improved coding standards. options parsing. verbose logging

lib/main.sh

@@ -3,11 +3,10 @@ for util in ./lib/utils/*.sh; do source $util; done
 
 # init
 __METRICS=()
-__TEMP_DIR=$(make_temp_dir)
 
-# load reporter
 
 main_load () {
+  # load reporter
   source ./reporters/${REPORTER}.sh
   copy_function init      __r_${REPORTER}_init
   copy_function report    __r_${REPORTER}_report
@@ -34,6 +33,14 @@ main_load () {
 }
 
 main_init () {
+  TEMP_DIR=$(make_temp_dir)
+
+  # register trap
+  trap '
+    main_terminate
+    trap - SIGTERM && kill -- -$$ SIGINT SIGTERM EXIT
+  ' SIGINT SIGTERM EXIT
+
   # init reporter
   if is_function __r_${REPORTER}_init; then
     __r_${REPORTER}_init
@@ -49,19 +56,6 @@ main_init () {
   done
 }
 
-main_docs () {
-  echo "Available metrics:"
-  for metric in ${__METRICS[@]}; do
-    if ! is_function __m_${metric}_docs; then
-      continue
-    fi
-
-    echo "[$metric]"
-    __m_${metric}_docs
-    echo
-  done
-}
-
 main_collect () {
   # used by metrics to return results
   report () {
@@ -105,4 +99,22 @@ main_terminate () {
   if is_function __r_${REPORTER}_terminate; then
     __r_${REPORTER}_terminate
   fi
+
+  # delete temporary directory
+  if [ ! -z $TEMP_DIR ] && [ -d $TEMP_DIR ]; then
+    rmdir $TEMP_DIR
+  fi
+}
+
+main_docs () {
+  echo "Available metrics:"
+  for metric in ${__METRICS[@]}; do
+    if ! is_function __m_${metric}_docs; then
+      continue
+    fi
+
+    echo "[$metric]"
+    __m_${metric}_docs
+    echo
+  done
 }

lib/utils/verbose.sh

@@ -0,0 +1,16 @@
+VERBOSE_MODE=false
+
+verbose_on () {
+  VERBOSE_MODE=true
+}
+
+verbose_off () {
+  VERBOSE_MODE=true
+}
+
+verbose () {
+  if [ $VERBOSE_MODE = "false" ]; then
+    return
+  fi
+  echo "$@"
+}

metrics/cpu.sh

@@ -1,7 +1,7 @@
 #!/bin/sh
 
 collect () {
-  report $(ps aux | awk '{sum+=$3} END {printf "%.1f\n", sum}' | tail -n 1)
+  report $(ps aux | awk '{ sum+=$3 } END { printf "%.1f\n", sum }' | tail -n 1)
 }
 
 docs () {

metrics/disk_io.sh

@@ -8,7 +8,7 @@ init () {
       DISK_IO_MOUNTPOINT="/dev/vda"
     fi
   fi
-  readonly __disk_io_fifo=$__TEMP_DIR/disk_io
+  readonly __disk_io_fifo=$TEMP_DIR/disk_io
   mkfifo $__disk_io_fifo
   __disk_io_bgproc &
 }
@@ -16,7 +16,7 @@ init () {
 if is_osx; then
   __disk_io_bgproc () {
     iostat -K -d -w $INTERVAL $DISK_IO_MOUNTPOINT | while read line; do
-      echo $line | awk '{print $3}' > $__disk_io_fifo
+      echo $line | awk '{ print $3 }' > $__disk_io_fifo
     done
   }
 else
@@ -26,11 +26,11 @@ else
 fi
 
 collect () {
-  report $(cat $__disk_io_fifo)
+  report $(cat < $__disk_io_fifo)
 }
 
 terminate () {
-  if [ ! -z $__disk_io_fifo ] && [ -f $__disk_io_fifo ]; then
+  if [ ! -z $__disk_io_fifo ] && [ -p $__disk_io_fifo ]; then
     rm $__disk_io_fifo
   fi
 }

metrics/disk_usage.sh

@@ -12,7 +12,7 @@ init () {
 
 collect () {
   report $(df | awk -v disk_regexp="^$DISK_USAGE_MOUNTPOINT" \
-                  '$0 ~ disk_regexp {printf "%.1f", $5}')
+                                '$0 ~ disk_regexp { printf "%.1f", $5 }')
 }
 
 docs () {

metrics/memory.sh

@@ -7,13 +7,14 @@ if is_osx; then
 
   collect () {
     report $(vm_stat | awk -v total_memory=$__memory_os_memsize \
-            'BEGIN {FS="   *"; pages=0}
+            'BEGIN { FS="   *"; pages=0 }
-             /Pages (free|inactive|speculative)/ {pages+=$2}
+            /Pages (free|inactive|speculative)/ { pages+=$2 }
-             END {printf "%.1f", 100 - (pages * 4096) / total_memory * 100.0}')
+            END { printf "%.1f", 100 - (pages * 4096) / total_memory * 100.0 }')
   }
 else
   collect () {
-    report $(free | awk '/buffers\/cache/{printf "%.1f", 100 - $4 / ($3 + $4) * 100.0}')
+    report $(free | awk '/buffers\/cache/
+                          { printf "%.1f", 100 - $4 / ($3 + $4) * 100.0 }')
   }
 fi
 

metrics/network_io.sh

@@ -13,19 +13,19 @@ init () {
 
 if is_osx; then
   __network_io_collect () {
-    netstat -bI $NETWORK_IO_INTERFACE | \
+    netstat -bI $NETWORK_IO_INTERFACE |
-                    awk "/$NETWORK_IO_INTERFACE/"'{print $7" "$10; exit}'
+                    awk "/$NETWORK_IO_INTERFACE/"'{ print $7" "$10 }'
   }
 else
   __network_io_collect () {
     cat /proc/net/dev | awk -v iface_regex="$NETWORK_IO_INTERFACE:" \
-                          '$0 ~ iface_regex {print $2" "$10}'
+                                    '$0 ~ iface_regex { print $2" "$10 }'
   }
 fi
 
 __network_io_calc_kBps() {
   echo $1 $2 | awk -v divisor=$__network_io_divisor \
-                '{printf "%.2f", ($1 - $2) / divisor}'
+                '{ printf "%.2f", ($1 - $2) / divisor }'
 }
 
 collect () {

metrics/swap.sh

@@ -2,11 +2,12 @@
 
 if is_osx; then
   collect () {
-    report $(sysctl -n vm.swapusage | awk '{printf "%.1f", $6 / $3 * 100.0}')
+    report $(sysctl -n vm.swapusage |
+                awk '{ if ($3 == 0) exit; printf "%.1f", $6 / $3 * 100.0 }')
   }
 else
   collect () {
-    report $(free | awk '/Swap/{printf "%.1f", $3/$2 * 100.0}')
+    report $(free | awk '/Swap/{ printf "%.1f", $3/$2 * 100.0 }')
   }
 fi
 

reporters/file.sh

@@ -4,7 +4,7 @@ report () {
   local METRIC=$1
   local VALUE=$2
   local DATE=$(iso_date)
-  echo $DATE $METRIC: $VALUE >> $FILE_LOCATION
+  echo "$DATE $METRIC: $VALUE" >> $FILE_LOCATION
 }
 
 init () {

sysmetricsd.sh

@@ -2,16 +2,62 @@
 
 # config
 INTERVAL=1
-REPORTER=file
+REPORTER=stdout
 
-# register trap
-trap '
-  main_terminate
-  trap - SIGTERM && kill -- -$$ SIGINT SIGTERM EXIT
-' SIGINT SIGTERM EXIT
 
-# load and start main routine
+# handle opts
+opts_spec=":dvh-:"
+opt_docs=false
+opt_verbose=false
+
+usage () {
+  echo "usage: $0 [-d] [-h]"
+}
+
+help () {
+  echo "TODO"
+}
+
+while getopts "$opts_spec" opt; do
+  case "${opt}" in
+    d)
+      opt_docs=true
+      ;;
+    v)
+      opt_verbose=true
+      ;;
+    h)
+      help
+      exit
+      ;;
+    *)
+      usage
+      exit 1
+      ;;
+  esac
+done
+shift $((OPTIND-1))
+
+
+# run
 source ./lib/main.sh
+
+if [ $opt_verbose = "true" ]; then
+  verbose_on
+  verbose "Started in verbose mode"
+fi
+verbose "OS detected: $OS_TYPE"
+
 main_load
+verbose "Metrics loaded: ${__METRICS[@]}"
+
+if [ "$opt_docs" = true ]; then
+  main_docs
+  exit
+fi
+
 main_init
+verbose "Metrics initialized"
+
+verbose "Collecting metrics every $INTERVAL second(s)"
 main_collect