dokku: Problem to set variables for the Dockerfile file

Does the way to set variables for the Dockerfile file still apply for latest version of Dokku? I use Dokku version 0.9.4. I saw the issue https://github.com/dokku/dokku/issues/1860 but I can’t make this approach work, i.e. can’t get the variable into the file…

Here is the command I use:

dokku docker-options:add myapp build '--build-arg "NG_ENV=prod"'

and in my Dockerfile file:

FROM node:6.9.2

ARG NG_ENV

RUN mkdir -p /app

RUN mkdir -p /usr/src/app
WORKDIR /usr/src/app

COPY . /usr/src/app

COPY package.json /usr/src/app/
RUN npm install

RUN $(npm bin)/ng build --aot --environment ${NG_ENV}

EXPOSE 3000

CMD [ "npm", "start" ]

I have nothing in the NG_ENV variable…

Thanks very much for your help!

---

Additional hints

uname -a: Linux prod-myapp 4.4.0-77-generic #98-Ubuntu SMP Wed Apr 26 08:34:02 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux

free -m:

              total        used        free      shared  buff/cache   available
Mem:            992         163         107          10         721         611
Swap:             0           0           0

docker version:

Client:
 Version:      17.05.0-ce
 API version:  1.29
 Go version:   go1.7.5
 Git commit:   89658be
 Built:        Thu May  4 22:10:54 2017
 OS/Arch:      linux/amd64

Server:
 Version:      17.05.0-ce
 API version:  1.29 (minimum version 1.12)
 Go version:   go1.7.5
 Git commit:   89658be
 Built:        Thu May  4 22:10:54 2017
 OS/Arch:      linux/amd64
 Experimental: false

docker -D info:

Containers: 1
 Running: 1
 Paused: 0
 Stopped: 0
Images: 10
Server Version: 17.05.0-ce
Storage Driver: aufs
 Root Dir: /var/lib/docker/aufs
 Backing Filesystem: extfs
 Dirs: 31
 Dirperm1 Supported: true
Logging Driver: json-file
Cgroup Driver: cgroupfs
Plugins: 
 Volume: local
 Network: bridge host macvlan null overlay
Swarm: inactive
Runtimes: runc
Default Runtime: runc
Init Binary: docker-init
containerd version: 9048e5e50717ea4497b757314bad98ea3763c145
runc version: 9c2d8d184e5da67c95d601382adf14862e4f2228
init version: 949e6fa
Security Options:
 apparmor
 seccomp
  Profile: default
Kernel Version: 4.4.0-77-generic
Operating System: Ubuntu 16.04.2 LTS
OSType: linux
Architecture: x86_64
CPUs: 1
Total Memory: 992.4MiB
Name: prod-myapp
ID: MFYU:LFXZ:JRNE:MGZT:L5RC:AYRW:PUQW:O37A:3RUC:L3OK:2CCB:HRZV
Docker Root Dir: /var/lib/docker
Debug Mode (client): true
Debug Mode (server): false
Registry: https://index.docker.io/v1/
Experimental: false
Insecure Registries:
 127.0.0.0/8
Live Restore Enabled: false

sigil -v: 0.4.0

docker run -ti gliderlabs/herokuish:latest herokuish version:

herokuish: 0.3.28
buildpacks:
  heroku-buildpack-multi     v1.0.0
  heroku-buildpack-ruby      v158
  heroku-buildpack-nodejs    v99
  heroku-buildpack-clojure   v76
  heroku-buildpack-python    v99
  heroku-buildpack-java      v51
  heroku-buildpack-gradle    v21
  heroku-buildpack-grails    v21
  heroku-buildpack-scala     v76
  heroku-buildpack-play      v26
  heroku-buildpack-php       v121
  heroku-buildpack-go        v64
  heroku-buildpack-erlang    fa17af9
  buildpack-nginx            v8

dokku version: 0.9.4

---

Output

(with dokku trace on)

-----> Cleaning up...
-----> Building myapp from dockerfile...
-----> Setting config vars
       DOKKU_DOCKERFILE_PORTS: 3000
-----> Setting config vars
       DOKKU_DOCKERFILE_CMD: CMD [ "npm", "start" ]
remote: build context to Docker daemon 835.6 kB
Step 1/11 : FROM node:6.9.2
 ---> faaadb4aaf9b
Step 2/11 : ARG NG_ENV
 ---> Using cache
 ---> bc15c7909c3f
Step 3/11 : RUN mkdir -p /app
 ---> Using cache
 ---> 91a7d779c29c
Step 4/11 : RUN mkdir -p /usr/src/app
 ---> Using cache
 ---> 5fc3f5f03e90
Step 5/11 : WORKDIR /usr/src/app
 ---> Using cache
 ---> 4bb567157a2b
Step 6/11 : COPY . /usr/src/app
 ---> bfee9d3e5980
Removing intermediate container 536fc9df71ab
Step 7/11 : COPY package.json /usr/src/app/
 ---> ca314023f6d5
Removing intermediate container 4dfac19a8a33
Step 8/11 : RUN npm install
 ---> Running in 09b6cec7f4bd

(...)

npm info ok 
 ---> 564b3d9851f9
Removing intermediate container 09b6cec7f4bd
Step 9/11 : RUN $(npm bin)/ng build --aot --environment ${NG_ENV}
 ---> Running in 1e5a1f86c29a
npm info it worked if it ends with ok
npm info using npm@3.10.9
npm info using node@v6.9.2
npm info ok 
Environment "" does not exist.
remote: The command '/bin/sh -c $(npm bin)/ng build --aot --environment ${NG_ENV}' returned a non-zero code: 1
remote: 
To 178.62.215.242:myapp
 ! [remote rejected] develop -> master (pre-receive hook declined)