Script to check for external links without targets

Signed-off-by: Dean Wampler <dean.wampler@ibm.com>

Author: deanwampler

check-external-links.sh

@@ -0,0 +1,81 @@
+#!/usr/bin/env zsh
+#---------------------------------------------------------------------------
+# Checks that all external links, those starting with http*, have "targets".
+#---------------------------------------------------------------------------
+
+default_path="docs"
+
+help() {
+	cat << EOF
+A fairly crude, but mostly effective tool that checks URLs in markdown
+files to make sure they all have "targets". It prints locations that
+appears to be missing "{:target=...}".
+
+It doesn't exit with an error if such links are found, because in some
+cases, this might be intentional.
+
+Usage: $script [-h|--help] [-n|--noop] [path1 ...]
+
+Where the arguments are the following:
+-h | --help            Print this message and exit
+-n | --noop            Just print the commands but don't make changes.
+-v | --verbose         Print the paths as they are processed. Mostly useful
+                       when no problems are found and you are paranoid nothing
+                       was checked. ;)
+path1 ...              Check these paths. Directories will be visited recursively.
+                       (Default: All markdown files under "$default_path")
+EOF
+}
+
+error() {
+	for arg in "$@"
+	do
+		echo "ERROR: $arg"
+	done
+	help
+	exit 1
+}
+
+paths=()
+: ${VERBOSE=}
+while [[ $# -gt 0 ]]
+do
+	case $1 in
+		-h|--h*)
+			help
+			exit 0
+			;;
+		-n|--n*)
+			NOOP=echo
+			;;
+		-v|--v*)
+			VERBOSE=echo
+			;;
+		-*)
+			error "Unrecognized option: $1"
+			;;
+		*)
+			paths+=("$1")
+			;;
+	esac
+	shift
+done
+
+[[ ${#paths[@]} -gt 0 ]] || paths=("$default_path")
+
+eg=$(which egrep)
+# Use a somewhat complicated script to find the URLs starting
+# with http, print only the matches and then filter out the 
+# URLs that contain "target". It won't work perfectly, but ...
+for path in "${paths[@]}"
+do
+	if [[ -n "$VERBOSE" ]]
+	then
+		dir=$([[ -d "$path" ]] && echo "(directory)")
+		echo "$path $dir"
+	fi
+	$eg -nHoR '\(https?[^)]+\)(\S*)' \
+		--include '*.markdown' --include '*.md' \
+		--exclude-dir '_site' --exclude-dir '_sass' \
+		$path | $eg -v target
+done