an in-progress buggy RSS feed generator

config.conf

blog_name="My blog"
blog_link=https://website.com/blog
blog_description="My blog description"
blog_feed=rss.xml
blog_dir=site
blog_posts=posts

makerss.sh

#!/bin/bash

function set_paths {
  # change if you have a different config file
  CONFIG_PATH=config.conf
}

function source_config {
  # set feed_name to blog_feed value in config
  feed_name=$(grep -oP '(?<=blog_feed=).*' $CONFIG_PATH)

  touch $feed_name

  # set posts folder to value in config
  POSTS_PATH=$(grep -oP '(?<=blog_posts=).*' $CONFIG_PATH)

  # make posts folder if it doesn't exist
  mkdir -p $POSTS_PATH

  # set site destination folder
  site_folder=$(grep -oP '(?<=blog_dir=).*' $CONFIG_PATH)

  # make site folder if doesn't exist
  mkdir -p $site_folder
}

function check_valid {
  # source config file
  if [ ! -e $CONFIG_PATH ]; then
    echo "$CONFIG_PATH not found"
    exit 1
  fi

  # Source the config file
  . $CONFIG_PATH

  if [[ -z $blog_name || -z $blog_link || -z $blog_description || -z $blog_feed || -z $blog_dir || -z $blog_posts ]]; then
    echo "$CONFIG_PATH missing arguments."
    exit 1
  fi
}

function create_feed {
  # feed meta
  > $feed_name #erases file, start from scratch
  echo '<rss version="2.0">'>> $feed_name
  echo "<channel>" >> $feed_name
  echo "<title>$blog_name</title>" >> $feed_name
  echo "<link>$blog_link</link>" >> $feed_name
  echo "<description>$blog_description</description>" >> $feed_name

  # individual feed items
  for file in $POSTS_PATH/*.md
  do
    echo "<item>" >> $feed_name
    # get individual title
    echo "<title>" >> $feed_name
    grep -oP '(?<=title: ).*' $file >> $feed_name
    echo "</title>" >> $feed_name

    # get individual url
    echo "<link>" >> $feed_name
    echo $blog_link/${file// /-} >> $feed_name
    echo "</link>" >> $feed_name

    # echo formatted pubdate
    echo "<pubDate>" >> $feed_name
    # thanks to https://lynxbee.com/create-pubdate-tag-in-rss-xml-using-linux-date-command/#.ZA9akY7MJhF
    pubDate=$(grep -oP '(?<=date: ).*' $file)
    date -d "$pubDate" +"%a, %d %b %Y %H:%M:%S %z" >> $feed_name
    echo "</pubDate>" >> $feed_name

    # echo description of each item
    echo "<description>" >> $feed_name
    ## wrap html content in a CDATA for rss 2.0 spec
    echo "<![CDATA[" >> $feed_name
    pandoc --to=html5 -o - $file | cat >> $feed_name
    echo "]]>" >> $feed_name
    echo "</description>" >> $feed_name

    echo "</item>" >> $feed_name
  done

  echo -e '</channel>
  </rss>' >> $feed_name
}

set_paths
check_valid
source_config
create_feed