Source-to-Image builder for Common Lisp applications on OpenShift
Clone or download

README.md

Build Status

Common Lisp + Quicklisp OpenShift Build Image

This repository contains the source for building a Quicklisp based Common Lisp application as a reproducible docker image using source-to-image. This docker image is CentOS based, but the project includes Dockerfile.rhel7 for creating a RHEL based image as well. The resulting images can be run using docker.

Usage

To build a simple sample-lisp-app application using standalone S2I and then run the resulting image with docker execute:

$ s2i build https://github.com/container-lisp/sample-lisp-app containerlisp/lisp-10-centos7 sample-lisp-app
$ docker run -p 8080:8080 sample-lisp-app

Accessing the application:

Run interactively as above, you can access the sample-lisp-app like so:

$ curl 127.0.0.1:8080

You will likely, however, prefer OpenShift, where applications are created like so:

$ oc new-app containerlisp/lisp-10-centos7~git://github.com/container-lisp/sample-lisp-app

A slynk server will be started on port 4005 for every application. With OpenShift, you can forward port 4005 to your local host and connect to it with SLY for interactive Emacs based development. Just identify the pod running your container with oc get pods, and then....

oc port-forward sample-lisp-app-1-h5o5f 4005

Follow this up in Emacs with...

M-x sly-connect RET RET

To teach Emacs how to translate filenames between the remote and local machines, you'll need to define sly-filename-translations.

There are a number of excellent screencasts and tutorials on using SLY on the project web site at https://github.com/joaotavora/sly.

Note that slynk, by default, is configured to only listen on the localhost loopback device. This works well with OpenShift port forwarding, as above, but if you run this container by hand you will want to use the docker --net host option to allow for connections to swank.

Also note that instead of using sly, you can also decide to use slime, the traditional emacs common lisp development environment. See below the section about environment variable DEV_BACKEND on how to do this.

To install this image along with sample application template into OpenShift, run the following as the cluster manager:

$ oc create -f lisp-image-streams.json -n openshift
$ oc create -f lisp-web-basic-s2i.json -n openshift

Environment variables

To set these environment variables, you can place them as a key value pair into a .s2i/environment file inside your source code repository.

  • APP_SYSTEM_NAME

    The name that quicklisp will know this application by and which will become the name of the directory in the quicklisp local-project subdirectory, where the application source code will be copied into and build and run from.

  • APP_EVAL

    SBCL evaluates this lisp form after ql:quickload'ing :$APP_SYSTEM_NAME, e.g. "(webapp:start-webapp)". This only happens when :$APP_SCRIPT is not used.

  • APP_SCRIPT

    SBCL loads this script and executes it instead of evaluating :$APP_EVAL. This script needs to take care of setting up and quickloading the application but thus gives full control over the startup process. Note that this variable should point to a relative path, which will be within the quicklisp project defined by APP_SYSTEM_NAME, e.g. ".s2i/run.lisp".

  • APP_BUILD_SCRIPT

    SBCL loads this script and executes it during the build process. If this is used, :$APP_EVAL and $APP_SYSTEM_NAME will not be used for quickloading and building the app. Instead, the script specified needs to take care of setting up and quickloading the application but thus gives more control over the build process. Note that this variable should point to a relative path, which will be within the quicklisp project defined by APP_SYSTEM_NAME, e.g. ".s2i/build.lisp".

  • APP_MEM

    This value will be passed to sbcl via --dynamic-space-size and should be set to the amount of memory the application needs. It will be used for both building the image as well as running it. Its default value is 90% of available memory as reported by cgroups.

  • DEV_BACKEND

    Set this variable to slynk or swank to choose the development backend to start, or leave it unset to start no backend at all.

  • DEV_BACKEND_PORT

    The default slynk/swank port is 4005. Set this value to something else for your application to use a different port (e.g. if your application needs to use this port). This setting will only come into effect when a development backend has been selected via DEV_BACKEND.

Public Container Images

The centos7-based S2I images are published on dockerhub, as containerlinux/lisp-10-centos7. Image tags are as follows:

  • latest: the most recent build of the very latest quicklisp, SBCL and OS bits.

  • Quicklisp dist version date (eg. 20181210): The latest build based on this quicklisp distribution version. If you use this tag, the quicklisp bits will never change, but the underlying OS and SBCL bits may.

  • Git commit hash (eg. b6ef12a): The semantics of this tag are the same as above. It is provided as a convenience in order to map back to the original source version.

  • Quicklisp dist version date + travis-ci build number (eg. 20181210.26): This identifies a specific build for a specific quicklisp distribution. This is a unique build, and will never change.