Themeing support

docs/content/configuration.md

@@ -16,6 +16,7 @@ title = "Bartholomew"
 # logo = "URL to logo"
 base_url = "http://localhost:3000"
 about = "This site is generated with Bartholomew, the Spin micro-CMS. And this message is in site.toml."
+theme = "fermyon"
 
 [extra]
 copyright = "The Site Authors"
@@ -31,6 +32,7 @@ It has a few pre-defined fields:
 - logo: a URL or static path to your logo
 - base_url: a base URL that templates can use to construct full URLs to content. This can be overridden by setting the `-e BASE_URL="https://example.com"` environment variable for Spin.
 - about: a brief description of the site
+- theme: the name of the theme for the website from the `/themes/` folder
 
 You can define your own fields in the `[extra]` section. Anything in `[extra]` is not
 used by the system itself. But it's a useful way to pass information from one central

docs/content/themes.md

@@ -0,0 +1,84 @@
+title = "Bartholomew themes"
+date = "2022-07-20T22:44:01.300319091Z"
+
+[extra]
+
+---
+
+Bartholomew supports theming which allows for easy customization of the site along with the user defined tempaltes.
+
+## Adding a theme
+
+Once the initial site has been setup using the [quickstart section](/quickstart). Create a themes folder where you will be able to download different themes.
+```bash
+mkdir themes
+```
+
+Once the folder is created, different themes can be added as submodules to the folder which can then in turn be used to theme the site.
+
+```bash
+cd themes
+git submodule add <Source_to_the_theme>
+```
+
+Multiple themes can be added to the themes directory but only one of them will be active at a given time as described in the next section.
+
+## Configuring the site to use the theme
+
+To choose a theme for the website, the `theme` attribute in `config/site.toml` must be configured, where the value is the name of the theme as found in the `themes/` folder.
+
+```toml
+title = "Bartholomew Documentation"
+base_url = "http://localhost:3000"
+about = "The Micro-CMS for WebAssembly and Spin"
+theme = "<theme-directory>"
+
+[extra]
+copyright = "Fermyon"
+github = "https://github.com/fermyon/bartholomew"
+twitter = "https://twitter.com/fermyontech"
+ga_measurement_id = ""
+
+date_style = "%B %e, %Y"
+```
+One more step that needs to be done before themes are fully available to the site is to the change the static file server component in `spin.toml` configuration so that it provides the static assets of the selected theme. The convention of mounting the static assets of the themes before the user defined static assets is recommened.  
+
+```
+.
+.
+.
+
+[[component]]
+source = "modules/spin_static_fs.wasm"
+id = "fileserver"
+files = [ {source = "themes/<name of theme>/static", destination ="/"}, { source = "static/", destination = "/" }, ]
+[component.trigger]
+route = "/static/..."
+
+```
+
+
+## Template precedence
+
+When a theme is enabled for a site, both the user defined and theme-provided assets like the templates, scripts and static assets will be available. In case that a theme provided asset and user provided asset have the same name, the user-defined asset takes precedence. This allows for the user to override the theme to allow for customization. 
+
+As an example, if both `templates/main.hbs` and `themes/<name of thene>/templates/main.hbs` exist, the user defined `templates/main.hbs` takes precedence leading to the rendering engine using the user defined template overriding the theme.
+
+## Creating a Theme
+
+Creating  a theme for Bartholomew is easy. Create a new folder and initialize it.
+
+```
+mkdir custom_theme
+cd custom_theme
+git init
+```
+
+Once the git repository is initialized, create the three required directories.
+```
+mkdir templates scripts static
+```
+
+Create the custom theme by placing the handlebar templates in the `template/` folder while the Rhai scripts are places in the `scripts/` folder. All the static assets like the images, JS and CSS are placed in the static folder. For reference on creating templates, refer to the [templates section](/templates).
+
+Once the required changes are done, commit and push the changes to a remote repository, so as to allow for the theme to cloned as a submodule that can be used for themeing a site. 

docs/package.json

@@ -31,7 +31,7 @@
     "sass": "^1.49.9"
   },
   "scripts": {
-    "spin": "nodemon --watch content --watch static --watch templates --ext md,rhai,hbs,css,js --verbose --legacy-watch --signal SIGINT --exec 'spin up --file spin.toml'",
+    "spin": "nodemon --watch content --watch static --watch templates --watch themes --ext md,rhai,hbs,css,js --verbose --legacy-watch --signal SIGINT --exec 'spin up --file spin.toml'",
     "styles": "npx parcel build static/sass/styles.scss --dist-dir static/css --no-optimize"
   }
 }

docs/spin.toml

@@ -8,13 +8,13 @@ trigger = { type = "http", base = "/" }
 [[component]]
 source = "modules/bartholomew.wasm"
 id = "bartholomew"
-files = [ "content/**/*" , "templates/*", "scripts/*", "config/*"]
+files = [ "content/**/*" , "templates/*", "themes/**/*", "scripts/*", "config/*"]
 [component.trigger]
 route = "/..."
 
 [[component]]
 source = "modules/spin_static_fs.wasm"
 id = "fileserver"
-files = [ { source = "static/", destination = "/" } ]
+files = [{ source = "static/", destination = "/" }, ]
 [component.trigger]
 route = "/static/..."

docs/templates/content_sidebar.hbs

@@ -8,6 +8,7 @@
             <li><a href="{{site.info.base_url}}/quickstart">Quickstart</a></li>
             <li><a href="{{site.info.base_url}}/templates">Templates</a></li>
             <li><a href="{{site.info.base_url}}/configuration">Configuration</a></li>
+            <li><a href="{{site.info.base_url}}/themes">Themes</a></li>
             <li><a href="{{site.info.base_url}}/scripting">Scripting</a></li>
             <li><a href="{{site.info.base_url}}/markdown">Markdown guide</a></li>
         </ul>

src/bartholomew.rs

@@ -43,8 +43,18 @@ pub fn render(req: Request) -> Result<Response> {
     }
     eprintln!("Base URL: {:?}", &config.base_url);
 
+    // If a theme is specifed, create theme path
+    let theme_dir = if config.theme.is_some() {
+        let mut path: PathBuf = PathBuf::from(THEME_PATH);
+        path.push(config.theme.as_ref().unwrap());
+        Some(path)
+    } else {
+        None
+    };
+
     let mut engine = template::Renderer::new(
         PathBuf::from(TEMPLATE_PATH),
+        theme_dir,
         PathBuf::from(SCRIPT_PATH),
         PathBuf::from(CONTENT_PATH),
     );

src/response.rs

@@ -9,6 +9,7 @@ use std::io::Write;
 
 pub const CONTENT_PATH: &str = "/content/";
 pub const TEMPLATE_PATH: &str = "/templates/";
+pub const THEME_PATH: &str = "/themes/";
 pub const SCRIPT_PATH: &str = "/scripts/";
 pub const CONFIG_FILE: &str = "/config/site.toml";
 

src/template.rs

@@ -18,6 +18,7 @@ pub struct SiteInfo {
     pub logo: Option<String>,
     pub base_url: Option<String>,
     pub about: Option<String>,
+    pub theme: Option<String>,
     pub extra: BTreeMap<String, String>,
 }
 
@@ -71,6 +72,7 @@ impl From<Content> for PageValues {
 /// Renderer can execute a handlebars template and render the results into HTML.
 pub struct Renderer<'a> {
     pub template_dir: PathBuf,
+    pub theme_dir: Option<PathBuf>,
     pub script_dir: PathBuf,
     pub content_dir: PathBuf,
     pub show_unpublished: bool,
@@ -79,9 +81,15 @@ pub struct Renderer<'a> {
 
 impl<'a> Renderer<'a> {
     /// Create a new renderer with the necessary directories attached.
-    pub fn new(template_dir: PathBuf, script_dir: PathBuf, content_dir: PathBuf) -> Self {
+    pub fn new(
+        template_dir: PathBuf,
+        theme_dir: Option<PathBuf>,
+        script_dir: PathBuf,
+        content_dir: PathBuf,
+    ) -> Self {
         Renderer {
             template_dir,
+            theme_dir,
             script_dir,
             content_dir,
             show_unpublished: false,
@@ -97,15 +105,34 @@ impl<'a> Renderer<'a> {
     /// Load the template directory.
     pub fn load_template_dir(&mut self) -> Result<(), anyhow::Error> {
         self.register_helpers();
+
+        // If there is a theme, load the templates provided by it first
+        // Allows for user defined tempaltes to take precedence
+        if self.theme_dir.is_some() {
+            let mut templates = self.theme_dir.as_ref().unwrap().to_owned();
+            templates.push("templates");
+            self.handlebars
+                .register_templates_directory(".hbs", templates)?;
+        }
         self.handlebars
             .register_templates_directory(".hbs", &self.template_dir)?;
         Ok(())
     }
 
     /// Load the scripts directory
     pub fn load_script_dir(&mut self) -> anyhow::Result<()> {
+        let mut theme_scripts: Vec<PathBuf> = Vec::new();
+
+        // If theme has scripts,load it first to follow proper precedence
+        if self.theme_dir.is_some() {
+            let mut theme_scripts_path = self.theme_dir.as_ref().unwrap().to_owned();
+            theme_scripts_path.push("scripts");
+            theme_scripts = crate::content::all_files(theme_scripts_path)?;
+        }
+        let user_scripts = crate::content::all_files(self.script_dir.clone())?;
         // TODO: rewrite all_files so we don't need to clone here.
-        let scripts = crate::content::all_files(self.script_dir.clone())?;
+        let scripts = [theme_scripts, user_scripts].concat();
+
         for script in scripts {
             // Relative file name without extension. Note that we skip any file
             // that doesn't have this.