Initial Commit

utils/track_posts.sh

@@ -0,0 +1,80 @@
+#!/bin/sh
+
+# This is meant to track the contents of /public/blog/*.md
+# to maintain an up-to-date list of blog posts.
+#
+# It outputs JSON to stdout:
+# Given a file /public/blog/2019-01-01-foo-bar.md of contents:
+#
+# ---
+# title: Foo Bar
+# date: 2019-01-01
+# arbitrary_key: arbitrary_value
+# ---
+# # Foo Bar
+#
+# it will output:
+# {
+#     posts: [
+#         {
+#           id: "2019-01-01-foo-bar",
+#           title: "Foo Bar",
+#           date: "2019-01-01",
+#           arbitrary_key: "arbitrary_value",
+#           url: "/blog/2019-01-01-foo-bar"
+#         }
+#     ]
+# }
+
+# It should also read the YAML Front Matter of each post
+# and place all the keys in the JSON output.
+
+# The script should be run from the root of the project.
+
+# SCRIPT ENTRY
+echo "{"
+echo "  \"posts\": ["
+
+# Front-Matter Extraction (procedure)
+# Given data, extract the YAML Front Matter header
+# and output it as JSON.
+extract_front_matter() {
+    local data="$1"
+    local front_matter=$(echo "$data" | sed -n '/^---/,/^---/p')
+    echo "$front_matter" | sed '1d;$d' | sed 's/^/    "/' | sed 's/: /": "/' | sed 's/$/"/' | tr '\n' ',' | sed 's/,$//' | sed 's/"tags": "\[\(.*\)\]"/"tags": \[\1\]/g' | sed "s/'/\"/g"
+}
+
+# Find files via Regex
+# Find all files in /public/blog/*.md
+# Process and extract the front matter of each file.
+# Output the JSON representation of the front matter.
+extract_files() {
+    local files=$(find public/blog -type f -name "*.md")
+    for file in $files; do
+        # Enter, create {} for each file
+        echo "    {"
+
+        echo "      \"metadata\": {"
+
+        local data=$(cat $file)
+        local front_matter=$(extract_front_matter "$data")
+        echo "$front_matter"
+
+        echo "      },"
+
+        # Add the id and url
+        local id=$(echo "$file" | sed 's/public\/blog\///' | sed 's/\.md//')
+        echo "      \"id\": \"$id\","
+        echo "      \"url\": \"/blog/$id.md\""
+
+        # Exit, close {} for each file 
+        echo "    },"
+    done
+}
+
+# Process all files
+extract_files | sed '$s/,$//'
+
+# SCRIPT EXIT
+echo "  ]"
+echo "}"