dokku ps

dokku

@@ -20,7 +20,7 @@ case "$1" in
     ;;
 
   build)
-    APP="$2"; IMAGE="$3"; CACHE_DIR="$HOME/$APP/cache"
+    APP="$2"; IMAGE="$3"; CACHE_DIR="$DOKKU_ROOT/$APP/cache"
     id=$(cat | docker run -i -a stdin progrium/buildstep /bin/bash -c "mkdir -p /app && tar -xC /app")
     test $(docker wait $id) -eq 0
     docker commit $id $IMAGE > /dev/null
@@ -47,18 +47,17 @@ case "$1" in
     APP="$2"; IMAGE="$3"
     pluginhook pre-deploy $APP $IMAGE
 
-    # kill the app when running
-    if [[ -f "$DOKKU_ROOT/$APP/PORT" ]]; then
-      oldid=$(< "$DOKKU_ROOT/$APP/CONTAINER")
-      docker kill $oldid > /dev/null
-    fi
+    dokku ps:deploy $APP
 
-    # start the app
-    id=$(docker run -d -p 5000 -e PORT=5000 $IMAGE /bin/bash -c "/start web")
-    echo $id > "$DOKKU_ROOT/$APP/CONTAINER"
-    port=$(docker port $id 5000 | sed 's/0.0.0.0://')
-    echo $port > "$DOKKU_ROOT/$APP/PORT"
-    echo "http://$(< "$DOKKU_ROOT/HOSTNAME"):$port" > "$DOKKU_ROOT/$APP/URL"
+    # only use web.1 for now...
+    port=$(docker port $APP.web.1 5000 | sed 's/0.0.0.0://') || true
+    if [[ -n "$port" ]]; then
+      echo $port > "$DOKKU_ROOT/$APP/PORT"
+      echo "http://$(< "$DOKKU_ROOT/HOSTNAME"):$port" > "$DOKKU_ROOT/$APP/URL"
+    else
+      echo " !     Failed to get port from $APP.web.1"
+      exit 1
+    fi
 
     pluginhook post-deploy $APP $port
     ;;

plugins/ps/README.md

@@ -0,0 +1,37 @@
+dokku-ps
+========
+
+A process management plugin for [dokku](https://github.com/progrium/dokku).
+
+Modeled after the process/dyno management of heroku.
+
+Written to solve these problems:
+
+1. Restarting crashed containers.
+
+  Because sometimes the process exits because of something like a memory leak and, until we have it fixed, we just want it to keep going.
+
+  And the idea is to use upstart to handle the containers, as described in [dockers host integration docs](http://docs.docker.io/en/latest/use/host_integration/).
+
+2. Being able to start up non `web` processes.
+
+Bonus problems to solve:
+
+1. Monitor & notify.
+
+  I'm guessing since upstart is monitoring the respawning of containers it should be able to notify me by email, irc or something even cooler.
+
+2. Process scaling.
+
+  If we are able to add each process as a backend to the nginx config we should easily be able to load balance the requests over multiple processes. [This PR](https://github.com/progrium/dokku/pull/267) seems like it would help a lot as we would pretty much just generate `$APP_ROOT/nginx.conf` with the processes defined in `$APP_ROOT/PS`. Something like:
+
+    CONF="$APP_ROOT/nginx.conf"
+    echo "upstream $APP {" > $CONF
+    grep "^web=" $APP_ROOT/PS | while read line; do
+      NUM=${line#*=}
+      for ((i=1; i<=$NUM; i++)); do
+        PORT=$(docker port $APP.web.$i 5000 | sed 's/0.0.0.0://')
+        echo "server 127.0.0.1:$PORT;" >> $CONF
+      done
+    done
+    echo "}" >> $CONF

plugins/ps/commands

@@ -0,0 +1,228 @@
+#!/usr/bin/env bash
+set -eo pipefail
+
+#
+# dokku ps
+#
+# ex.
+#
+#   $ dokku ps
+#
+#   === web: `bundle exec thin start -p $PORT`
+#   web.1: up for 5m
+#
+#   === worker: `bundle exec rake jobs`
+#   worker.1: running for 1h
+#
+#
+# dokku ps:scale PROC1=AMOUNT1 [PROC2=AMOUNT2 ...]
+# dokku ps:restart PROC
+# dokku ps:stop PROCS
+#
+
+function ps_list(){
+  APP="$1";
+  APP_ROOT="$DOKKU_ROOT/$APP"
+  APP_PS="$APP_ROOT/PS"
+  echo
+  ps_proc_list $APP | while read i; do
+    NAME=$(cut -d":" -f1 <<< "$i")
+    CMD=$(cut -d":" -f2 <<< "$i")
+    echo "=== $NAME: \`${CMD/ /}\`"
+    grep "^$NAME=" $APP_PS | while read line; do
+      NUM=${line#*=}
+      for ((i=1; i<=$NUM; i++)); do
+        ps_status $APP $NAME $i
+      done
+    done
+  done
+  echo
+}
+
+function ps_scale(){
+  APP="$1"; shift; PAIRS="$@";
+  APP_ROOT="$DOKKU_ROOT/$APP"
+  APP_PS="$APP_ROOT/PS"
+
+  # convert the arguments into an array
+  pairs=( $PAIRS )
+
+  # store the current list of processes
+  PS=$(cat $APP_PS)
+
+  # reset PS
+  # TODO use temp file instead and then `mv` should be safer
+  echo -n > $APP_PS
+
+  # get the list of available procs (according to Procfile)
+  ps_proc_list $APP | while read i; do
+    NAME=$(cut -d":" -f1 <<< "$i")
+
+    # a variable to check if it was found
+    found=""
+
+    # see if $NAME is found among the $PAIRS
+    for line in ${PAIRS[@]}; do
+      name=${line%%=*}
+      to=${line#*=}
+
+      # found it
+      if [ "$name" = "$NAME" ]; then
+        # verify that $to is a number
+        if [ $to -ge 0 2>/dev/null ]; then
+          found=1
+          echo "$name=$to" >> $APP_PS
+        else
+          echo " Skipping \"$name\". \"$to\" is not an integer."
+        fi
+      fi
+    done
+
+    # in case it wasn't an argument use the current one
+    if [ -z "$found" ]; then
+      grep "^$NAME=" <<< $PS >> $APP_PS
+    fi
+  done
+
+  # output the final PS
+  cat $APP_PS
+
+  # now deploy!
+  ps_deploy $APP
+}
+
+function ps_deploy(){
+  APP="$1"; IMAGE="app/$APP"
+  APP_ROOT="$DOKKU_ROOT/$APP"
+  APP_PS="$APP_ROOT/PS"
+
+  cat $APP_PS | while read line; do
+    NAME=${line%%=*}
+    NUM=${line#*=}
+
+    # stop any running processes first otherwise
+    # `docker kill` will just make it restart
+    ps_each stop $APP $NAME $NUM || true
+
+    for ((i=1; i<=$NUM; i++)); do
+      # remove container if already exists
+      # outputs the id if existed, nothing otherwise
+      docker kill "$APP.$NAME.$i" > /dev/null
+      docker rm "$APP.$NAME.$i" > /dev/null
+
+      # create a named container using `docker run`
+      id=$(docker run -d -name "$APP.$NAME.$i" -p 5000 -e PORT=5000 $IMAGE /start $NAME)
+
+      # TODO make sure it started?
+
+      # stop the container again (to be started using upstart instead)
+      docker stop $id > /dev/null # outputs the id if existed, nothing otherwise
+    done
+    echo "-----> Starting $NAME"
+    ps_each start $APP $NAME $NUM
+    echo "       $NUM processes up and running"
+    sleep 5
+  done
+}
+
+function ps_stop(){
+  APP="$1"; NAME="$2";
+  APP_ROOT="$DOKKU_ROOT/$APP"
+  APP_PS="$APP_ROOT/PS"
+
+  # require name
+  if [ -z "$NAME" ]; then
+    echo "Missing PROC for \"$APP\""
+    exit 1
+  fi
+
+  grep "^$NAME=" $APP_PS | while read line; do
+    ps_each stop $APP ${line%%=*} ${line#*=}
+  done
+}
+
+function ps_status(){
+  APP="$1"; NAME="$2"; SEQ="$3";
+  # formatting is based on
+  # https://github.com/dotcloud/docker/blob/b038b0cd44e152fa4158f2bfe145de6d774dd8d0/state.go#L20
+  STATUS=$(docker ps -a | grep "$APP.$NAME.$SEQ" | grep -Eo '(Up [0-9]+ [a-z]+|Ghost|Exit [0-9]+)')
+  echo "$NAME.$SEQ: $STATUS"
+}
+
+function ps_restart(){
+  APP="$1"; NAME="$2";
+  APP_ROOT="$DOKKU_ROOT/$APP"
+  APP_PS="$APP_ROOT/PS"
+
+  # default to all procs
+  if [ -z "$NAME" ]; then
+    NAME=$(ps_proc_list $APP | cut -d":" -f1) || {
+      echo "App \"$APP\" has no processes to restart" >&2
+      exit 1
+    }
+  fi
+
+  grep "^$NAME=" $APP_PS | while read line; do
+    ps_each restart $APP ${line%%=*} ${line#*=}
+  done
+}
+
+function ps_each(){
+  CMD="$1"; APP="$2"; NAME="$3"; NUM="$4"
+  for ((i=1; i<=$NUM; i++)); do
+    sudo $CMD dokku-ps APP=$APP NAME=$NAME SEQ=$i || {
+      # echo " -- failed with exit $? --"
+      true # don't skip the rest if one was already stopped/started
+    }
+    sleep 1
+  done
+}
+
+function ps_proc_list(){
+  APP="$1"; IMAGE="app/$APP"
+  # TODO this should probably be something defined in /app/.release
+  # so it doesn't have to fire up a container every time?
+  docker run -rm $IMAGE cat /app/Procfile
+}
+
+function ps_usage(){
+  cat<<EOF
+    ps <app>                                        List processes for an app
+    ps:restart <app> [PROC]                         Restart an app process
+    ps:scale <app> PROC1=NUM1 [PROC2=NUM2...]       Scale processes by the given amount
+    ps:stop <app> PROC                              Stop an app process
+
+EOF
+}
+
+# Check if name is specified
+if [[ $1 == ps ]] || [[ $1 == ps:* ]]; then
+  if [[ -z $2 ]]; then
+    echo "You must specify an app name"
+    exit 1
+  else
+    APP="$2"
+    PS_FILE="$DOKKU_ROOT/$APP/PS"
+
+    # Check if app exists with the same name
+    if [ ! -d "$DOKKU_ROOT/$APP" ]; then
+      echo "App $APP does not exist"
+      exit 1
+    fi
+
+    # Check if app has a PS file
+    if [ ! -f "$PS_FILE" ]; then
+      echo "web=1" > $PS_FILE
+    fi
+  fi
+fi
+
+case "$1" in
+  ps) ps_list $APP; exit ;;
+  ps:scale) shift 2; ps_scale $APP "$@"; exit ;;
+  ps:restart) shift 2; ps_restart $APP $1; exit ;;
+  ps:stop) shift 2; ps_stop $APP $1; exit ;;
+  ps:deploy) ps_deploy $APP; exit ;; # internal
+  help) ps_usage ;;
+esac
+cat

plugins/ps/install

@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+set -eo pipefail
+
+sed -i 's/docker -d -r=true$/docker -d -r=false/' /etc/init/docker.conf
+
+cat<<EOF > /etc/sudoers.d/dokku-ps
+%dokku ALL=(ALL)NOPASSWD:/sbin/start dokku-ps *
+%dokku ALL=(ALL)NOPASSWD:/sbin/restart dokku-ps *
+%dokku ALL=(ALL)NOPASSWD:/sbin/stop dokku-ps *
+EOF
+
+cat<<EOF > /etc/init/dokku-ps.conf
+instance \$APP.\$NAME.\$SEQ
+description "Dokku PS \$APP.\$NAME.\$SEQ"
+author "Dokku PS"
+start on filesystem and started lxc-net and started docker
+stop on runlevel [!2345]
+respawn
+respawn limit 10 5
+kill signal KILL
+exec /usr/bin/docker start -a "\$APP.\$NAME.\$SEQ"
+post-stop exec /usr/bin/docker kill "\$APP.\$NAME.\$SEQ"
+EOF

tests/test_deploy

@@ -13,7 +13,7 @@ git commit -m 'initial commit'
 REPO="test-$(basename $APP)-$RANDOM"
 git remote add target dokku@$TARGET:$REPO
 git push target master
-URL=$(ssh dokku@$TARGET url $REPO)$FORWARDED_PORT
+URL=$(echo | ssh dokku@$TARGET url $REPO)$FORWARDED_PORT
 sleep 2
 ./check_deploy $URL && echo "-----> Deploy success!" || {
   sleep 4