A shell script to make placeholder images for those linked in Instruqt assignment.md files

mpi.sh

#!/bin/bash

# Requires imagemagick. `brew install imagemagick`

# Make Placeholder Images (MPI)

find . -type f -name "assignment.md" | while read md_file; do
  # Extract the directory where the current markdown file is located
  dir=$(dirname "$md_file")
  
  # Parse the markdown file for image links
  grep '!\[.*\](.*)' "$md_file" | while read -r img_link; do
    # Extract the image file path from the markdown image link
    img_path=$(echo "$img_link" | sed -n 's/.*](\([^)]*\)).*/\1/p')

    # Form the full path of the image in the ../assets/ directory
    img_filename=$(basename "$img_path")
    img_full_path="$dir/../assets/$img_filename"

    # Check if the image exists in the ../assets/ directory
    if [ ! -f "$img_full_path" ]; then
      echo "Image $img_full_path not found. Creating placeholder."

      # Create the ../assets directory if it doesn't exist
      mkdir -p "$dir/../assets"

      # Create a placeholder image with ImageMagick
      magick convert -size 800x600 xc:purple -gravity center \
        -pointsize 30 -fill white -annotate 0 "$img_filename" \
        "$img_full_path"
    fi
  done
done

This is useful if you want to write your instructions and take your screenshots separately.

Usage, assuming mpi.sh is executable and in your ~/bin/ directory.

cd labs
~/bin/mpi.sh 

The results look like...