Merge pull request #99 from github/kpaulisse-git-submodule-example

Add example git submodule script

Author: kpaulisse

examples/script-overrides/git-extract-submodules/README.md

@@ -0,0 +1,3 @@
+# git submodules
+
+See https://github.com/github/octocatalog-diff/issues/88 for context.

examples/script-overrides/git-extract-submodules/git-extract.sh

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+#!/bin/bash
+
+# This script is called from lib/octocatalog-diff/catalog-util/git.rb and is used to
+# archive and extract a certain branch of a git repository into a target directory.
+
+if [ -z "$OCD_GIT_EXTRACT_BRANCH" ]; then
+  echo "Error: Must declare OCD_GIT_EXTRACT_BRANCH"
+  exit 255
+fi
+
+if [ -z "$OCD_GIT_EXTRACT_TARGET" ]; then
+  echo "Error: Must declare OCD_GIT_EXTRACT_TARGET"
+  exit 255
+fi
+
+set -euf -o pipefail
+git clone --single-branch -b "$OCD_GIT_EXTRACT_BRANCH" . "$OCD_GIT_EXTRACT_TARGET"
+( cd "$OCD_GIT_EXTRACT_TARGET" && git submodule init && git submodule sync  && git submodule update )