Update the license check

- The current license check script works only for a single year
- This commit modifies the script to being able to validate headers
  with a different date.

Author: Franck Rupin

scripts/licensecheck.sh

@@ -1,15 +1,34 @@
-#!/bin/bash
+#!/bin/bash 
 
 # Verify that the correct license block is present in all Go source
 # files.
-EXPECTED=$(cat ./scripts/license.txt)
+LICENSE=./scripts/license.txt
+NB_LINES=$(cat $LICENSE| wc -l)
+EXPECTED=$(head -$NB_LINES $LICENSE | tail +2)
+
+# Update the string if there is a new year to consider
+COPYRIGHT_YEARS="2017 2021"
 
 # Scan each Go source file for license.
 EXIT=0
 GOFILES=$(find . -name "*.go")
 
 for FILE in $GOFILES; do
-	BLOCK=$(head -n 14 $FILE)
+	# Start validating the Copyright line of for each header.
+	# Years can change from a source file to another.
+	read -r -a COPYRIGHT_TOKENS <<< $(head -n 1 $FILE |awk '{print $2 " " $3 " " $4}')
+	if [ "${COPYRIGHT_TOKENS[0]}" != "Copyright" ]; then
+		echo "Bad Copyright token ${COPYRIGHT_TOKENS[0]} in $FILE"	
+		EXIT=1
+	elif [ $(echo $COPYRIGHT_YEARS | grep -c ${COPYRIGHT_TOKENS[1]}) != "1" ]; then
+		echo "Bad Year token ${COPYRIGHT_TOKENS[1]} in $FILE"	
+		EXIT=1
+	elif [ "${COPYRIGHT_TOKENS[2]}" != "DigitalOcean." ]; then
+		echo "Bad DigitalOcean token ${COPYRIGHT_TOKENS[2]} in $FILE"	
+		EXIT=1
+	fi
+
+	BLOCK=$(head -n 14 $FILE|tail +2)
 
 	if [ "$BLOCK" != "$EXPECTED" ]; then
 		echo "file missing license: $FILE"