Add connection check at the end

On Windows platform, target host restart is required after an install
step. If the machine takes long to be available again, this can cause
problems further down the "pipeline". So before proceding further,
check the ssh connection is back up.

entrypoint.sh

@@ -25,6 +25,15 @@ $(scp_to_cmd "${ASSETS_FOLDER}/*" "${TARGET_FOLDER}/")
 # Exec command
 $(ssh_cmd "$@")
 
+# Check ssh connection to target host
+CHECK_CONNECTION_ATTEMPTS=${CHECK_CONNECTION_ATTEMPTS:-30}
+CHECK_CONNECTION_DELAY=${CHECK_CONNECTION_DELAY:-10}
+check_connection  ${CHECK_CONNECTION_ATTEMPTS} ${CHECK_CONNECTION_DELAY}
+if [[ $? -gt 0 ]]
+then
+    exit 1
+fi
+
 # Copy results
 if [[ ! -z "${TARGET_RESULTS+x}" ]]; then
     # If exec create some reuslts we define the env and they will be copied to OUTPUT_FOLDER

lib/remote.sh

@@ -28,9 +28,38 @@ connect_options() {
     options="$options -o UserKnownHostsFile=/dev/null"
     options="$options -o ServerAliveInterval=30"
     options="$options -o ServerAliveCountMax=1200"
+    options="$options -o BatchMode=yes"
+    options="$options -o ConnectTimeout=3"
     echo $options
 }
 
+# If restart is involved, it can take a moment for the target host to become available again
+# Check the connection to the host; "delay" in seconds, "repeats" in number of reps
+# Run as: check_connection <repeats int> <delay int>
+# e.g. check_connection 30 10
+check_connection() {
+    repeats=$1
+    while [[ $repeats -gt 0 ]]
+    do
+        ssh_cmd "pwd"
+        if [[ $? -gt 0 ]] 
+        then
+            echo "reps remaining: $repeats" >&2
+            ((repeats--))
+            sleep $2
+        else
+            break
+        fi
+    done
+    # fail or pass the check
+    if [[ $repeats -gt 0 ]]
+    then
+        return 0
+    else
+        return 1
+    fi          
+}
+
 # Define remote connection
 uri () {
     local remote="${TARGET_HOST_USERNAME}@${TARGET_HOST}"