.debian-8
+++ b/.circleci/Dockerfile.debian-8
@@ -21,7 +21,4 @@ RUN apt-get --quiet update && \
 # cache friendly but there's no Docker layer cache on CircleCI anyway!
 COPY . ${BUILD_SRC_ROOT}
 
-RUN usermod --home /tmp/nobody nobody
-RUN chown --recursive nobody:nogroup "${BUILD_SRC_ROOT}"
-RUN sudo --set-home -u nobody "${BUILD_SRC_ROOT}"/.circleci/create-virtualenv.sh "${WHEELHOUSE_PATH}" "${VIRTUALENV_PATH}"
-RUN sudo --set-home -u nobody "${BUILD_SRC_ROOT}"/.circleci/populate-wheelhouse.sh "${WHEELHOUSE_PATH}" "${VIRTUALENV_PATH}" "${BUILD_SRC_ROOT}"
+RUN "${BUILD_SRC_ROOT}"/.circleci/prepare-image.sh "${WHEELHOUSE_PATH}" "${VIRTUALENV_PATH}" "${BUILD_SRC_ROOT}"
diff --git a/.circleci/prepare-image.sh b/.circleci/prepare-image.sh
new file mode 100755
index 000000000..6b85b251a
--- /dev/null
+++ b/.circleci/prepare-image.sh
@@ -0,0 +1,24 @@
+#!/bin/bash
+
+# https://vaneyckt.io/posts/safer_bash_scripts_with_set_euxo_pipefail/
+set -euxo pipefail
+
+# The filesystem location of the wheelhouse which we'll populate with wheels
+# for all of our dependencies.
+WHEELHOUSE_PATH="$1"
+shift
+
+# The filesystem location of the root of a virtualenv we can use to get/build
+# wheels.
+BOOTSTRAP_VENV="$1"
+shift
+
+# The filesystem location of the root of the project source.  We need this to
+# know what wheels to get/build, of course.
+PROJECT_ROOT="$1"
+shift
+
+usermod --home /tmp/nobody nobody
+chown --recursive nobody:nogroup "${PROJECT_ROOT}"
+sudo --set-home -u nobody "${PROJECT_ROOT}"/.circleci/create-virtualenv.sh "${WHEELHOUSE_PATH}" "${BOOTSTRAP_VENV}"
+sudo --set-home -u nobody "${PROJECT_ROOT}"/.circleci/populate-wheelhouse.sh "${WHEELHOUSE_PATH}" "${BOOTSTRAP_VENV}" "${PROJECT_ROOT}"