Add Ebook generation script (#207)

generate-epub.sh

@@ -0,0 +1,40 @@
+#! /usr/bin/env sh
+
+generate_from_stdin() {
+  outfile=$1
+  language=$2
+
+  echo "Generating '$language' ..."
+
+  pandoc --metadata-file=epub-metadata.yaml --metadata=lang:$2 --from=markdown -o $1 <&0
+
+  echo "Done! You can find the '$language' book at ./$outfile"
+}
+
+generate_with_solutions () {
+  tmpfile=$(mktemp /tmp/sytem-design-primer-epub-generator.XXX)
+
+  cat ./README.md >> $tmpfile
+
+  for dir in ./solutions/system_design/*; do 
+    case $dir in *template*) continue;; esac
+    case $dir in *__init__.py*) continue;; esac
+    : [[ -d "$dir" ]] && ( cd "$dir" && cat ./README.md >> $tmpfile && echo "" >> $tmpfile )
+  done
+
+  cat $tmpfile | generate_from_stdin 'README.epub' 'en'
+
+  rm "$tmpfile"
+}
+
+generate () {
+  name=$1
+  language=$2
+
+  cat $name.md | generate_from_stdin $name.epub $language
+}
+
+generate_with_solutions
+generate README-ja ja
+generate README-zh-Hans zh-Hans
+generate README-zh-TW zh-TW