Arsse/README.md

# The Advanced RSS Environment

The Arsse is a news aggregator server, written in PHP, which implements multiple synchronization protocols. Unlike most other aggregator servers, The Arsse does not include a Web front-end (though one is planned as a separate project), and it relies on existing protocols to maximize compatibility with existing clients.

Information on how to install and use the software can be found in [the manual](https://thearsse.com/manual/), which is available online as well as with every copy of the software. This readme file instead focuses on how to set up a programming environment to modify the source code.

# Installing from source

The main repository for The Arsse can be found at [code.mensbeam.com](https://code.mensbeam.com/MensBeam/arsse/), with a mirror also available [at GitHub](https://github.com/mensbeam/arsse/). The GitHub mirror does not accept bug reports, but the two should otherwise be equivalent.

[Composer](https://getcomposer.org/) is required to manage PHP dependencies. After cloning the repository or downloading a source code tarball, running `composer install` will download all the required dependencies, and will advise if any PHP extensions need to be installed. If not installing as a programming environment, running `composer install -o --no-dev --no-scripts` is recommended.

# Repository structure

## Library code

The code which runs The Arsse, contained in `/arsse.php`, is only a short stub: the application itself is composed of the classes found under `/lib/`, with the main ones being:

| Path           | Description                                             |
|----------------|---------------------------------------------------------|
| `CLI.php`      | The command-line interface, including its documentation |
| `Conf.php`     | Configuration handling                                  |
| `Database.php` | High-level database interface                           |
| `Db/`          | Low-level database abstraction layer                    |
| `REST/`        | Protocol implementations                                |
| `REST.php`     | General protocol handler for CORS, HTTP auth, etc.      |
| `Arsse.php`    | Singleton glueing the parts together                    |

The `/lib/Database.php` file is the heart of the application, performing queries on behalf of protocol implementations or the command-line interface.

Also necessary to the functioning of the application is the `/vendor/` directory, which contains PHP libraries which The Arsse depends upon. These are managed by Composer.

## Supporting data files

The `/locale/` and `/sql/` directories contain human-language files and database schemata, both of which are occasionally used by the application in the course of execution. The `/www/` directory serves as a document root for a few static files to be made available to users by a Web server.

The `/dist/` directory, on the other hand, contains general and system-specific build files, and samples of configuration for Web servers and other system integration. These are not used by The Arsse itself, but are used during the process of preparing new releases for supported operating systems.

## Documentation

The source text for The Arsse's manual can be found in `/docs/`, with pages written in [Markdown](https://spec.commonmark.org/current/) and converted to HTML [with Daux](#building-the-manual). If a static manual is generated its files will appear under `/manual/`.

The Arsse also has a UNIX manual page, also written in Markdown, which can be found under `/manpages/`. [Pandoc](https://pandoc.org/) is needed to convert it to the appropriate format, with the results stored under `/dist/man/`.

In addition to the manuals the files `/README.md` (this file), `/CHANGELOG`, `/UPGRADING`, `/LICENSE`, and `/AUTHORS` also document various things about the software, rather than the software itself.

## Tests

The `/tests/` directory contains everything related to automated testing. It is itself organized as follows:

| Path               | Description                                                                        |
|--------------------|------------------------------------------------------------------------------------|
| `cases/`           | The test cases themselves, organized in roughly the same structure as the code     |
| `coverage/`        | (optional) Generated code coverage reports                                         |
| `docroot/`         | Sample documents used in some tests, to be returned by PHP's basic HTTP server |
| `lib/`             | Supporting classes which do not contain test cases                                 |
| `bootstrap.php`    | Bootstrap script, equivalent to `/arsse.php`, but for tests                        |
| `phpunit.dist.xml` | PHPUnit configuration file                                                         |
| `server.php`       | Simple driver for the PHP HTTP server used during testing                          |

PHPUnit's configuration can be customized by copying its configuration file to `/tests/phpunit.xml` and modifying the copy accordingly.

## Tooling

The `/vendor-bin/` directory houses the files needed for the tools used in The Arsse's programming environment. These are managed by the Composer ["bin" plugin](https://github.com/bamarni/composer-bin-plugin) and are not used by The Arsse itself. The following files are also related to various programming tools:

| Path              | Description                                              |
|-------------------|----------------------------------------------------------|
| `/.gitattributes` | Git settings for handling files                          |
| `/.gitignore`     | Git file exclusion patterns                              |
| `/.php_cs.dist`   | Configuration for [php-cs-fixer](https://cs.symfony.com) |
| `/.php_cs.cache`  | Cache for php-cs-fixer                                   |
| `/composer.json`  | Configuration for Composer                               |
| `/composer.lock`  | Version synchronization data for Composer                |
| `/RoboFile.php`   | Task definitions for [Robo](https://robo.li/)            |
| `/robo`           | Simple wrapper for executing Robo on POSIX systems       |
| `/robo.bat`       | Simple wrapper for executing Robo on Windows             |

In addition the files `/package.json` and `/postcss.config.js` as well as the `/node_modules/` directory are used by [Yarn](https://yarnpkg.com/) and [PostCSS](https://postcss.org/) when modifying the stylesheet for The Arsse's manual.

# Common tasks

We use a tool called [Robo](https://robo.li/) to simplify the execution of common tasks. It is installed with The Arsse's other dependencies, and its configured tasks can be listed by executing `./robo` without arguments.

## Running tests

The Arsse has an extensive [PHPUnit](https://phpunit.de/) test suite; tests can be run by executing `./robo test`, which can be supplemented with any arguments understoof by PHPUnit. For example, to test only the Tiny Tiny RSS protocol, one could run `./robo test --testsuite TTRSS`.

There is also a `test:quick` Robo task which excludes slower tests, and a `test:full` task which includes redundant tests in addition to the standard test suite

### Test coverage

Computing the coverage of tests can be done by running `./robo coverage`, after which an HTML-format coverage report will be written to `/tests/coverage/`. Either [PCOV](https://github.com/krakjoe/pcov), [Xdebug](https://xdebug.org), or [phpdbg](https://php.net/manual/en/book.phpdbg.php) is required for this. PCOV is generally recommended as it is faster than Xdebug; phpdbg is faster still, but less accurate. If using either PCOV or Xdebug, the extension need not be enabled globally; PHPUnit will enable it when needed.

## Enforcing coding style

The [php-cs-fixer](https://cs.symfony.com) tool, executed via `./robo clean`, can be used to rewrite code to adhere to The Arsse's coding style. The style largely follows [PSR-2](https://www.php-fig.org/psr/psr-2/) with some exceptions:

- Classes, methods, and functions should have their opening brace on the same line as the signature
- Anonymous functions should have no space before the parameter list

## Building the manual

The Arsse's user manual, made using [Daux](https://daux.io/), can be compiled by running `./robo manual`, which will output files to `/manual/`. It is also possible to serve the manual from a test HTTP server on port 8085 by running `./robo manual:live`.

### Rebuilding the manual theme

The manual employs a custom theme derived from the standard Daux theme. If the standard Daux theme receives improvements, the custom theme can be rebuilt by running `./robo manual:theme`. This requires that [NodeJS](https://nodejs.org) and [Yarn](https://yarnpkg.com/) be installed, but JavaScript tools are not required to modify The Arsse itself, nor the content of the manual.

## Building the man page

The Arsse's UNIX manual page is authored in Markdown, and must be converted to the native roff format using [Pandoc](https://pandoc.org/). This can be done by running `./robo manpage`, which will output appropriate files to `/dist/man/`. The conversion should not be done manually as there is post-processing required for optimal output.

## Packaging a release

Producing release packages is done by running `./robo package`. This performs the following operations:

- Duplicates a [Git](https://git-scm.com/) working tree with the commit (usually a release tag) to package
- Generates UNIX manual pages with [Pandoc](https://pandoc.org/)
- Generates the HTML manual
- Installs runtime Composer dependencies with an optimized autoloader
- Deletes numerous unneeded files
- Exports the default configuration of The Arsse to a file
- Compresses the remaining files into a tarball