code: initial implementation

src/lib.rs

@@ -0,0 +1,128 @@
+use async_trait::async_trait;
+use axum::{response::Html, Extension, Router as AxumRouter};
+use loco_rs::{
+    app::{AppContext, Initializer},
+    controller::views::{ViewEngine, ViewRenderer},
+    errors::Error,
+    Result,
+};
+use minijinja::{filters::default, path_loader, Environment};
+#[cfg(feature = "autoreloader")]
+use minijinja_autoreload::AutoReloader;
+use serde::Serialize;
+use std::{marker::PhantomData, path::Path, sync::Arc};
+
+const TEMPLATES_DIR: &str = "assets/templates";
+
+#[derive(Clone)]
+pub struct MinijinjaView<'a> {
+    #[cfg(debug_assertions)]
+    pub template_dir: String,
+    #[cfg(not(feature = "autoreloader"))]
+    pub environment: Arc<std::sync::Mutex<Environment<'a>>>,
+    #[cfg(feature = "autoreloader")]
+    pub reloader: Arc<std::sync::Mutex<minijinja_autoreload::AutoReloader>>,
+
+    phantom: PhantomData<&'a ()>,
+}
+
+impl MinijinjaView<'_> {
+    pub fn build() -> Result<Self> {
+        Self::from_custom_dir(&TEMPLATES_DIR)
+    }
+
+    pub fn from_custom_dir<P: AsRef<Path>>(path: &P) -> Result<Self> {
+        if !path.as_ref().exists() {
+            return Err(Error::string(&format!(
+                "missing templates directory: `{}`",
+                path.as_ref().display()
+            )));
+        }
+
+        let template_path = path.as_ref().to_string_lossy().to_string();
+
+        #[cfg(feature = "autoreloader")]
+        let reloader = AutoReloader::new(move |notifier| {
+            let mut environment = Environment::new();
+            let template_path = template_path.clone();
+
+            environment.set_loader(path_loader(&template_path));
+
+            notifier.watch_path(template_path, true);
+            Ok(environment)
+        });
+
+        #[cfg(not(feature = "autoreloader"))]
+        let environment = {
+            let mut environment = Environment::new();
+            environment.set_loader(path_loader(&template_path));
+            environment
+        };
+
+        Ok(Self {
+            #[cfg(debug_assertions)]
+            template_dir: path.as_ref().to_string_lossy().to_string(),
+            #[cfg(feature = "autoreloader")]
+            reloader: std::sync::Arc::new(std::sync::Mutex::new(reloader)),
+            #[cfg(not(feature = "autoreloader"))]
+            environment: std::sync::Arc::new(std::sync::Mutex::new(environment)),
+            phantom: Default::default(),
+        })
+    }
+
+    pub fn render_template<D: serde::Serialize>(
+        &self,
+        key: &str,
+        data: D,
+    ) -> Result<String, Error> {
+        #[cfg(feature = "autoreloader")]
+        let reloader = self.reloader.lock().expect("reloader lock failed");
+        let env = {
+            #[cfg(feature = "autoreloader")]
+            {
+                reloader
+                    .acquire_env()
+                    .or_else(|e| Err(Error::Message(e.to_string())))?
+            }
+            #[cfg(not(feature = "autoreloader"))]
+            self.environment.lock().expect("environment lock failed")
+        };
+
+        let template = env
+            .get_template(key)
+            .or_else(|e| Err(Error::Message(e.to_string())))?;
+        let rendered = template
+            .render(&data)
+            .or_else(|e| Err(Error::Message(e.to_string())))?;
+        Ok(rendered)
+    }
+
+    pub fn render_html<D: serde::Serialize>(
+        &self,
+        key: &str,
+        data: D,
+    ) -> Result<Html<String>, Error> {
+        let result = self.render_template(key, data)?;
+        Ok(Html(result))
+    }
+}
+
+impl ViewRenderer for MinijinjaView<'_> {
+    fn render<S: Serialize>(&self, _key: &str, _data: S) -> Result<String> {
+        self.render_template(_key, _data)
+    }
+}
+
+pub struct MinijinjaViewEngineInitializer;
+
+#[async_trait]
+impl Initializer for MinijinjaViewEngineInitializer {
+    fn name(&self) -> String {
+        "minijinja".to_string()
+    }
+
+    async fn after_routes(&self, router: AxumRouter, _ctx: &AppContext) -> Result<AxumRouter> {
+        let jinja = MinijinjaView::build()?;
+        Ok(router.layer(Extension(ViewEngine::from(jinja))))
+    }
+}