checks for sshpass only when necessary

Author: Yuri Escalianti

CHANGELOG

@@ -0,0 +1,5 @@
+2.1:
+
+- now checks for sshpass only when '-n' option is not set
+- improved error messages
+- added default Bash flags in README

README.md

@@ -10,8 +10,9 @@ $ runoverssh [OPTIONS] USERNAME COMMAND HOSTS...
 #### Default behavior:
 
 * Ask each `username@host` password at the start
-* SSH connections use the flags `-o ConnectTimeout=5 -o StrictHostKeyChecking=no`
-* Print all SSH output in the screen
+* SSH flags `-o ConnectTimeout=5 -o StrictHostKeyChecking=no`
+* Bash flags `-l`
+* Prints all SSH output in the screen
 
 #### Options:
 ```

runoverssh

@@ -21,10 +21,6 @@
 script_name=`basename "$0"`
 script_alias=`basename -s .sh "$0"`
 
-# Check dependencies
-command -v "ssh" >/dev/null 2>&1 || { echo >&2 "Error! You need to install 'ssh' to run this. Exiting."; exit 1; }
-command -v "sshpass" >/dev/null 2>&1 || { echo >&2 "Error! You need to install 'sshpass' to run this. Exiting."; exit 1; }
-
 # Print help
 function print_help {
   echo "Usage: ${script_name} [OPTIONS] USERNAME COMMAND HOSTS..."
@@ -60,7 +56,7 @@ function print_help {
 
 # Standard parameters
 username=""
-command=""
+remote_command=""
 hosts=()
 
 # Optional parameters
@@ -70,7 +66,7 @@ log_enabled=""  # -l | --log
 log_file="${script_alias}.log"  # --logfile
 global_pw=""  # -g, --globalpw
 passwords=()
-no_pw="" 
+no_pw=""  # -n, --nopw
 ssh_flags="-o ConnectTimeout=5 -o StrictHostKeyChecking=no"   # --sshflags
 bash_flags="-l"  # --bashflags
 quiet_enabled="" # -q | --quiet
@@ -135,7 +131,7 @@ for parameter do
         ;;
       *)
         if [[ "${parameter}" == "--"* ]] || [[ "${parameter}" == "-"* ]]; then
-          echo "Error! Invalid option '${parameter}'. Exiting."
+          echo "Error: invalid option '${parameter}'. Exiting."
           exit 1
         fi
 
@@ -144,8 +140,8 @@ for parameter do
         if [ -z "${username}" ]; then
           username=${parameter}
         else
-          if [ -z "${read_commands_from_file}" ] && [ -z "${command}" ]; then
-            command="${parameter}"
+          if [ -z "${read_commands_from_file}" ] && [ -z "${remote_command}" ]; then
+            remote_command="${parameter}"
           else
             if [ -z "${read_hosts_from_file}" ]; then
               hosts+=("${parameter}")
@@ -161,35 +157,35 @@ done
 # Check parameter and argument consistency
 
 if [ -n "${waiting_option}" ]; then
-  echo "Error! Missing value for '${waiting_option}' parameter. Exiting."
+  echo "Error: missing value for '${waiting_option}' parameter. Exiting."
   exit 1
 fi
 
 if [ -z "${username}" ]; then
-  echo "Error! Please specify the username to be used in SSH. Exiting."
+  echo "Error: please specify the username to be used in SSH. Exiting."
   exit 1
 fi
 
-if [ -z "${read_commands_from_file}" ] && [ -z "${command}" ] ; then
-  echo "Error! Please specify the command or script file ('-s') to be executed over SSH. Exiting."
+if [ -z "${read_commands_from_file}" ] && [ -z "${remote_command}" ] ; then
+  echo "Error: please specify the command or script file ('-s') to be executed over SSH. Exiting."
   exit 1
 fi
-if [ -n "${read_commands_from_file}" ] && [ -n "${command}" ] ; then
-  echo "Error! Parameter conflict: do not put a command as argument when also specifying a script as parameter. Exiting."
+if [ -n "${read_commands_from_file}" ] && [ -n "${remote_command}" ] ; then
+  echo "Error: parameter conflict: do not put a command as argument when also specifying a script as parameter. Exiting."
   exit 1
 fi
 
 if [ -z "${read_hosts_from_file}" ] && [ ${#hosts[@]} -eq 0 ]; then
-  echo "Error! Please specify at least one target host or use the '--hostsfile' option. Exiting."
+  echo "Error: please specify at least one target host or use the '--hostsfile' option. Exiting."
   exit 1
 fi
 if [ -n "${read_hosts_from_file}" ] && [ ${#hosts[@]} -gt 0 ]; then
-  echo "Error! Parameter conflict: do not list hosts as arguments when also specifying a hostsfile as parameter. Exiting."
+  echo "Error: parameter conflict: do not list hosts as arguments when also specifying a hostsfile as parameter. Exiting."
   exit 1
 fi
 
 if [ -n "${global_pw}" ] && [ -n "${no_pw}" ]; then
-  echo "Error! Parameter conflict: do not set the 'no password' option when also specifying a global password. Exiting.";
+  echo "Error: parameter conflict: do not set the 'no password' option when also specifying a global password. Exiting.";
   exit 1
 fi
 
@@ -206,7 +202,7 @@ fi
 
 # Check log file
 if [ -d "${log_file}" ]; then
-  echo "Error! Log file '${log_file}' is a directory. Exiting."
+  echo "Error: log file '${log_file}' is a directory. Exiting."
   exit 1
 fi
 
@@ -220,6 +216,14 @@ if [ -n "${read_hosts_from_file}" ]; then
   done<"${read_hosts_from_file}"
 fi
 
+# Check dependencies
+command -v "ssh" >/dev/null 2>&1 || { echo >&2 "Error: program 'ssh' not found. Exiting."; exit 1; }
+
+# Check for sshpass if the option '-n' is not set
+if [ -z "${no_pw}" ]; then
+  command -v "sshpass" >/dev/null 2>&1 || { echo >&2 "Error: program 'sshpass' not found (use the '-n' option to use 'ssh' instead). Exiting."; exit 1; }
+fi
+
 
 # Get the SSH passwords (unless 'no password' is set)
 
@@ -271,9 +275,9 @@ if [ -n "${no_pw}" ]; then
       fi
     else
       if [ -n "${quiet_enabled}" ]; then
-        ssh ${ssh_flags} ${username}@${host} "bash ${bash_flags} -c \"${command}\"" >> "${log_file}"
+        ssh ${ssh_flags} ${username}@${host} "bash ${bash_flags} -c \"${remote_command}\"" >> "${log_file}"
       else
-        ssh ${ssh_flags} ${username}@${host} "bash ${bash_flags} -c \"${command}\"" | tee -a "${log_file}"
+        ssh ${ssh_flags} ${username}@${host} "bash ${bash_flags} -c \"${remote_command}\"" | tee -a "${log_file}"
       fi
     fi
   done
@@ -290,9 +294,9 @@ else
       fi
     else
       if [ -n "${quiet_enabled}" ]; then
-        sshpass -p "${passwords[$i]}" ssh ${ssh_flags} ${username}@${host} "bash ${bash_flags} -c \"${command}\"" >> "${log_file}"
+        sshpass -p "${passwords[$i]}" ssh ${ssh_flags} ${username}@${host} "bash ${bash_flags} -c \"${remote_command}\"" >> "${log_file}"
       else
-        sshpass -p "${passwords[$i]}" ssh ${ssh_flags} ${username}@${host} "bash ${bash_flags} -c \"${command}\"" | tee -a "${log_file}"
+        sshpass -p "${passwords[$i]}" ssh ${ssh_flags} ${username}@${host} "bash ${bash_flags} -c \"${remote_command}\"" | tee -a "${log_file}"
       fi
     fi