Configure web front-end via command line interface

[psyhtest]

I'm working on building Docker images containing CK and its dependencies.

A snapshot of my Dockerfile based on Ubuntu 16.04 is as follows:

FROM ubuntu:16.04
MAINTAINER Anton Lokhmotov

# Install standard packages.
RUN apt-get update && apt-get install -y \
    python-all \
    git

# Install the core Collective Knowledge (CK) module.
ENV CK_ROOT=$HOME/CK/ck CK_TOOLS=$HOME/CK_TOOLS PATH=$CK_ROOT/bin:$PATH

RUN mkdir -p $HOME/CK && git clone https://github.com/ctuning/ck.git $CK_ROOT
RUN mkdir -p $HOME/CK_TOOLS

RUN cd $CK_ROOT && python setup.py install && python -c "import ck.kernel as ck"

# Install other CK modules.
RUN ck pull repo:ck-web

# Listen on the standard CK port.
CK_PORT=3344
EXPOSE $CK_PORT

# Start the web service.
CMD ck start web --host=`hostname -i` --port=${CK_PORT}

To build an image named ctuning/ck-ubuntu-16.04, run:

$ docker build -t ctuning/ck-ubuntu-16.04 ${DOCKERFILE_DIR}

where ${DOCKERFILE_DIR} is the directory containing the above Dockerfile (e.g. ${CK_DOCKER_DIR}/docker/ubuntu-16.04).

The CK web service can be accessed at http://localhost:3344/ by running the image in a container as follows:

$ docker run --rm -it -p 3344:3344 ctuning/ck-ubuntu-16.04
For now we can only start server indefinitely
but we should add a proper start/stop/resume support at some point ...

Starting CK web service on 172.17.0.2:3344 ...

or at http://localhost:3355/ with a more elaborate command:

$ export WFE_PORT=3355 CK_PORT=3366
$ docker run --rm -it -p ${WFE_PORT}:${CK_PORT} --env CK_PORT=${CK_PORT} \
    ctuning/ck-ubuntu-16.04
For now we can only start server indefinitely
but we should add a proper start/stop/resume support at some point ...

Starting CK web service on 172.17.0.2:3366 ...

That is, the CK web service is running inside the container with --host=hostname -i`` and --port=${CK_PORT}, and can be accessed at `http://localhost:${WFE_PORT}`. So far so good.

Now, suppose I want to access the CK web service running inside a Docker container on http://${WFE_HOST}:${WFE_PORT}. I have port forwarding enabled from ${WFE_PORT} to the ${WFE_HOST} machine where the container is running. Here's what I have to do currently:

$ docker run --rm -it -p ${WFE_PORT}:${CK_PORT} --env CK_PORT=${CK_PORT} \
    ctuning/ck-ubuntu-16.04 /bin/bash
root@cc8a1ff17ae9:/# ck setup kernel --wfe
=======================================================================
Loading current configuration ...
=======================================================================
*** Web front end control (through CK web server or third-party web server and CK php connector) ***

Current web front-end URL prefix: http://localhost:3344/web?
Current web front-end template:   default

Enter new web front-end URL prefix (Enter to keep previous): http://<WFE_HOST>:<WFE_PORT>/web?
Enter new web front-end template (Enter to keep previous): 
=======================================================================
Writing local configuration (directly) ...

Configuration successfully recorded to /root/CK/local/kernel/default/.cm/meta.json ...
root@cc8a1ff17ae9:/# ck start web --host=`hostname -i` --port=${CK_PORT} --use_wfe_url
For now we can only start server indefinitely
but we should add a proper start/stop/resume support at some point ...

Starting CK web service on 172.17.0.2:3366 ...

I have to explicitly type in the values of ${WFE_HOST} and ${WFE_PORT} into http://<WFE_HOST>:<WFE_PORT>/web?, which is cumbersome, error-prone and not easily automate-able.

I propose to enable launching the CK web service as follows:

$  ck start web \
    --host=`hostname -i` --port=${CK_PORT} \
    --wfe_host=${WFE_HOST} --wfe_port=${WFE_PORT}

Then, the Dockerfile file would look something like:

FROM ubuntu:16.04
MAINTAINER Anton Lokhmotov <anton@dividiti.com>

# Install standard packages.
RUN apt-get update && apt-get install -y \
    python-all \
    git

# Install the core Collective Knowledge (CK) module.
ENV CK_HOME=/root/CK \
    CK_TOOLS=/root/CK_TOOLS \
    CK_ROOT=${CK_HOME}/ck-core \
    PATH=${CK_ROOT}/bin:${PATH}

RUN mkdir -p ${CK_HOME} && git clone https://github.com/ctuning/ck.git ${CK_ROOT}
RUN mkdir -p ${CK_TOOLS}

RUN cd ${CK_ROOT} && python setup.py install && python -c "import ck.kernel as ck"

# Install other CK modules.
RUN ck pull repo:ck-web

# Set the CK web service defaults.
ENV CK_PORT=3344 \
    WFE_PORT=3344 \
    WFE_HOST=localhost

# Listen on the CK port.
EXPOSE ${CK_PORT}

# Start the CK web service.
CMD ck start web \
    --host=`hostname -i` --port=${CK_PORT} \
    --wfe_host=${WFE_HOST} --wfe_port=${WFE_PORT}

[psyhtest]

With the capability to set up ${WFE_HOST} and ${WFE_PORT} explicitly, it may be worth also updating the ck setup kernel --wfe dialogue e.g.

=======================================================================
Loading current configuration ...
=======================================================================
*** Web front end control (through CK web server or third-party web server and CK php connector) ***

Current web front-end host: localhost
Current web front-end port: 3344
Current web front-end template: default

Enter new web front-end host (Enter to keep previous):
Enter new web front-end port (Enter to keep previous):
Enter new web front-end template (Enter to keep previous): 

[psyhtest]

With the latest CK changes (in particular, 8fcd77fc, a container can be started with e.g.:

$ docker run --rm -it -p ${WFE_PORT}:${CK_PORT} \
  --env CK_PORT=${CK_PORT} \
  --env WFE_PORT=${WFE_PORT} \
  --env WFE_HOST=${WFE_HOST} \
  ctuning/ck-ubuntu-16.04
Starting CK web service on 172.17.0.2:3355 (configured for access at 192.168.0.65:3344) ...

Once the CK changes are more thoroughly tested and stabilised, this issue can be closed.

[psyhtest]

An experimental CK Docker image is now available at a public repository:

$ docker pull ctuning/ck-ubuntu-16.04

The CK web service can be run locally and accessed at http://localhost:3344/ as follows:

$ docker run --rm -it ctuning/ck-ubuntu-16.04

The CK web service can be run on a remote server (at an address ${WFE_HOST} and with an opened port ${WFE_PORT}) and accessed at ${WFE_HOST}:${WFE_PORT} as follows:

$ export WFE_HOST=123.456.0.78 WFE_PORT=9999 CK_PORT=3344
$ docker run --rm -it -p ${WFE_PORT}:${CK_PORT} \
  --env WFE_HOST=${WFE_HOST} --env WFE_PORT=${WFE_PORT} --env CK_PORT=${CK_PORT} \
  ctuning/ck-ubuntu-16.04
Starting CK web service on 172.17.0.2:3344 (configured for access at 123.456.0.78:9999) ...

NB: The ${CK_PORT} variable must be defined but its value is inconsequential.