The mlan/gitweb repository

Provides a Gitweb — a Git web interface (web frontend to Git repositories) — docker image (non official).

Features

• Gitweb, read access only
• Small image size based on Alpine Linux
• Health check
• Demo based on docker-compose.yml and Makefile files

Tags

The MAJOR.MINOR.PATCH SemVer is used. In addition to the three number version number you can use two or one number versions numbers, which refers to the latest version of the sub series. The tag latest references the build based on the latest commit to the repository.

The mlan/gitweb repository contains a multi staged built. You select which build using the appropriate tag from base and full . The image with the tag base contains Gitweb. The full tag also include support for highlighting.

To exemplify the usage of the tags, lets assume that the latest version is 1.0.0. In this case latest, 1.0.0, 1.0, 1, all identify the same image.

Usage

You can start a mlan/gitweb container from the command line. The example below assumes that you are in a git directory and will start a web server that can be accessed on http://localhost:8080.

docker run -d --name repoweb -e PROJECTS_LIST= -v $(pwd)/.git:/var/lib/git:ro -p 127.0.0.1:8080:80 mlan/gitweb

You can also try out the demo that comes with the github repository.

Docker compose example

Using docker compose, the following docker-compose.yml file will start a Gitolite server and Gitweb server.

name: demo

services:
   repo:
    image: jgiannuzzi/gitolite
    ports:
      - "22:22"
    volumes:
      - repo-data:/var/lib/git

  repo-gui:
    image: mlan/gitweb
    ports:
      - "8080:80"
    depends_on:
      - repo
    volumes:
      - repo-data:/var/lib/git:ro

volumes:
  repo-data:

For the above example to produce anything interesting the volume repo-data must include at least one git repository.

Demo

This repository contains a demo directory which hold the docker-compose.yml file as well as a Makefile which might come handy. To run the demo first clone the github repository.

git clone https://github.com/mlan/docker-github.git

From within the demo directory you can start the container simply by typing:

make up

The you can connect to the Gitweb server by typing

make web

When you are done testing you can destroy the test container by typing

make destroy

Environment variables

When you start the mlan/gitweb container, you can configure Gitweb by passing one or more environment variables or arguments on the docker run command line.

PROJECTROOT

The directories where your projects are. Must not end with a slash. Default: PROJECTROOT=/var/lib/git/repositories

PROJECTS_LIST

Define which file Gitweb reads to learn the git projects. If set to empty string; Gitweb simply scan the PROJECTROOT directory. Default: PROJECTS_LIST=/var/lib/git/projects.list

SERVER_NAME

The nginx server_name directive and determine which server block is used for a given request. Since there only one block in this application the server_name is not important and can be anyting but empty.

With gitweb the Nginx server_name is displayed in the browser tab. And since it can be chosen freely, it can be seen to have a decorative function.

Gitolite

If you have Gitolie and Gitweb running on the same machine, you will be able to browse the Gitolite repositories simply by having the services sharing file systems. The docker compose example above is doing exactly that.

The volume repo-data allow the containers share files. The volume has similar mount point in both containers, repo-data:/var/lib/git. The only difference is that it is sufficient to mount it read-only on the Gitweb container. The default values of both environment variables; PROJECTROOT and PROJECTS_LIST are adequate.

It is of cause also possible to start the Gitweb container using the docker command:

docker run -d --name repo-gui -v repo-data:/var/lib/git:ro -p 127.0.0.1:8080:80 mlan/gitweb

Implementation

Here some implementation details are presented.

Container init scheme

When the container is started, execution is handed over to the script docker-entrypoint.sh. It has 2 stages; 1) run all entry scripts in /etc/docker/entry.d/, 2) execute command in CMD ["nginx", "-g", "daemon off;"].

The entry scripts are responsible for tasks like, generate configurations, and spawning processes.

Build assembly

The entry scripts, discussed above, as well as other utility scrips are copied to the image during the build phase. The source file tree was designed to facilitate simple scanning, using wild-card matching, of source-module directories for files that should be copied to image. Directory names indicate its file types so they can be copied to the correct locations. The code snippet in the Dockerfile which achieves this is show below.

COPY	src/*/bin $DOCKER_BIN_DIR/
COPY	src/*/entry.d $DOCKER_ENTRY_DIR/
COPY	src/*/envsubst $DOCKER_ENVSUBST_DIR/