Script should not end terminal if not using bash (#5630)

* Script should not end terminal if not using bash

If the user hit the exit 0 (when using source) and
they did not use bash  terminal would exit.
The user would not know why the terminal exited.

Updated script to just check to see if there is bash available.

Set namespace to default if not specified

Add additional instructions when not running in bash

Document the use of the --namespace key

namespace is no longer positional but requires a --namespace or -ns key

* Update set-ver.sh

Make scdf the default namespace
[skip ci]
---------

Co-authored-by: Corneil du Plessis <[email protected]>

spring-cloud-dataflow-docs/src/main/asciidoc/appendix-local-k8s-development.adoc

@@ -78,7 +78,7 @@ Since these scripts export environmental variable they need to be executes as in
 
 [source,shell]
 ....
-source ./k8s/use-mk-docker.sh test-ns postgresql rabbitmq
+source ./k8s/use-mk-docker.sh postgresql rabbitmq --namespace test-ns
 ....
 
 ===== TMC or GKE Cluster in Cloud

src/deploy/k8s/set-ver.sh

@@ -64,6 +64,9 @@ while [ "$1" != "" ]; do
     shift
 done
 echo "Namespace: $NS"
+if [ "$NS" = "" ]; then
+    NS=scdf
+fi
 export NS
 if [ "$BROKER" != "" ]; then
     echo "BROKER: $BROKER"

src/deploy/k8s/use-mk-docker.sh

@@ -1,14 +1,10 @@
 #!/usr/bin/env bash
-(return 0 2>/dev/null) && sourced=1 || sourced=0
-if [ "$sourced" = "0" ]; then
-  echo "This script must be invoked using: source $0 $*"
-  exit 1
-fi
 if [ -z "$BASH_VERSION" ]; then
-    echo "This script requires Bash. Use: bash $0 $*"
-    exit 0
+    echo "This script requires Bash. For example:\n bash \n $0 $*"
+else
+    echo "Setting variables"
+    SCDIR=$(readlink -f "${BASH_SOURCE[0]}")
+    SCDIR=$(dirname "$SCDIR")
+    SCDIR=$(realpath $SCDIR)
+    source $SCDIR/use-mk.sh docker $*
 fi
-SCDIR=$(readlink -f "${BASH_SOURCE[0]}")
-SCDIR=$(dirname "$SCDIR")
-SCDIR=$(realpath $SCDIR)
-source $SCDIR/use-mk.sh docker $*