Add container image and document usage

.goreleaser.yml

@@ -20,6 +20,19 @@ builds:
       - goos: linux
         goarch: arm
         goarm: '7'
+
+dockers:
+  - id: goveal
+    goos: linux
+    goarch: amd64
+    goarm: ''
+    ids:
+      - goveal
+    image_templates:
+      - ghcr.io/baez90/goveal:{{ .Tag }}
+      - ghcr.io/baez90/goveal:{{ .Major }}
+    dockerfile: ./build/docker/goveal.dockerfile
+
 archives:
   - replacements:
       darwin: Darwin

README.md

@@ -2,14 +2,23 @@
 
 [![Actions Status](https://github.com/baez90/goveal/workflows/Go/badge.svg)](https://github.com/baez90/goveal/actions)
 
-Goveal is very small and very simple tool that reads Markdown from a given file, renders it into a HTML template and
-serves it as local HTTP server. Right now Goveal uses Reveal.js 4.1.2 to create presentations and therefore also
-includes all features of Reveal.js 4.1.2.
+Goveal is very small and very simple tool that reads Markdown from a given file, renders it into an HTML template and serves it as local HTTP server.
+Right now Goveal uses Reveal.js 4.2.1 to create presentations and therefore also includes all features of Reveal.js 4.2.1.
+
+In contrary to Reveal.js `goveal` ships with its own Markdown parser and renderer which is why some features are working slightly different from Reveal.js.
+See [Markdown](#markdown) for further details.
+
+Besides all features from Reveal.js `goveal` comes with first class support for [mermaid-js](https://mermaid-js.github.io/).
+Just inline your diagrams as code and enjoy!
 
 ## Install
 
 The easiest and fastest way to install Goveal is to use a pre-built binary from the [releases](https://github.com/baez90/goveal/releases/latest).
 
+There's also a pre-built container image available you can use if you don't want to download the binary.
+
+### Build from source
+
 If you have Go in the latest version installed you can also build your own version of Goveal:
 
 ```shell
@@ -21,46 +30,88 @@ Requirements:
 - [task](https://taskfile.dev/)
 - _Optional:_ [goreleaser](https://goreleaser.com/) (for `task snapshot-release` to build all binaries)
 
-_Note: All script tasks in the [Taskfile.yml](Taskfile.yml) are meant to be executed with Linux/MacOS. Binaries for Windows are provided but not tested!_ 
+_Note: All script tasks in the [Taskfile.yml](Taskfile.yml) are meant to be executed with Linux/MacOS. Binaries for
+Windows are provided but not tested!_
 
 ## Usage
 
+### Local installation
+
 ```bash
 goveal serve ./slides.md
 ```
 
 | Param            | Description                                   | Default value           |
-| ------------------------ | ---------------------------------------------------------------------------- | ----------------------- |
-| `--host`                 | Hostname the binary is listening on                                          | `localhost`             |
+| ---------------- | --------------------------------------------- | ----------------------- |
+| `--host`         | Hostname the binary is listening on           | `127.0.0.1`             |
 | `--port`         | Port the binary is listening on               | `2233`                  |
-| `--code-theme`           | highlight.js theme to use                                                    | `monokai`               |
-| `--transition`           | Transition effect to show between slides                                     | `none`                  |
-| `--navigationMode`       | Navigation mode to use when using the cursor keys to navigate through slides | `default`               |
 | `--config`       | Path to the config file see [config](#config) | `$HOME/goveal:./goveal` |
-| `--horizontal-separator` | horizontal separator to split slides                                         | `===`                   |
-| `--vertical-separator`   | vertical separator to split slides                                           | `---`                   |
-| `--theme`                | reveal.js theme to use                                                       | `white`                 |
+| `--open-browser` | Open a browser after starting the web server  | `true`                  |
 | `-h` / `--help`  | shows help                                    |                         |
 
+### Container
+
+Assuming your slides are in a file called `slides.md` in the current directory, you can start the presentation like
+this:
+
+```shell
+podman/docker run --rm -ti -v `pwd`:/work -w /work -p 2233:2233 ghcr.io/baez90/goveal:0 serve --host 0.0.0.0 slides.md
+```
+
+By default `goveal` only listens on `127.0.0.1`. To allow traffic from outside of the container you've to change the
+binding to `0.0.0.0`.
+
 ## Config
 
 Goveal supports multiple configuration mechanisms. It tries to load a configuration file from `$HOME` or from `.`
 i.e. `$HOME/goveal.yaml` or `$HOME/goveal.yml` or `./goveal.yaml` and so on.
 
-Most options that can be set via commandline flags can also be set via configuration file (actually all but
-the `--config` switch does not make sense in the configuration file, does it? :wink:). It is more a convenience feature
-to be able to set a theme and so on and so forth for the presentation without having to pass it every time as parameter.
+The config allows setting a lot of options exposed by Reveal.js.
+There are still a few missing, and I won't guarantee to support all options in the future.
 
-Furthermore goveal supports configuration hot reloading i.e. you can play around with different themes and the rendered
+Furthermore, `goveal` supports configuration hot reloading i.e. you can play around with different themes and the rendered
 theme will be changed whenever you hit the save button!
 
 See also an example at [`./examples/goveal.yaml`](./examples/goveal.yaml).
+I try to keep the example up to date to cover **all** supported config options as kind of documentation.
 
-### Custom CSS
+## Markdown
+
+A good point to start is the [slides.md](examples/slides.md) in the `examples` directory.
+I try to showcase everyting possible with `goveal` in this presentation.
+
+The most remarkable difference between `goveal` and the `marked` driven Reveal.js markdown is how line numbers in listings are working:
+
+Reveal.js:
+
+<pre lang="no-highlight"><code>```cs [1-2|3|4]
+var i = 10;
+for (var j = 0; j < i; j++) {
+    Console.WriteLine($"{j}");
+}
+```</code></pre>
+
+`goveal`:
+
+<pre lang="no-highlight"><code>
+{line-numbers="1-2|3|4"}
+```cs
+var i = 10;
+for (var j = 0; j < i; j++) {
+    Console.WriteLine($"{j}");
+}
+```</code></pre>
+
+This is because the Markdown parser used in `goveal` currently does not support additional attributes for code blocks.
+
+## Custom CSS
 
 To add custom CSS as theme overrides use a config file and add the `stylesheets` property. It takes a list of relative (
 mandatory!) paths to CSS files that are included automatacally after the page was loaded so that they really overload
 everything added by Reveal and plugins.
 
-the sample configuration file [`./examples/goveal.yaml`](./examples/goveal.yaml) also contains a sample how to add
+Changes in the custom CSS files are monitored and propagated via SSE to the presentation immediately. 
+No page reload necessary!
+
+The sample configuration file [`./examples/goveal.yaml`](./examples/goveal.yaml) also contains a sample how to add
 custom CSS.

build/docker/goveal.dockerfile

@@ -0,0 +1,9 @@
+FROM gcr.io/distroless/static:nonroot
+
+USER nonroot:nonroot
+
+COPY --chown=nonroot:nonroot goveal /app/goveal
+
+EXPOSE 2233
+
+ENTRYPOINT ["/app/goveal"]

cmd/goveal/root.go

@@ -49,5 +49,4 @@ It is not required to restart the server when you edit the markdown - a simple r
 
 func init() {
 	rootCmd.PersistentFlags().StringVar(&cfgFile, "config", "", "config file (default is $HOME/.go-reveal-slides.yaml)")
-	rootCmd.PersistentFlags().StringVar(&workingDir, "working-dir", workingDir, "working directory to use")
 }

cmd/goveal/serve.go

@@ -24,7 +24,7 @@ import (
 )
 
 const (
-	defaultListeningPort uint16 = 3000
+	defaultListeningPort uint16 = 2233
 	defaultHost                 = "127.0.0.1"
 )