Refactor and rename

 - Changes name of script
 - Makes sure the machine exists, and starts it if necessary
 - Loads itself as the bash rc script

guides/docker/linux/machine/README.md

@@ -76,5 +76,5 @@ exit
 
 ## Step 5. Easier loading of the dev machine
 
-To prevent having to type 'bash' and 'eval' as above, run [this bash script](./load-dev-machine.sh) instead. It will drop you into a new shell with the 'dev' machine loaded, and modify your prompt to signify you are using this new machine. Just run `exit` to drop back into your previous shell.
+To prevent having to type 'bash' and 'eval' as above, run [this bash script](./load-machine.sh) instead. It will drop you into a new shell with the 'dev' machine loaded, and modify your prompt to signify you are using this new machine. Just run `exit` to drop back into your previous shell.
 

guides/docker/linux/machine/load-machine.sh

@@ -0,0 +1,46 @@
+#!/usr/bin/env bash
+# load-machine.sh - load a docker machine and change PS1 prompt to include machine name
+# Copyright (C) 2018 Peter Willis <peterwwillis@gmail.com>
+# 
+# Usage:
+#       $ ./load-machine.sh
+#   OR 
+#       $ ./load-machine.sh machine-name
+# 
+
+[ $# -gt 0 ] && DM_NAME="$1"
+
+# The following will evaluate a PROMPT_COMMAND (if it was set),
+# then it will replace any '\h' entry in the PS1 variable with
+# the DOCKER_MACHINE_NAME environment variable.
+function __dockermachine_name () {
+    [ -n "$1" ] && eval "$1"
+    PS1=${PS1/\\h/(docker-$DOCKER_MACHINE_NAME)}
+}
+
+function __load_prompt() {
+    # Load the user's bashrc file
+    [ -r "$HOME/.bashrc" ] && . $HOME/.bashrc
+    if [ -n "$PROMPT_COMMAND" ] ; then
+        OLD_PROMPT_COMMAND=$PROMPT_COMMAND
+        PROMPT_COMMAND="__dockermachine_name '$OLD_PROMPT_COMMAND'"
+    else
+        __dockermachine_name
+    fi
+}
+
+if [ -n ${#BASH_LINENO[0]} -a ${BASH_LINENO[0]} -le 0 -a -n "$HISTFILE" ] ; then
+    __load_prompt
+else
+
+    [ -n "$DM_NAME" ] || DM_NAME="dev"
+    if ! docker-machine ls | tail -n +2 | grep -q "^$DM_NAME" ; then
+        echo "Error: $0: Docker-machine named '$DM_NAME' does not exist."
+    else
+        STATUS=$(docker-machine status $DM_NAME)
+        [ "$STATUS" = "Stopped" ] && docker-machine start $DM_NAME
+        eval $(docker-machine env $DM_NAME)
+        _INCLUDING_AS_RC=1
+        exec bash --rcfile ${BASH_SOURCE[0]}
+    fi
+fi