autodoc/README.md

# autodoc

[`autodoc`](https://github.com/ldericher/autodoc) is a simple [CI](https://en.wikipedia.org/wiki/Continuous_integration) system optimized for document creation.

## Quick Start Guide

1. Install [Docker CE](https://docs.docker.com/install/)

1. Clone or download the `autodoc` repository, open a terminal inside the [example_docs](https://github.com/ldericher/autodoc/tree/master/example_docs) directory

1. Deploy an `autodoc` container:
   ```bash
   docker run --rm -it \
     --name autodoc \
     --volume "${PWD}":/docs \
     --user "$(id -u):$(id -g)" \
     ldericher/autodoc
   ```

   The contents of the directory are now being watched by `autodoc`!

   When deploying an `autodoc` container, mount your document root to `/docs`. You *should* also set the container's UID and GID.

1. Edit some stuff, save, then watch the magic (and the terminal output)

## Where not to use `autodoc`

`autodoc` is **not** a solution for Continuous Integration of large scale systems software! `autodoc` excels at building a large number of independent, small files.

## Prime use case: Nextcloud

Nextcloud is a "safe home for all your data" that can [easily be deployed using docker-compose](https://hub.docker.com/_/nextcloud).  
Add an `autodoc` container to create directories where PDFs are automatically held up to date for all your documents. This extends upon the "[Base version - apache](https://hub.docker.com/_/nextcloud#base-version---apache)" of the Nextcloud compose deployment.

```yaml
version: '2'

volumes:
  documents:

services:
  app:
    volumes:
      - documents:/opt/autodoc

  autodoc:
    restart: always
    image: ldericher/autodoc
    user: "UID:GID"
    volumes:
      - documents:/docs
```

The "user" key should be set to the same numeric IDs used for the nextcloud worker processes! To find the right IDs, issue `docker-compose exec app sh -c 'id -u www-data; id -g www-data'`.  
For the apache containers, this should evaluate to "33:33".

To begin, add the mounted `/opt/autodoc` as a local external storage to your Nextcloud instance.  
You might need to setup the permissions on your new volume using `docker-compose exec app chown -R www-data:www-data /opt/autodoc`.

## Basic functionality

`autodoc` uses `inotifywait` from [inotify-tools](https://github.com/rvoicilas/inotify-tools) to recursively watch a Linux file system directory.

For each file change, `autodoc` searches relevant build instruction files (Makefiles etc.) and kicks off build processes accordingly.

## Concept: Source patterns

To avoid unnecessary rebuilds and self-triggering, `autodoc` uses "source patterns" to filter for the relevant build instructions.  
A source pattern is a `bash` regular expression matching any filename that should be regarded as a "source file" to the build instruction file.

For instance, if a Makefile instructs how to build from Markdown source files, that Makefile's source pattern should likely be `\.md$`.

## Creating an automated build

In general, just put your source files into any (sub-)directory watched by `autodoc`. Add a build instruction file.

On each file change, its containing directory is searched for a build instruction file. Watched parent directories are also probed for further build instructions.  
Every relevant instruction file will be executed as found.

You may combine build instruction systems to your liking.

## Build instruction systems

### GNU Make (Makefiles)

`autodoc` supports standard Makefiles.  
`Makefile`s must contain a SRCPAT annotation comment as follows, where `<regex>` is the source pattern as above.

```Makefile
#@SRCPAT <regex>
```

If there are multiple SRCPAT annotations, the lowermost one will be used.

##### Advanced Make options

You may add a PHONY target "autodoc" which will be built *instead* of the default target.

```Makefile
.PHONY: autodoc
autodoc:
  @echo "Hello World!"
```