Gearwheel is a tool set used mostly for building docker images. But it is more, than just a builder.

• It makes use of 'dockerised' tool's (which runs inside docker) as simple as using local installed tools.
• And it makes run docker containers inside dind (docker in docker) as simple as running them just in host's docker.

Yes it is simple, look inside the example file ./build-example-project.sh You can write your OPS script like there is no docker around, but it is.

Gearwheel is currently a wrapper written in shell (sh).

• Transparent substitution of commands like docker docker-compose mvn and such (potentially any program) with their dockerised versions;
  • Useful if the tool is ugly and dirty and you just don't want to install it on the host;
  • Useful when incompatible tools rejects to run on the same host;
  • Useful to get new and even edge versions of tools on industrial distributives.
• Run tools using 'services' like dind and use them seamless with dockerised tools;
  • Same as above including build in modern dind while host's dockerd is 1.12+;
  • Per build service isolation.
• Export docker images and docker volumes standard way.
  • After build finishes, the service will automatic export its artifacts.

You can use CI/CD machine with only:

• Coreutils;
• Docker v1.12+;
• Gearwheel.

No other tools needed, you can even use coreutils from busybox:latest inside your build script.

You can check it works by just run example build. E.g.: Just run ./Jenkins_example-project

No, you don't need Jenkins, that's just the name of start script. ./Jenkins_example-project 'emulates' build server's work:

• sets some environment;
• changes working directory;
• starts the build: ./build-example-project.sh.

Build script ./build-example-project.sh is written using shell (sh) and contains several example build tasks. After test build finishes, you will get example docker artifacts in ./workdir/docker-target/.

• EXAMPLE #1 build docker image from Dockerfile. Replace content between two horizontal lines in ./build-example-project.sh:

# -----------------------------------------------------------------------------

pushd /directory/with/Dockerfile
docker build -t targettag:latest .
popd

# -----------------------------------------------------------------------------

• EXAMPLE #2 build docker project with docker-compose.yaml. Replace content between two horizontal lines in ./build-example-project.sh:

# -----------------------------------------------------------------------------

pushd /directory/with/docker-compose.yaml
docker-compose build
docker-compose up -d
docker-compose down
popd

# -----------------------------------------------------------------------------

• First you need a project with complete build script like: unzip -> change directory -> perform build steps;

• Create or select 'wheels' (profiles) useful for your build job and set it in GEARWHEEL_WHEELS variable;

  • GEARWHEEL_WHEELS variable may contain one or more space separated profile names from local/etc/gearwheel.d/*. If there are duplicated tools inside them, first wheel (profile) will be used first;

  • If you want to create new wheel (profile), use ./local/etc/gearwheel.d/multigear.sh. It will create new wheel from the DEFAULT one.

• Name your build job and set the name in GEARWHEEL_TASKID variable;

  • You don't have to do it, GEARWHEEL_TASKID will be auto set to some ugly string if not set.

• Using ./build-example-project.sh add your build script in build-*.sh. Your build jobs should be between two horizontal lines;

  • Actually, you can run build anywhere, but for first time better place your tasks between the lines.

• Make sure the services set in build-*.sh script are okay.

  • Currently you are to use Ugly-style service start technique, but all examples will be always accessible in ./build-example-project.sh;

  • The service is controlled with wheelctl function: wheelctl [ start | stop | restart | status ] serviceName;

  • If you stop the service manually, then all its state will be lost. Be sure you extract all the data before stop service;

  • All services stops automatically on script's exit. In such case the data will be extracted to certain directories (watch info messages).

• Run build-*.sh with GEARWHEEL_WHEELS and GEARWHEEL_TASKID variables set;

  • If GEARWHEEL_WHEELS is not set, then DEFAULT wheel is used;

  • If GEARWHEEL_TASKID is not set, them GEARWHEEL_TASKID is generated;

  • You can use ./Jenkins_example-project to prepare a starter script for your project. It sets variables and runs build-*.sh;

  • If you running script as part of CI/CD pipeline, make sure env variables are set right.

• You can use Gearwheel on desktop:
  • use something like ./Jenkins_example-project script as starter script;
• You can use it on a build server:
  • use ./Jenkins_example-project to find out what variables to set for executing build-*.sh from build server's pipeline;
• You can use it other way.

• Add and test more tools;
• Optimize code to run in Apline linux and jenkins:alpine;
• Code clean:
  • VERBOSE_LEVELs;
  • More useful diagnostic messages;
  • Maybe slow parts rewrite;
• Test in various sutuations;
• Add service busybox;
• Readme add FAQ;
• Fix using without dind.