Improved utility script fetch-negistry.sh for fetching geolocation databases.

Added comments, added ability to receive and process command line arguments for better usability, few additional minor tweaks. (Redmine issue: #3443)

conf/cron_fetch-negistry-sh

@@ -8,4 +8,4 @@
 #
 
 # Run every day at 1am
-0 1 * * *   mentat /etc/mentat/scripts/fetch-negistry.sh
+0 1 * * *   root /etc/mentat/scripts/fetch-negistry.sh --quiet

scripts/fetch-negistry.sh

 #!/bin/bash
 #-------------------------------------------------------------------------------
-# Fetch whois data from CESNET`s Negistry service.
+# Utility script for fetching database from CESNET's Negistry service.
 #
 # Copyright (C) since 2011 CESNET, z.s.p.o
 # Use of this source is governed by the MIT license, see LICENSE file.
 #-------------------------------------------------------------------------------
 
-function die {
-    /bin/echo "ERROR: $1" 1>&2
+
+#
+# Helper functions for displaying information of various severity to the user.
+#
+function error {
+    /bin/echo -e "${RED}[ERROR] $1${NC}" 1>&2
     exit 1
 }
 
+function info {
+    if [ $FLAG_QUIET != 'YES' ]; then
+        /bin/echo "$1"
+    fi
+}
+
+function success {
+    if [ $FLAG_QUIET != 'YES' ]; then
+        /bin/echo -e "${GREEN}[SUCCESS] $1${NC}"
+    fi
+    exit 0
+}
+
+function usage {
+    /bin/echo ""
+    /bin/echo "Utility script for fetching database from CESNET's Negistry service."
+    /bin/echo ""
+    /bin/echo "Available options:"
+    /bin/echo "    -h | --help    display this help message and exit"
+    /bin/echo "    -d | --devel   fetch whois database from development server"
+    /bin/echo "    -q | --quiet   run in quiet mode, display only errors"
+    /bin/echo "    -s | --stub    install stub file in case of download error"
+    /bin/echo ""
+    /bin/echo "    -t=file"
+    /bin/echo "    --target=file  name of the target file (defaults to '/var/mentat/whois-negistry.json')"
+    /bin/echo ""
+}
+
+#-------------------------------------------------------------------------------
+
+
+#
+# Color code definitions for colored terminal output.
+# Source: https://stackoverflow.com/questions/5947742/how-to-change-the-output-color-of-echo-in-linux
+#
+RED='\033[0;31m'
+GREEN='\033[0;32m'
+ORANGE='\033[0;33m'
+NC='\033[0m'
+
+#
+# Define global variables.
+#
+FLAG_DEVEL=NO
+FLAG_QUIET=NO
+FLAG_STUB=NO
 LINK="https://negistry.cesnet.cz/db/api/v1/negistry-ripe-cesnet-ipranges.json"
 LINK_DEV="https://irgames.cesnet.cz/negistry/db/api/v1/negistry-ripe-cesnet-ipranges.json"
 TARGET="/var/mentat/whois-negistry.json"
 
-if [ $# -gt 0 ]; then
-    if [ $1 == "dev" ]; then
-        LINK=$LINK_DEV
-    fi
+
+#-------------------------------------------------------------------------------
+
+
+#
+# Command line argument parsing.
+# Source: https://stackoverflow.com/questions/192249/how-do-i-parse-command-line-arguments-in-bash
+#
+for i in "$@"
+do
+case $i in
+    -h|--help)
+    usage
+    exit 0
+    ;;
+    -d|--devel)
+    FLAG_DEVEL=YES
+    shift # past argument=value
+    ;;
+    -q|--quiet)
+    FLAG_QUIET=YES
+    shift # past argument=value
+    ;;
+    -s|--stub)
+    FLAG_STUB=YES
+    shift # past argument=value
+    ;;
+    -t=*|--target=*)
+    TARGET="${i#*=}"
+    shift # past argument=value
+    ;;
+    *)
+    usage
+    error "Invalid usage, unknown command line option '$i'"
+    ;;
+esac
+done
+
+
+#-------------------------------------------------------------------------------
+
+
+if [ $FLAG_DEVEL == 'YES' ]; then
+    LINK=$LINK_DEV
 fi
+info "Using remote server '$LINK'"
+info "Using local target file '$TARGET'"
+
 
-# Change to root directory
+#
+# Change to root directory.
+#
 cd /
 
-# Prefered method is curl
+#
+# Prefered method is curl.
+#
 if which curl > /dev/null
 then
     curl -4 --silent --insecure --output $TARGET $LINK
-# Wget fallback
+
+#
+# Use wget as fallback.
+#
 elif which wget > /dev/null; then
     wget -4 --no-verbose --no-check-certificate -O $TARGET $LINK
-# Report the error
+
 else
-    die "Unable to download whois dump file, missing curl or wget"
+    error "Unable to download Negistry whois database, missing 'curl' or 'wget' utilities"
+fi
+
+#
+# Check, that the download was successfull (target file must exist).
+#
+if [ ! -f "$TARGET" ]
+then
+    if [ $FLAG_STUB == 'YES' ]; then
+        info "Download of Negistry whois database failed, installing empty stub file '$TARGET'"
+        echo '{"__negistry_about__":"Stub negistry file"}' > "$TARGET"
+    else
+        error "Download of Negistry whois database failed, file '$TARGET' does not exist"
+    fi
 fi
 
-# Check, that the download was successfull (target file must not be older than 300s)
-if [ "$(( $(date +"%s") - $(date -r $TARGET +%s) ))" -gt "300" ]
+#
+# Check, that the download was successfull (target file must not be older than 60 s).
+#
+if [ "$(( $(date +"%s") - $(date -r $TARGET +%s) ))" -gt "60" ]
 then
-    die "Download of whois dump file failed, file is too old to be downloaded recently"
+    error "Download of Negistry whois database failed, file '$TARGET' is too old to be downloaded recently (last update at `date -r $TARGET`)"
 fi
 
-exit 0
+success "Successfully downloaded Negistry whois database into file '$TARGET' at `date`"