mnadel · February 14, 2023 07:36 · May 21, 2017 · Mar 21, 2017
diff --git a/kcdo b/kcdo
@@ -5,22 +5,26 @@ PROGNAME=$(basename $0)
 function usage {
     echo "usage: $PROGNAME [-n NAMESPACE] [-m MAX-PODS] -s SERVICE -- COMMAND"
     echo "  -s SERVICE   K8s service, i.e. a pod selector (required)"
+    echo "     COMMAND   Command to execute on the pods"
     echo "  -n NAMESPACE K8s namespace (optional)"
-    echo "  -m MAX-PODS  Max number of pods to run on (optional; default = all)"
+    echo "  -m MAX-PODS  Max number of pods to run on (optional; default=all)"
     echo "  -q           Quiet mode"
-    echo "     COMMAND   Command to execute on the pods"
+    echo "  -d           Dry run (don't actually exec)"
 }
 
 function header {
     if [ -z $QUIET ]; then
         >&2 echo "###"
-        >&2 echo "### $PROGNAME $1 $2"
+        >&2 echo "### $PROGNAME $*"
         >&2 echo "###"
     fi
 }
 
-while getopts :n:s:m:q opt; do
+while getopts :n:s:m:qd opt; do
     case $opt in
+        d)
+            DRYRUN=true
+            ;;
         q)
             QUIET=true
             ;;
@@ -47,7 +51,7 @@ fi
 
 shift $(expr $OPTIND - 1)
 
-while test $# -gt 0; do
+while test "$#" -gt 0; do
     if [ "$REST" == "" ]; then
         REST="$1"
     else
@@ -57,6 +61,11 @@ while test $# -gt 0; do
     shift
 done
 
+if [ "$REST" == "" ]; then
+    usage
+    exit 1
+fi
+
 PODS=()
 
 for pod in $(kubectl $NAMESPACE get pods --output=jsonpath={.items..metadata.name}); do
@@ -66,13 +75,22 @@ for pod in $(kubectl $NAMESPACE get pods --output=jsonpath={.items..metadata.nam
     fi
 done
 
+if [ ${#PODS[@]} -eq 0 ]; then
+    echo "service not found in ${NAMESPACE:-default}: $SERVICE"
+    exit 1
+fi
+
 if [ ! -z $MAX_PODS ]; then
     PODS=("${PODS[@]:1:$MAX_PODS}")
 fi
 
-header exec "$REST"
+header "{pods: ${#PODS[@]}, command: \"$REST\"}"
 
-for pod in ${PODS[@]}; do
-    header pod $pod
-    kubectl $NAMESPACE exec $pod -- $REST
-done
+for i in "${!PODS[@]}"; do
+    pod=${PODS[$i]}
+    header "{pod: \"$(($i + 1))/${#PODS[@]}\", name: \"$pod\"}"
+
+    if [ "$DRYRUN" != "true" ]; then
+        kubectl $NAMESPACE exec $pod -- $REST
+    fi
+done
diff --git a/kcdo b/kcdo
@@ -0,0 +1,78 @@
+#!/usr/bin/env bash
+
+PROGNAME=$(basename $0)
+
+function usage {
+    echo "usage: $PROGNAME [-n NAMESPACE] [-m MAX-PODS] -s SERVICE -- COMMAND"
+    echo "  -s SERVICE   K8s service, i.e. a pod selector (required)"
+    echo "  -n NAMESPACE K8s namespace (optional)"
+    echo "  -m MAX-PODS  Max number of pods to run on (optional; default = all)"
+    echo "  -q           Quiet mode"
+    echo "     COMMAND   Command to execute on the pods"
+}
+
+function header {
+    if [ -z $QUIET ]; then
+        >&2 echo "###"
+        >&2 echo "### $PROGNAME $1 $2"
+        >&2 echo "###"
+    fi
+}
+
+while getopts :n:s:m:q opt; do
+    case $opt in
+        q)
+            QUIET=true
+            ;;
+        m)
+            MAX_PODS=$OPTARG
+            ;;
+        n)
+            NAMESPACE="-n $OPTARG"
+            ;;
+        s)
+            SERVICE=$OPTARG
+            ;;
+        \?)
+            usage
+            exit 0
+            ;;
+    esac
+done
+
+if [ -z $SERVICE ]; then
+    usage
+    exit 1
+fi
+
+shift $(expr $OPTIND - 1)
+
+while test $# -gt 0; do
+    if [ "$REST" == "" ]; then
+        REST="$1"
+    else
+        REST="$REST $1"
+    fi
+
+    shift
+done
+
+PODS=()
+
+for pod in $(kubectl $NAMESPACE get pods --output=jsonpath={.items..metadata.name}); do
+    echo $pod | grep -qe "^$SERVICE" >/dev/null 2>&1
+    if [ $? -eq 0 ]; then
+        PODS+=($pod)
+    fi
+done
+
+if [ ! -z $MAX_PODS ]; then
+    PODS=("${PODS[@]:1:$MAX_PODS}")
+fi
+
+header exec "$REST"
+
+for pod in ${PODS[@]}; do
+    header pod $pod
+    kubectl $NAMESPACE exec $pod -- $REST
+done