From: Andrew Lorimer <andrew@lorimer.id.au>
Date: Sun, 14 Aug 2022 12:06:08 +0000 (+1000)
Subject: improve webp-convert.sh
X-Git-Url: https://git.lorimer.id.au/scripts.git/diff_plain

improve webp-convert.sh
---

diff --git a/webp-convert.sh b/webp-convert.sh
index be7d1f7..acdec25 100755
--- a/webp-convert.sh
+++ b/webp-convert.sh
@@ -4,57 +4,291 @@
 #
 # Search through HTML and PHP files in a directory, get a list of the image
 # files used (jpg/png), and convert these to webp in the same directory as
-# the originals. Can be used with a rewrite rule on the web server to 
-# serve the webp file when the original is requested.
+# the originals. Alternatively, convert all jpg/png files in a directory to 
+# webp. Can be used with a rewrite rule on the web server to serve the webp 
+# file when the original is requested.
 #
 # Andrew Lorimer, January 2021
 #
 
-docroot=$1
-if [ ! $docroot ]; then
-  docroot=.
-fi;
+usagelong="\e[1mUSAGE:\e[0m $(basename "$0") [OPTIONS] [DIRECTORY]
 
+\e[1mOPTIONS:\e[0m
+  -a|--all
+    Convert all image files in DIRECTORY to webp. This is the default mode. 
+    This is mutually exclusive with -s|--scan.
+
+  -s|--scan
+    Scan all files with .php or .html extension in DIRECTORY for <img> tags 
+    and convert source images to webp. This is mutually exclusive with 
+    -a|--all.
+
+  -o|--overwrite
+    Convert all files even if the output filename exists (the default is to 
+    ignore files for which a webp already exists). When calculating space 
+    savings of files which overwrite existing ones, the saving is relative to 
+    the source file, not the file that is overwritten.
+
+  -q|--quiet
+    Do not print any output (apart from errors). Mutually exclusive with 
+    -v|--verbose.
+
+  -v|--verbose
+    Print extra output for each file. Mutually exclusive with -q|--quiet.
+
+  -d|--dry
+    Dry run - search for files and attempt to convert them but do not make any
+    permanent changes. Used for checking possible space savings.
+
+  -h|--help
+    Print this help message and exit.
+
+\e[1mDIRECTORY:\e[0m
+    Directory in which to search for PHP or HTML files (in -s|--scan mode) or 
+    image files (in -a|--all mode).
+
+Converts JPG and PNG files to WebP using ImageMagick's convert(1). Optionally 
+searches for source file in a directory or searches through HTML/PHP files in 
+a directory to find references to source files.\n"
+
+usageshort="\e[1mUSAGE:\e[0m
+  $(basename "$0") [MODE] [OPTIONS] [DIRECTORY]
+
+For more information, see \e[34m$(basename "$0") --help\e[0m\n"
+
+modehint="\x1b[31m-s|--scan and -a|--all cannot be specified simultaneously\x1b[0m\n\n$usageshort"
+verbosityhint="\x1b[31m-q|--quiet and -v|--verbose cannot be specified simultaneously\x1b[0m\n\n$usageshort"
+dryhint="\x1b[33mDry run mode\x1b[0m\n"
+overwritehint="\x1b[33mOverwriting existing files\x1b[0m\n"
+invalidhint="\x1b[31mInvalid argument $1\x1b[0m\n\n$usageshort"
+
+if (( $# > 5)); then
+  printf "$usageshort"
+  exit 1
+fi
+
+mode=-1       # -1: initial, 0: all (default), 1: scan
+overwrite=0
+dry=0
+verbosity=-1  # -1: initial, 0: quiet, 1: normal, 2: verbose
+directory=""
+
+while [ $# -gt 0 ]; do
+  case "$1" in
+    -a|--all)
+      if [[ $mode == 1 ]]; then
+        printf "$modehint"
+        exit 1
+      fi
+      mode=0
+      shift
+      ;;
+    -s|--scan)
+      if [[ $mode == 0 ]]; then
+        printf "$modehint"
+        exit 1
+      fi
+      mode=1
+      shift
+      ;;
+    -o|--overwrite)
+      overwrite=1
+      shift
+      ;;
+    -q|--quiet)
+      if [[ $verbosity == 2 ]]; then
+        printf "$verbosityhint"
+        exit 1
+      fi
+      verbosity=0
+      shift
+      ;;
+    -v|--verbose)
+      if [[ $verbosity == 0 ]]; then
+        printf "$verbosityhint"
+        exit 1
+      fi
+      verbosity=2
+      shift
+      ;;
+    -d|--dry)
+      dry=1
+      shift
+      ;;
+    -h|--help)
+      printf "$usagelong"
+      exit
+      ;;
+    *)
+      if [[ "$directory" = "" && "$1" != -* ]]; then
+        directory=$1
+        shift
+      else
+        printf "$invalidhint"
+        exit 1
+      fi
+      ;;
+  esac
+done
+
+# Set mode to 0 (all) if not specified
+if [[ $mode == -1 ]]; then
+  mode=0
+fi
+
+# Set directory to . if not specified
+if [[ "$directory" = "" ]]; then
+  directory="."
+fi
+
+# Set verbosity to 1 if not specified
+if [[ $verbosity == -1 ]]; then
+  verbosity=1
+fi
+
+# Indicate that we are running in dry mode
+if [[ $verbosity > 0 && $dry == 1 ]]; then
+  printf "$dryhint"
+fi
+
+# Indicate that we will overwrite
+if [[ $verbosity > 0 && $overwrite == 1 ]]; then
+  printf "$overwritehint"
+fi
+
+savings=()
+savings_total=0
+found_count=0
 convert_count=0
 larger_count=0
+failed_count=0
 
-echo "Converting files in $docroot"
 convert_webp () {
   # Perform the conversion. Takes input filename, output filename.
+
+  # Set destination (user-supplied is quoted to handle spaces properly)
+  if [[ $dry == 1 ]]; then
+    suffix="/tmp/webp-convert.webp"
+  else
+    suffix="$2"
+  fi
+
   if [[ "$1" == *.png ]]; then
     # PNG conversion
-    convert "$1" -quality 75 -define webp:lossless=true "$2"
-    echo "Converted $1 to $2"
+    convert "$1" -quality 75 -define webp:lossless=true $suffix
+    convert_status=$?
   else
     # JPG conversion
-    convert "$1" -quality 75 "$2"
-    echo "Converted $1 to $2"
+    convert "$1" -quality 75 $suffix
+    convert_status=$?
+  fi
+
+  # Check status code & print feedback
+  if [[ $convert_status == 0 ]]; then
+    # Successful
+    ((convert_count+=1))
+    if [[ $verbosity > 1 ]]; then
+      echo "Converted $1 to $2"
+    fi
+  else
+    # Failed
+    ((failed_count+=1))
+    if [[ $verbosity > 0 ]]; then
+      printf "\x1b[31mFailed to convert $1 to $2\x1b[0m\n"
+    fi
+    return 1  # Return because we don't need to check file size
   fi
-  ((convert_count+=1))
 
   # Check if webp is actually smaller than original and remove if not
   orig_size=$(stat -c%s "$1")
-  webp_size=$(stat -c%s "$2")
+  if [[ $dry ]]; then
+    webp_size=$(stat -c%s $suffix)
+  else
+    webp_size=$(stat -c%s "$2")
+  fi
   if (( webp_size > orig_size )); then
-    rm $2
-    echo "Removed $2 as it was larger than $1 ($webp_size > $orig_size)"
+    if [[ ! $dry ]]; then
+      rm $2
+    fi
+    if [[ $verbosity > 0 ]]; then
+      printf "\x1b[33mRemoved $2 as it was larger than $1 ($webp_size > $orig_size)\x1b[0m\n"
+    fi
     ((larger_count+=1))
     return 1
   fi
+
+  # Calculate file size saving
+  saving=$((orig_size - webp_size))
+  savings+=($saving)
+  ((savings_total+=$saving))
+  
   return 0
 }
 
-while read -r srcfile; do
-    while IFS= read -r file; do
-      file_path=$(echo $file | sed "s|^.|$docroot/|")
-      webp_path=$(sed 's/\.[^.]*$/.webp/' <<< "$file_path")
-      
-      # Convert if not already converted
-      if [ ! -f "$webp_path" ]; then
-        convert_webp $file_path $webp_path
+if [[ $mode == 0 ]]; then
+  # Convert all images in directory
+  if [[ $verbosity > 1 ]]; then
+    printf "Converting image files in $directory\n"
+  fi
+  for file_path in $(find $directory -type f -and \( -iname '*.jpg' -o -iname '*.jpeg' \)); do
+    ((found_count+=1))
+    webp_path=$(sed 's/.jpe\?g$/.webp/' <<< "$file_path")
+    if [[ ! -f "$webp_path"  || $overwrite == 1 ]]; then
+      convert_webp $file_path $webp_path
+    fi
+  done
+else
+  # Scan php and html files for images to convert
+  while read -r srcfile; do
+      if [[ $verbosity > 1 ]]; then
+        printf "Scanning for image files referenced in $srcfile\n"
       fi
-    done < <(sed -n "s:.*<img src=\"\([^\"]*\.\(jpe\?g\|png\)\)\".*:\1:p" $srcfile)
-done <<< "$(find $docroot -type f -and \( -iname "*.php" -o -iname "*.html" \))"
+      while IFS= read -r file; do
+        ((found_count+=1))
+        file_path=$(echo $file | sed "s|^.|$directory/|")
+        webp_path=$(sed 's/\.[^.]*$/.webp/' <<< "$file_path")
+        
+        # Convert if not already converted
+        if [[ ! -f "$webp_path"  || $overwrite == 1 ]]; then
+          convert_webp $file_path $webp_path
+        fi
+      done < <(sed -n "s:.*<img src=\"\([^\"]*\.\(jpe\?g\|png\)\)\".*:\1:p" $srcfile)
+  done <<< "$(find $directory -type f -and \( -iname "*.php" -o -iname "*.html" \))"
+fi
 
+# Calculate statistics
 net=$((convert_count-larger_count))
-echo "Converted $convert_count of which $larger_count were larger than the original (net $net)"
+existing=$((found_count-convert_count))
+if [[ $net > 0 ]]; then
+  savings_avg=$((savings_total/net))
+else
+  savings_avg=0
+fi
+
+# Convert sizes to human-readable units if numfmt available
+if command -v numfmt &> /dev/null; then
+  savings_total=$(numfmt --to iec $savings_total)
+  savings_avg=$(numfmt --to iec $savings_avg)
+else
+  savings_total="$savings_total B"
+  savings_avg="$savings_avg B"
+fi
+
+# Print statistics
+if [[ $verbosity > 0 ]]; then
+  printf "\x1b[32m$found_count found\n"
+  if [[ $failed_count > 0 ]]; then
+    printf "\x1b[31m$failed_count failed\n"
+  fi
+  printf "\x1b[32m$convert_count converted
+$net smaller than original
+$savings_total saved
+$savings_avg saved average per file\n\x1b[0m"
+fi
+
+# Set exit code
+if [[ $failed_count > 0 ]]; then
+  exit 1
+else
+  exit 0
+fi