Merge pull request #128 from nuex/dtl_scripts

Make scripts in rlx_prv_assembler DTL templates

7 files changed, 620 insertions, 0 deletions

diff --git a/priv/templates/bin.dtl b/priv/templates/bin.dtl
new file mode 100644
index 0000000..067e9f7
--- /dev/null
+++ b/priv/templates/bin.dtl
@@ -0,0 +1,44 @@
+#!/bin/sh
+
+set -e
+
+SCRIPT_DIR=`dirname $0`
+RELEASE_ROOT_DIR=`cd $SCRIPT_DIR/.. && pwd`
+REL_NAME={{ rel_name }}
+REL_VSN={{ rel_vsn }}
+ERTS_VSN={{ erts_vsn }}
+REL_DIR=$RELEASE_ROOT_DIR/releases/$REL_VSN
+ERL_OPTS={{ erl_opts }}
+
+find_erts_dir() {
+    local erts_dir=$RELEASE_ROOT_DIR/erts-$ERTS_VSN
+    if [ -d "$erts_dir" ]; then
+        ERTS_DIR=$erts_dir;
+        ROOTDIR=$RELEASE_ROOT_DIR
+    else
+        local erl=`which erl`
+        local erl_root=`$erl -noshell -eval "io:format(\\"~s\\", [code:root_dir()])." -s init stop`
+        ERTS_DIR=$erl_root/erts-$ERTS_VSN
+        ROOTDIR=$erl_root
+    fi
+
+}
+
+find_sys_config() {
+    local possible_sys=$REL_DIR/sys.config
+    if [ -f "$possible_sys" ]; then
+        SYS_CONFIG="-config $possible_sys"
+    fi
+}
+
+find_erts_dir
+find_sys_config
+export ROOTDIR=$RELEASE_ROOT_DIR
+export BINDIR=$ERTS_DIR/bin
+export EMU=beam
+export PROGNAME=erl
+export LD_LIBRARY_PATH=$ERTS_DIR/lib:$LD_LIBRARY_PATH
+
+cd $ROOTDIR
+
+$BINDIR/erlexec $ERL_OPTS $SYS_CONFIG -boot $REL_DIR/$REL_NAME $@
diff --git a/priv/templates/erl_script.dtl b/priv/templates/erl_script.dtl
new file mode 100644
index 0000000..72e93dd
--- /dev/null
+++ b/priv/templates/erl_script.dtl
@@ -0,0 +1,13 @@
+#!/bin/sh
+set -e
+
+SCRIPT_DIR=`dirname $0`
+ROOTDIR=`cd $SCRIPT_DIR/../../ && pwd`
+BINDIR=$ROOTDIR/erts-{{ erts_vsn }}/bin
+EMU=beam
+PROGNAME=`echo $0 | sed 's/.*\\///'`
+export EMU
+export ROOTDIR
+export BINDIR
+export PROGNAME
+exec "$BINDIR/erlexec" ${1+"$@"}
diff --git a/priv/templates/extended_bin.dtl b/priv/templates/extended_bin.dtl
new file mode 100644
index 0000000..a0e46a9
--- /dev/null
+++ b/priv/templates/extended_bin.dtl
@@ -0,0 +1,292 @@
+#!/bin/sh
+
+set -e
+
+SCRIPT_DIR=`dirname $0`
+RELEASE_ROOT_DIR=`cd $SCRIPT_DIR/.. && pwd`
+REL_NAME={{ rel_name }}
+REL_VSN={{ rel_vsn }}
+ERTS_VSN={{ erts_vsn }}
+REL_DIR=$RELEASE_ROOT_DIR/releases/$REL_VSN
+ERL_OPTS={{ erl_opts }}
+PIPE_DIR=/tmp/erl_pipes/{{ rel_name }}/
+
+find_erts_dir() {
+    local erts_dir=$RELEASE_ROOT_DIR/erts-$ERTS_VSN
+    if [ -d "$erts_dir" ]; then
+        ERTS_DIR=$erts_dir;
+        ROOTDIR=$RELEASE_ROOT_DIR
+    else
+        local erl=`which erl`
+        local erl_root=`$erl -noshell -eval "io:format(\\"~s\\", [code:root_dir()])." -s init stop`
+        ERTS_DIR=$erl_root/erts-$ERTS_VSN
+        ROOTDIR=$erl_root
+    fi
+
+}
+
+find_sys_config() {
+    local possible_sys=$REL_DIR/sys.config
+    if [ -f "$possible_sys" ]; then
+        SYS_CONFIG="-config $possible_sys"
+    fi
+}
+
+# Use $CWD/vm.args if exists, otherwise releases/APP_VSN/vm.args, or else etc/vm.args
+if [ -e "$RELEASE_ROOT_DIR/vm.args" ]; then
+    VMARGS_PATH=$RELEASE_ROOT_DIR/vm.args
+    USE_DIR=$RELEASE_ROOT_DIR
+else
+    USE_DIR=$REL_DIR
+    if [ -e "$REL_DIR/vm.args" ]; then
+        VMARGS_PATH="$REL_DIR/vm.args"
+    else
+        VMARGS_PATH="$REL_DIR/vm.args"
+    fi
+fi
+
+RUNNER_LOG_DIR=$RELEASE_ROOT_DIR/log
+# Make sure log directory exists
+mkdir -p $RUNNER_LOG_DIR
+
+# Use releases/VSN/sys.config if it exists otherwise use etc/app.config
+if [ -e "$USE_DIR/sys.config" ]; then
+    CONFIG_PATH="$USE_DIR/sys.config"
+else
+    if [ -e "$REL_DIR/sys.config" ]; then
+        CONFIG_PATH="$REL_DIR/sys.config"
+    else
+        CONFIG_PATH="$REL_DIR/app.config"
+    fi
+fi
+
+# Extract the target node name from node.args
+NAME_ARG=`egrep '^-s?name' $VMARGS_PATH`
+if [ -z "$NAME_ARG" ]; then
+    echo "vm.args needs to have either -name or -sname parameter."
+    exit 1
+fi
+
+# Extract the name type and name from the NAME_ARG for REMSH
+REMSH_TYPE=`echo $NAME_ARG | awk '{print $1}'`
+REMSH_NAME=`echo $NAME_ARG | awk '{print $2}'`
+
+# Note the `date +%s`, used to allow multiple remsh to the same node transparently
+REMSH_NAME_ARG="$REMSH_TYPE remsh`date +%s`@`echo $REMSH_NAME | awk -F@ '{print $2}'`"
+REMSH_REMSH_ARG="-remsh $REMSH_NAME -boot start_clean"
+
+# Extract the target cookie
+COOKIE_ARG=`grep '^-setcookie' $VMARGS_PATH`
+if [ -z "$COOKIE_ARG" ]; then
+    echo "vm.args needs to have a -setcookie parameter."
+    exit 1
+fi
+
+find_erts_dir
+find_sys_config
+export ROOTDIR=$RELEASE_ROOT_DIR
+export BINDIR=$ERTS_DIR/bin
+export EMU=beam
+export PROGNAME=erl
+export LD_LIBRARY_PATH=$ERTS_DIR/lib:$LD_LIBRARY_PATH
+
+cd $ROOTDIR
+
+# Setup remote shell command to control node
+REMSH="$BINDIR/erl $REMSH_NAME_ARG $REMSH_REMSH_ARG $COOKIE_ARG"
+
+# Setup command to control the node
+NODETOOL="$BINDIR/escript $ROOTDIR/bin/nodetool $NAME_ARG $COOKIE_ARG"
+
+# Check the first argument for instructions
+case "$1" in
+    start|start_boot)
+
+        # Make sure there is not already a node running
+        #RES=`$NODETOOL ping`
+        #if [ "$RES" = "pong" ]; then
+        #    echo "Node is already running!"
+        #    exit 1
+        #fi
+        case "$1" in
+            start)
+                shift
+                START_OPTION="console"
+                HEART_OPTION="start"
+                ;;
+            start_boot)
+                shift
+                START_OPTION="console_boot"
+                HEART_OPTION="start_boot"
+                ;;
+        esac
+        RUN_PARAM=$(printf "'%s' " "$@")
+        HEART_COMMAND="$SCRIPT_DIR/bin/$REL_NAME $HEART_OPTION $RUN_PARAM"
+        export HEART_COMMAND
+        mkdir -p $PIPE_DIR
+        $BINDIR/run_erl -daemon $PIPE_DIR $RUNNER_LOG_DIR "exec $RELEASE_ROOT_DIR/bin/$REL_NAME $START_OPTION $RUN_PARAM" 2>&1
+        ;;
+
+    stop)
+        # Wait for the node to completely stop...
+        case `uname -s` in
+            Linux|Darwin|FreeBSD|DragonFly|NetBSD|OpenBSD)
+                # PID COMMAND
+                PID=`ps ax -o pid= -o command=|
+                    grep "$SCRIPT_DIR/.*/[b]eam"|awk '{print $1}'`
+                ;;
+            SunOS)
+                # PID COMMAND
+                PID=`ps -ef -o pid= -o args=|
+                    grep "$SCRIPT_DIR/.*/[b]eam"|awk '{print $1}'`
+                ;;
+            CYGWIN*)
+                # UID PID PPID TTY STIME COMMAND
+                PID=`ps -efW|grep "$SCRIPT_DIR/.*/[b]eam"|awk '{print $2}'`
+                ;;
+        esac
+        $NODETOOL stop
+        ES=$?
+        if [ "$ES" -ne 0 ]; then
+            exit $ES
+        fi
+        while `kill -0 $PID 2>/dev/null`;
+        do
+            sleep 1
+        done
+        ;;
+
+    restart)
+        ## Restart the VM without exiting the process
+        $NODETOOL restart
+        ES=$?
+        if [ "$ES" -ne 0 ]; then
+            exit $ES
+        fi
+        ;;
+
+    reboot)
+        ## Restart the VM completely (uses heart to restart it)
+        $NODETOOL reboot
+        ES=$?
+        if [ "$ES" -ne 0 ]; then
+            exit $ES
+        fi
+        ;;
+
+    ping)
+        ## See if the VM is alive
+        $NODETOOL ping
+        ES=$?
+        if [ "$ES" -ne 0 ]; then
+            exit $ES
+        fi
+        ;;
+
+    attach)
+        # Make sure a node IS running
+        RES=`$NODETOOL ping`
+        ES=$?
+        if [ "$ES" -ne 0 ]; then
+            echo "Node is not running!"
+            exit $ES
+        fi
+
+        shift
+        exec $BINDIR/to_erl $PIPE_DIR
+        ;;
+
+    remote_console)
+        # Make sure a node IS running
+        RES=`$NODETOOL ping`
+        ES=$?
+        if [ "$ES" -ne 0 ]; then
+            echo "Node is not running!"
+            exit $ES
+        fi
+
+        shift
+        exec $REMSH
+        ;;
+
+    upgrade|downgrade|install)
+        if [ -z "$2" ]; then
+            echo "Missing package argument"
+            echo "Usage: $REL_NAME $1 {package base name}"
+            echo "NOTE {package base name} MUST NOT include the .tar.gz suffix"
+            exit 1
+        fi
+
+        # Make sure a node IS running
+        RES=`$NODETOOL ping`
+        ES=$?
+        if [ "$ES" -ne 0 ]; then
+            echo "Node is not running!"
+            exit $ES
+        fi
+
+        node_name=`echo $NAME_ARG | awk '{print $2}'`
+        erlang_cookie=`echo $COOKIE_ARG | awk '{print $2}'`
+
+        exec $BINDIR/escript $ROOTDIR/bin/install_upgrade.escript $REL_NAME $node_name $erlang_cookie $2
+        ;;
+
+    console|console_clean|console_boot)
+        # .boot file typically just $REL_NAME (ie, the app name)
+        # however, for debugging, sometimes start_clean.boot is useful.
+        # For e.g. 'setup', one may even want to name another boot script.
+        case "$1" in
+            console)        [ -f $REL_DIR/$REL_NAME.boot ] && BOOTFILE=$REL_DIR/$REL_NAME || BOOTFILE=$REL_DIR/start ;;
+            console_clean)  BOOTFILE=$ROOTDIR/bin/start_clean ;;
+            console_boot)
+                shift
+                BOOTFILE="$1"
+                shift
+                ;;
+        esac
+        # Setup beam-required vars
+        EMU=beam
+        PROGNAME=`echo $0 | sed 's/.*\\///'`
+        CMD="$BINDIR/erlexec -boot $BOOTFILE -env ERL_LIBS $REL_DIR/lib -config $CONFIG_PATH -args_file $VMARGS_PATH"
+        export EMU
+        export PROGNAME
+
+        # Dump environment info for logging purposes
+        echo "Exec: $CMD" -- ${1+"$@"}
+        echo "Root: $ROOTDIR"
+
+        # Log the startup
+        logger -t "$REL_NAME[$$]" "Starting up"
+
+        # Start the VM
+        exec $CMD -- ${1+"$@"}
+        ;;
+
+    foreground)
+        # start up the release in the foreground for use by runit
+        # or other supervision services
+
+        [ -f $REL_DIR/$REL_NAME.boot ] && BOOTFILE=$REL_NAME || BOOTFILE=start
+        FOREGROUNDOPTIONS="-noinput +Bd"
+
+        # Setup beam-required vars
+        EMU=beam
+        PROGNAME=`echo $0 | sed 's/.*\\///'`
+        CMD="$BINDIR/erlexec $FOREGROUNDOPTIONS -boot $REL_DIR/$BOOTFILE -mode embedded -config $CONFIG_PATH -args_file $VMARGS_PATH"
+        export EMU
+        export PROGNAME
+
+        # Dump environment info for logging purposes
+        echo "Exec: $CMD" -- ${1+"$@"}
+        echo "Root: $ROOTDIR"
+
+        # Start the VM
+        exec $CMD -- ${1+"$@"}
+        ;;
+    *)
+        echo "Usage: $REL_NAME {start|start_boot <file>|foreground|stop|restart|reboot|ping|console|console_clean|console_boot <file>|attach|remote_console|upgrade}"
+        exit 1
+        ;;
+esac
+
+exit 0
diff --git a/priv/templates/install_upgrade_escript.dtl b/priv/templates/install_upgrade_escript.dtl
new file mode 100644
index 0000000..7c331aa
--- /dev/null
+++ b/priv/templates/install_upgrade_escript.dtl
@@ -0,0 +1,106 @@
+#!/usr/bin/env escript
+%%! -noshell -noinput
+%% -*- mode: erlang;erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ft=erlang ts=4 sw=4 et
+
+-define(TIMEOUT, 60000).
+-define(INFO(Fmt,Args), io:format(Fmt,Args)).
+
+%% Upgrades, to a new tar.gz release
+main([RelName, NodeName, Cookie, VersionArg]) ->
+    TargetNode = start_distribution(NodeName, Cookie),
+    WhichReleases = which_releases(TargetNode),
+    Version = parse_version(VersionArg),
+    case proplists:get_value(Version, WhichReleases) of
+        undefined ->
+            %% not installed, so unpack tarball:
+            ?INFO("Release ~s not found, attempting to unpack releases/~s/~s.tar.gz~n",[Version,Version,RelName]),
+            ReleasePackage = Version ++ "/" ++ RelName,
+            case rpc:call(TargetNode, release_handler, unpack_release,
+                          [ReleasePackage], ?TIMEOUT) of
+                {ok, Vsn} ->
+                    ?INFO("Unpacked successfully: ~p~n", [Vsn]),
+                    install_and_permafy(TargetNode, RelName, Vsn);
+                {error, UnpackReason} ->
+                    print_existing_versions(TargetNode),
+                    ?INFO("Unpack failed: ~p~n",[UnpackReason]),
+                    erlang:halt(2)
+            end;
+        old ->
+            %% no need to unpack, has been installed previously
+            ?INFO("Release ~s is marked old, switching to it.~n",[Version]),
+            install_and_permafy(TargetNode, RelName, Version);
+        unpacked ->
+            ?INFO("Release ~s is already unpacked, now installing.~n",[Version]),
+            install_and_permafy(TargetNode, RelName, Version);
+        current -> %% installed and in-use, just needs to be permanent
+            ?INFO("Release ~s is already installed and current. Making permanent.~n",[Version]),
+            permafy(TargetNode, RelName, Version);
+        permanent ->
+            ?INFO("Release ~s is already installed, and set permanent.~n",[Version])
+    end;
+main(_) ->
+    erlang:halt(1).
+
+parse_version(V) when is_list(V) ->
+    hd(string:tokens(V,"/")).
+
+install_and_permafy(TargetNode, RelName, Vsn) ->
+    case rpc:call(TargetNode, release_handler, check_install_release, [Vsn], ?TIMEOUT) of
+        {ok, _OtherVsn, _Desc} ->
+            ok;
+        {error, Reason} ->
+            ?INFO("ERROR: release_handler:check_install_release failed: ~p~n",[Reason]),
+            erlang:halt(3)
+    end,
+    case rpc:call(TargetNode, release_handler, install_release, [Vsn], ?TIMEOUT) of
+        {ok, _, _} ->
+            ?INFO("Installed Release: ~s~n", [Vsn]),
+            permafy(TargetNode, RelName, Vsn),
+            ok;
+        {error, {no_such_release, Vsn}} ->
+            VerList =
+                iolist_to_binary(
+                    [io_lib:format("* ~s\t~s~n",[V,S]) ||  {V,S} <- which_releases(TargetNode)]),
+            ?INFO("Installed versions:~n~s", [VerList]),
+            ?INFO("ERROR: Unable to revert to '~s' - not installed.~n", [Vsn]),
+            erlang:halt(2)
+    end.
+
+permafy(TargetNode, RelName, Vsn) ->
+    ok = rpc:call(TargetNode, release_handler, make_permanent, [Vsn], ?TIMEOUT),
+    file:copy(filename:join(["bin", RelName++"-"++Vsn]),
+              filename:join(["bin", RelName])),
+    ?INFO("Made release permanent: ~p~n", [Vsn]),
+    ok.
+
+which_releases(TargetNode) ->
+    R = rpc:call(TargetNode, release_handler, which_releases, [], ?TIMEOUT),
+    [ {V, S} ||  {_,V,_, S} <- R ].
+
+print_existing_versions(TargetNode) ->
+    VerList = iolist_to_binary([
+            io_lib:format("* ~s\t~s~n",[V,S])
+            ||  {V,S} <- which_releases(TargetNode) ]),
+    ?INFO("Installed versions:~n~s", [VerList]).
+
+start_distribution(NodeName, Cookie) ->
+    MyNode = make_script_node(NodeName),
+    {ok, _Pid} = net_kernel:start([MyNode, longnames]),
+    erlang:set_cookie(node(), list_to_atom(Cookie)),
+    TargetNode = list_to_atom(NodeName),
+    case {net_kernel:connect_node(TargetNode),
+          net_adm:ping(TargetNode)} of
+        {true, pong} ->
+            ok;
+        {_, pang} ->
+            io:format("Node ~p not responding to pings.\n", [TargetNode]),
+            erlang:halt(1)
+    end,
+    {ok, Cwd} = file:get_cwd(),
+    ok = rpc:call(TargetNode, file, set_cwd, [Cwd], ?TIMEOUT),
+    TargetNode.
+
+make_script_node(Node) ->
+    [Name, Host] = string:tokens(Node, "@"),
+    list_to_atom(lists:concat([Name, "_upgrader_", os:getpid(), "@", Host])).
diff --git a/priv/templates/nodetool.dtl b/priv/templates/nodetool.dtl
new file mode 100644
index 0000000..a6faad5
--- /dev/null
+++ b/priv/templates/nodetool.dtl
@@ -0,0 +1,137 @@
+%% -*- mode: erlang;erlang-indent-level: 4;indent-tabs-mode: nil -*-
+%% ex: ft=erlang ts=4 sw=4 et
+%% -------------------------------------------------------------------
+%%
+%% nodetool: Helper Script for interacting with live nodes
+%%
+%% -------------------------------------------------------------------
+
+main(Args) ->
+    ok = start_epmd(),
+    %% Extract the args
+    {RestArgs, TargetNode} = process_args(Args, [], undefined),
+
+    %% See if the node is currently running  -- if it's not, we'll bail
+    case {net_kernel:hidden_connect_node(TargetNode), net_adm:ping(TargetNode)} of
+        {true, pong} ->
+            ok;
+        {_, pang} ->
+            io:format("Node ~p not responding to pings.\n", [TargetNode]),
+            halt(1)
+    end,
+
+    case RestArgs of
+        ["ping"] ->
+            %% If we got this far, the node already responsed to a ping, so just dump
+            %% a "pong"
+            io:format("pong\n");
+        ["stop"] ->
+            io:format("~p\n", [rpc:call(TargetNode, init, stop, [], 60000)]);
+        ["restart"] ->
+            io:format("~p\n", [rpc:call(TargetNode, init, restart, [], 60000)]);
+        ["reboot"] ->
+            io:format("~p\n", [rpc:call(TargetNode, init, reboot, [], 60000)]);
+        ["rpc", Module, Function | RpcArgs] ->
+            case rpc:call(TargetNode, list_to_atom(Module), list_to_atom(Function),
+                          [RpcArgs], 60000) of
+                ok ->
+                    ok;
+                {badrpc, Reason} ->
+                    io:format("RPC to ~p failed: ~p\n", [TargetNode, Reason]),
+                    halt(1);
+                _ ->
+                    halt(1)
+            end;
+        ["rpcterms", Module, Function, ArgsAsString] ->
+            case rpc:call(TargetNode, list_to_atom(Module), list_to_atom(Function),
+                          consult(ArgsAsString), 60000) of
+                {badrpc, Reason} ->
+                    io:format("RPC to ~p failed: ~p\n", [TargetNode, Reason]),
+                    halt(1);
+                Other ->
+                    io:format("~p\n", [Other])
+            end;
+        Other ->
+            io:format("Other: ~p\n", [Other]),
+            io:format("Usage: nodetool {ping|stop|restart|reboot}\n")
+    end,
+    net_kernel:stop().
+
+process_args([], Acc, TargetNode) ->
+    {lists:reverse(Acc), TargetNode};
+process_args(["-setcookie", Cookie | Rest], Acc, TargetNode) ->
+    erlang:set_cookie(node(), list_to_atom(Cookie)),
+    process_args(Rest, Acc, TargetNode);
+process_args(["-name", TargetName | Rest], Acc, _) ->
+    ThisNode = append_node_suffix(TargetName, "_maint_"),
+    {ok, _} = net_kernel:start([ThisNode, longnames]),
+    process_args(Rest, Acc, nodename(TargetName));
+process_args(["-sname", TargetName | Rest], Acc, _) ->
+    ThisNode = append_node_suffix(TargetName, "_maint_"),
+    {ok, _} = net_kernel:start([ThisNode, shortnames]),
+    process_args(Rest, Acc, nodename(TargetName));
+process_args([Arg | Rest], Acc, Opts) ->
+    process_args(Rest, [Arg | Acc], Opts).
+
+
+start_epmd() ->
+    [] = os:cmd(epmd_path() ++ " -daemon"),
+    ok.
+
+epmd_path() ->
+    ErtsBinDir = filename:dirname(escript:script_name()),
+    Name = "epmd",
+    case os:find_executable(Name, ErtsBinDir) of
+        false ->
+            case os:find_executable(Name) of
+                false ->
+                    io:format("Could not find epmd.~n"),
+                    halt(1);
+                GlobalEpmd ->
+                    GlobalEpmd
+            end;
+        Epmd ->
+            Epmd
+    end.
+
+
+nodename(Name) ->
+    case string:tokens(Name, "@") of
+        [_Node, _Host] ->
+            list_to_atom(Name);
+        [Node] ->
+            [_, Host] = string:tokens(atom_to_list(node()), "@"),
+            list_to_atom(lists:concat([Node, "@", Host]))
+    end.
+
+append_node_suffix(Name, Suffix) ->
+    case string:tokens(Name, "@") of
+        [Node, Host] ->
+            list_to_atom(lists:concat([Node, Suffix, os:getpid(), "@", Host]));
+        [Node] ->
+            list_to_atom(lists:concat([Node, Suffix, os:getpid()]))
+    end.
+
+%%
+%% Given a string or binary, parse it into a list of terms, ala file:consult/0
+%%
+consult(Str) when is_list(Str) ->
+    consult([], Str, []);
+consult(Bin) when is_binary(Bin)->
+    consult([], binary_to_list(Bin), []).
+
+consult(Cont, Str, Acc) ->
+    case erl_scan:tokens(Cont, Str, 0) of
+        {done, Result, Remaining} ->
+            case Result of
+                {ok, Tokens, _} ->
+                    {ok, Term} = erl_parse:parse_term(Tokens),
+                    consult([], Remaining, [Term | Acc]);
+                {eof, _Other} ->
+                    lists:reverse(Acc);
+                {error, Info, _} ->
+                    {error, Info}
+            end;
+        {more, Cont1} ->
+            consult(Cont1, eof, Acc)
+    end.
diff --git a/priv/templates/sys_config.dtl b/priv/templates/sys_config.dtl
new file mode 100644
index 0000000..eda2e75
--- /dev/null
+++ b/priv/templates/sys_config.dtl
@@ -0,0 +1,9 @@
+%% Thanks to Ulf Wiger at Ericcson for these comments:
+%%
+%% This file is identified via the erl command line option -config File.
+%% Note that File should have no extension, e.g.
+%% erl -config .../sys (if this file is called sys.config)
+%%
+%% In this file, you can redefine application environment variables.
+%% This way, you don't have to modify the .app files of e.g. OTP applications.
+[].
diff --git a/priv/templates/vm_args.dtl b/priv/templates/vm_args.dtl
new file mode 100644
index 0000000..558ce39
--- /dev/null
+++ b/priv/templates/vm_args.dtl
@@ -0,0 +1,19 @@
+## Name of the node
+-name {{ rel_name }}@127.0.0.1
+
+## Cookie for distributed erlang
+-setcookie {{ rel_name }}
+
+## Heartbeat management; auto-restarts VM if it dies or becomes unresponsive
+## (Disabled by default..use with caution!)
+##-heart
+
+## Enable kernel poll and a few async threads
+##+K true
+##+A 5
+
+## Increase number of concurrent ports/sockets
+##-env ERL_MAX_PORTS 4096
+
+## Tweak GC to run more often
+##-env ERL_FULLSWEEP_AFTER 10